# It is time we see the standings: Do amplifiers have a sonic fingerprint?



## cvjoint

I am aware there are countless threads about this debate as I've been painstakingly involved in many. This thread is not about debating it further per se unless you feel the need to (I'm sure many will choose so and that's fine). I'm mainly interested about the general consensus and belief of the diyma folks.

A few notes: 

I hope these three categories cover everything there is to be covered. If I'm missing anything please do let me know.

The second category: "All amps. sound the same IF they measure the same..." is imo. identical to "All amps. sound different as a result of the built in filters,eq/boost,differences in gain structure etc." and therefore was not included.

Perceived differences in amp. class would go under option 3.


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## ca90ss

NM


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## sqkev

Anyone with any knowledge or experiences with amps should know that all amps should sound differently from one another. I personally don't know of any amps that claim to have no distortions whatsoever or have no variances in frequency response. 

Personally, I prefer certain types of speakers on tubes, certain speakers on solid states. There is NOTHING wrong with some distortions. Distortions = sound signature.


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## FoxPro5

Nevermind


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## CMR22

Ahhh...come on. Say it


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## cvjoint

lol I see a bunch of folks holding off on debating. It's totally allright I emphasized the purpose of the thread to be the poll in order to save my butt from starting "yet another shameless amp. differences" thread.


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## 3.5max6spd

All op amps/input stages are not created equal and very few amplifiers can completely bypass/isolate them from the original signal.


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## Dangerranger

sqkev said:


> Anyone with any knowledge or experiences with amps should know that all amps should sound differently from one another. I personally don't know of any amps that claim to have no distortions whatsoever or have no variances in frequency response. .


True, but the entire debate isn't that we can't confirm that amplifiers measure quite differently and have different characteristics. When taking our knowledge of acoustics into account, the debate stems from the realization of the limitations of the human ear, and that nearly any modern amplifier (within it's limits, of course) is such a small part of the distortion "chain" that it is a very small factor in respect to the distortion of the entire system, and thus is considered to be a non-factor.

If there were a blatantly obvious difference in amplifiers, then there would be no questioning of this. After all, we A/B speakers and hear drastic differences when making a decision.


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## FoxPro5

Is sonic signature quantifiable?

If sound quality is absolute, then the answer is clearly "C." But is sound quality absolute or relative?


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## Hillbilly SQ

i picked "c" only because i've heard differences between my memphis and crossfire amps. i've had multitudes of experience with several different memphis and crossfire amps and the memphis amps just sounded warmer and more laid back to me. the crossfires seemed to be more sterile sounding and such. they almost sounded artificial. comparison was made with onboard crossovers off and actively crossed with my headunit. 

disclaimer: my comments could easily be disproven if someone really wanted to put their mind to it. my comments are just annicdotes and there are too many variables for my comments to be taken with any seriousness at all. my guess is the memphis amps have a touch of distortion in them causing the warmth to be introduced.


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## sqkev

Dangerranger said:


> True, but the entire debate isn't that we can't confirm that amplifiers measure quite differently and have different characteristics. When taking our knowledge of acoustics into account, the debate stems from the realization of the limitations of the human ear, and that nearly any modern amplifier (within it's limits, of course) is such a small part of the distortion "chain" that it is a very small factor in respect to the distortion of the entire system, and thus is considered to be a non-factor.
> 
> If there were a blatantly obvious difference in amplifiers, then there would be no questioning of this. After all, we A/B speakers and hear drastic differences when making a decision.



When you state nearly all modern amplifiers, which amps are you referring to? a krell amp and a passlab amp? a flea market car amp and a t-amp? All are modern amps.
Let's forget about amp topologies here and compare one amp versus another, isn't this topic about amplifier signature?

I have a tube amp (el84) with only a few watts of output (maybe 2-3 per channel), when hooked up to a pair of fullrangers, it sounds entirely diffferently from the onkyo m501 that I have. They were both compared at relatively the same sound level, same room, same placements. If you were to ask me if they had different sound signatures, I'll definitely say yes.


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## NaamanF

I have been spending a lot of my time (and money) playing with headphones and building headphone amps. I definitely believe amps sound different. Even the same amp with different opamps or tubes.


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## jperryss

Is option A a trick to get people that don't read option B?


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## ArcL100

Tonality, soundstage differences, detail differences, pink elephants? Gone through about a dozen amps - sounded same every time.

Noise floor differences? Absolutely!!!

-aaron


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## thehatedguy

Pretty cool once you get something efficient or in super nearfield or both as to what things you can start to hear.



NaamanF said:


> I have been spending a lot of my time (and money) playing with headphones and building headphone amps. I definitely believe amps sound different. Even the same amp with different opamps or tubes.


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## MarkZ

sqkev said:


> Anyone with any knowledge or experiences with amps should know that all amps should sound differently from one another. I personally don't know of any amps that claim to have no distortions whatsoever or have no variances in frequency response.


It's not whether or not they have NONE. It's whether the distortion and FR differences are low enough not to be distinguished by humans.


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## eqsandleds

I will put this out there.

Even if they do, how many of you have the ears to tell the difference?

This may or may not be a good example. This is a DJ example. 

It took me quite awhile, about a year or so to tell which record was out of time while trying to mix. You are listening to the record that is playing out on the monitors and the other inside one side of the cans. At first it very confusing as to which track is to fast. Just ask Teisto, LOL. It takes trained ears to figure this out.

A couple of you here know that I mix. I told you that I am super critical of my mixes and don't like putting them out there. All of my friends have heard my mixes and whenever they can hit record, yes I have parties at my house, and they take the CD with them. Well, I know that I dropped a mix or two durring the set and I can tell on playback, but they can't. They simply do not have the trained ear.

Honestly now, how many of you are influenced by what equipment a group of other people say sounds good?

I went from JL slash amps to Arc XXKs. They sound better to me, but it could be the extra 100% head room that I have.


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## solacedagony

I would take a guess and say that an amplifier playing inside its limits would be limited to sounding different based on any audible distortion and in what way its FR modifies what the speaker receives. I voted B because I'm sure SOME amps are truly "fingerprint-less"; that is, they give the same signal as they received, within human range of audibility. Other amps, which don't give out the same signal that was inputted have this "fingerprint" or modification of signal.

That could be way off, that's just how I've come to understand the situation.


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## Dangerranger

sqkev said:


> When you state nearly all modern amplifiers, which amps are you referring to? a krell amp and a passlab amp? a flea market car amp and a t-amp? All are modern amps.
> Let's forget about amp topologies here and compare one amp versus another, isn't this topic about amplifier signature?
> 
> I have a tube amp (el84) with only a few watts of output (maybe 2-3 per channel), when hooked up to a pair of fullrangers, it sounds entirely diffferently from the onkyo m501 that I have. They were both compared at relatively the same sound level, same room, same placements. If you were to ask me if they had different sound signatures, I'll definitely say yes.



The only amplifiers I can really think of that sway from that would be the few tube designs out there that are intentionally designed with huge distortion. Basically those that design an amplifier nearing 10% THD and are relying on the "tube warmth" marketing chutzpah to sell product. And there really is no solid state counterpart to compare with that, nor is there a solid state counterpart for an 8W SET amp. Modern technology allows us to achieve performance that wouldn't break the audible threshold of human hearing even at a flea market price point, but of course that doesn't mean a manufacturer "has" to do that. It's possible to design an amplifier that's very audibly different, it would mean huge THD and it would sound like complete garbage, but it would be easy to accomplish. Just not very logical from a business standpoint. And it wouldn't be the type of quality equipment that audiophiles are crooning at and getting into heated arguments over, either


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## 89grand

Great thread. I don't recall this ever being discussed before.


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## sqkev

MarkZ said:


> It's not whether or not they have NONE. It's whether the distortion and FR differences are low enough not to be distinguished by humans.


Mark, I believe some amp designers intentionally use certain voicings to their designs/amps. I wouldn't go to say I understand amp topologies/designs to make any claims in certain designs, but I know what I hear (considered that I understand the variables involved in the listening sessions). 

Note that I'm not limiting this discussion to just car audio amps. I feel that the majority of car audio amps are not designed for the trained ears, it's a race for power in car audio, so there's no point in discussing different sounds in this 12volt field.


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## low

yes amps do sound different. as some sites stress, buy the most expensive amp and youre amongst the elite of the elite...kekek


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## npdang

89grand said:


> Great thread. I don't recall this ever being discussed before.


Only about a bazillion times


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## Sephiroth619

Who's the idiot that voted A: All amps sounding the same? 

Oh wait, that was me.


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## MarkZ

sephiroth619 said:


> Who's the idiot that voted A: All amps sounding the same?


I was actually considering it.  But since I don't have experience with every amp ever designed for car audio, I'm not really confident in using terms like "every" and "always". But as a practical matter, yeah, I'd say that virtually all car amps will sound the same when operating within their intended limits.

I may be an idiot, but I'd like to think I know a little bit about amp design. Not as much as some, but enough to at least have a decent understanding about what obstacles need to be addressed, and how to go about doing it. Does everybody who's weighed in on this thread have an understanding about amplifier operation? And does everybody know what variables to control for when designing a listening test, and why failing to do so pretty much makes the anecdotal evidence worthless? It's psychology 101, folks.


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## dodgerblue

i admit the my sonic sig vote - not an easy thing to admit with the watt is a watt majority here ,the differences i seem to notice nomatter the wattage is the soundstage being a BIT wider ,deeper and higher and hi-end response being a BIT crisper but i listen for that stuff ,mid to lowend is typically dependant on power and dont notice much difference , i have taken amps back based on sound alone -crossfire bmf75.4 ,ppi pc 4400 and an older kicker amp zed duece - they just didnt please me like the older amps i was trying to replace at the time - harman tc400q - adcom 4400 ironically rated 40wpch etc . ive owned 35-40 amps in the past and most of the best i found were not newer ,the most powerful , had many features or the most expensive .but naturally its much more feasable to use other means to tailor , alright im ready for the grilling !!


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## forty5cal1911

Did someone mention something about a dead horse?


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## cvjoint

Yeah...I don't think this would have worked with more categories...clearly there are a million ways to interpret every possible scenario. Second and third choices are the heart of the debate. First category I inteded to use as a catchall variable for people that don't particularly care much for amps. or the debates in general. I see not a lot took the bait he he  

I was a bit shocked to see the ratings go from 75% option B to a lead switch over in favor of option C. The way I remember the debates "a watt is a watt" guys generally have more popular support.

This is better than the presidential elections...outcome is undergoing constant change!


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## MarkZ

I'm also very surprised that (C) has gotten so many votes. I can understand the crowd that says various amplifiers sound different, but do these people truly believe that the difference cannot be measured? That it's not a difference in output voltage from the amp, but rather some other force that is foreign to the realm of physics? I don't know if that's what you meant with option C. But when you say "all amps that measure the same sound the same" in option B, then it implies that option C means that amps that measure the same could sound different. Is that what the option C voters really think??


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## Abmolech

Santa Claus is alive and well in the north pole.


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## cvjoint

Or... do all option B voters really believe that by turning off xover and bass boost with the assumption that most modern amplifiers have very low distortion and a relatively flat FR any two amps will sound the same? 

I think there is a general feel for what it takes to believe in B or in C but the line itself is both vague and ambiguous. Imo it is impossible to create distinct cateogries that are clearly defined and not more than 10 (forum limit). Let's think of this the American way: interpret as you whish but make it a two-party system. The posts so far have been awsome and I think underline a lot of nuances that I could not properly portray in the poll.


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## cvjoint

Abmolech said:


> Santa Claus is alive and well in the north pole.


Newton's apple continues to fall down.


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## Abmolech

And we still put the same tired hacks in positions, where they can do most harm. (IE we never learn)

"The first causality of war is truth."


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## cvjoint

Bastard! 

I understand you will give us a hint of relativity...a shade of string theory perhaps?

String theory as applied to acoustics...that's a trip


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## Abmolech

I have never encountered anyone persuaded by facts, unless they had no set opinion.


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## fredridge

How about a third option.

I don't know because I don't have enough experience.

Even with that experience I am not sure I would be willing to sign one of those with all the absolutes given in the statements.


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## FoxPro5

B-Squad said:


> Is sonic signature quantifiable?


Anyone?? I'm being totally serious.


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## solacedagony

B-Squad said:


> Is sonic signature quantifiable?


Can we measure FR, distortion, voltage drops, etc? These, and I'm sure 100 other things which MarkZ or Chad would list, are going to give you your sonic signature. Anything that changes the original signal.


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## fredridge

I was going to expand my previous post, but was thinking something similar.
Any amp by it's nature will effect the signal. That is it's purpose. At the very least it provides gain, but beyond that I would think that any component that the signal travels through would also have an effect on that signal. 

the question is what effect does it have and is it quantifiable as you ask. 
And not only is it sonically(?) detectable (measurable), but can we detect it.

I also understand that there are things we can detect, but really have no ability to identify.
An example, I am not a musician, but my wife is. Whenever we are listening to live music we both have different impressions. I can tell her about mix, staging and what I will call Mechanical stuff and identify how to fix them, she can tell something is wrong but doesn't always know exactly what. With the artistic part or music. I can tell something is wrong, someone messed up and it just doesn't sound right. I can't identify specifics or tell you how to fix, but she can. 

I know that is a very simple example, but it also makes me questions are there differences that we can "hear" but not really understand why or what.

Anyway, most of this is so way beyond my current skill level or understanding, but it does make me think and help me grow in understanding and sometimes it just confuses me more 




B-Squad said:


> Anyone?? I'm being totally serious.


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## durwood

Abmolech said:


> Santa Claus is alive and well in the north pole.





cvjoint said:


> Newton's apple continues to fall down.


Elvis is living on an Island. 

Who here believes there is a way for YOU the everyday user to take an amp out of the box and completely disable or defeat everything that affects how it sounds?

Also, who hear believes they NEVER clip their amp? (If anyone chimes in and says they use a multimeter and testones you will shot and buried in the desert). Just wondering. Maybe I should start another poll


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## Oliver

Do you feel that all amps should have "xtras", [ie. x-overs, bass boost,leds, etc..,], in order for you to get what you're paying for?


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## 3.5max6spd

Some of you dont grasp that even though you may disengage a xover switch or use a full range signal (not using the xover) that the signal still does not completly bypass the pre amp section in most amplifiers and it still suffers coloration.


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## chad

12 hours old, 5 pages long.... This may trump the cap thread or the 25 to life thread.

Ima gonna put my feet up and grab some popcorn.... till wona you's be's yaself and mention's dampaling factor


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## Genxx

Damn. After reading this thread boy am I glad that I never get this worried about the amps I run. Should I? NO I would go crazy trying to find the right sonic signature all the time, if it even exist.

Looks, footprint, good quality, power and cost. Nope nothing in there about me worrying about the sonic footprint of them thank God.

It would be cool though if someone could prove all the theories. Don't think that is going to happen.

Alteast I still continue to learn something everytime I read these threads. Learn young jedi there is so much information in these threads.


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## solacedagony

Genxx said:


> Damn. After reading this thread boy am I glad that I never get this worried about the amps I run. Should I? NO I would go crazy trying to find the right sonic signature all the time, if it even exist.


I don't think there's much reason to worry about it with the amount of processing that most of us have. We can make our amps sound like anything we want.


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## Oliver

There has to be a reason different topologies are used and why some people are willing to pay more for there amps...


. 2 internal DSP 24-bit/96kHz 180 mips.
. Burr-Brown op-amps
. Triple Darlington Toshiba 5000 output stage
. Crystal 24-bit/96kHz converters
. Coaxial and optical inputs
. Digital graphic eq 30 band 1/3 octave
. External digital control from a PC with USB port


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## Genxx

solacedagony said:


> I don't think there's much reason to worry about it with the amount of processing that most of us have. We can make our amps sound like anything we want.


See I just learned something. This is very true. By the time it goes through all the damn proccessing, eqing for active then to the amp we get a mixed bag. Is anyone not running processing at all prior to the amp. So even if there was some sort of sonic singnature is it not negated before we ever get to the amp. Sonic signature mix of all the processing mabey. We would have to take all the other stuff into consideration I guess. OOps did we just through in some variables. 

Ok now I am going way off topic. Let me get out of this thread before I get in over my head.LOL Sorry Guys.


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## MarkZ

3.5max6spd said:


> Some of you dont grasp that even though you may disengage a xover switch or use a full range signal (not using the xover) that the signal still does not completly bypass the pre amp section in most amplifiers and it still suffers coloration.


The preamp stage (ie. signal processing and level adjustment) usually has very little bearing on the signal. Op amps are god's creation.


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## MarkZ

Genxx said:


> It would be cool though if someone could prove all the theories. Don't think that is going to happen.


It's been done.


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## durwood

MarkZ said:


> The preamp stage (ie. signal processing and level adjustment) usually has very little bearing on the signal. Op amps are god's creation.



Why do they make different ones and why do people find the need to replace opamps in all sorts of things such as headphone amps,dacs, soundcards and amps then?   

The LM4562 is supposed to be an opamp that trumps some of the burr brown ones now like the OPA2107.

Dammit why do I always get sucked into these debates.


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## dbphelps

solacedagony said:


> I don't think there's much reason to worry about it with the amount of processing that most of us have. We can make our amps sound like anything we want.


Very, very true, and a point I don't think a lot realize... As long as the amplifier does not 'give up' when pushed hard, there should be no complaints with all the adjustability in most of todays processing that we have on hand...

Now I am putting together another system as a 'true SQ' based one... Basically, a Alpine CDA-7949 headunit (argueably one of THE best transports/cd units ever made, pre-F#1 and on-par with the F#1 stuff), PXA-H600 processor (again pre-F#1, and designed solely around cleanliness and accurracy of the signal, with even the automatic processing of the bass region designed for complete tonal balance in an automotive environment, which I feel most people just didn't understand/appreciate, as well as VERY high quality Burr-Brown DAC stages), and out to a set of the newer Zed Audio amplifiers (with the Burr-Brown op-amp upgrades)... Per my 'tastes' I feel most of my bets are hedged against the highest quality overall system from the input signal to the amps with still some tuning 'ability' to be afforded within the PXA-H600s parametric EQs, time correction and auto-corrections... It is just a matter of finding the proper speakers to compliment it along with the proper installation to make the most of the equipment...

Back to the topic on hand, I seriously believe that the input stages have the biggest effect on the sonic 'signature' outside of total power output. I also believe that certain amp designs do not lend themselves to completely linear output when pushed towards clipping, ie the more power they put out the 'worse' they sound due to design and build issues...

I firmly believe that amplifiers can and do sound 'similiar' at various power output levels, but I do also stand that towards the upper end of thier output capabilities is where inferior designs/builds start showing thier weaknesses and where 'overbuilt' amplifiers start to stand-out and really 'shine'... Personally that is my fixation with the Zed Audio amps of various name-brands, including thier own, as I have owned quite a few of them (ESX, Hifonics, Nakamichi, USAcoustics, Zed) and have found thier 'higher end' amps to have much better 'headroom' when it comes to overall sound quality when pushed hard...

Now that is not to say that I have only owned Zed amps, as I have owned amps made by Alpine, USAcoustics (non-Zed made), Proton, Rockford, Inifinity and Orion, and one of the biggest differences noticed is the more expensive amplifiers 'usually' had more power than rated, or put out at least thier rated power when pushed to the limit... Some of the best of the non-Zed are the Protons (which I still have in my conversion van, with them being 18 years old at this point), which in regards to 'cleanliness of design' by looking at the circuit board is definintly late 80's era in regards to layout and connections (lots of excess wiring used to connect things internally, etc), but still built like a tank and all 4 of those amps are going strong still, with a 'sound quality' that I would put above most amps produced now-a-days with the same power ratings they have... That is not to say they do not put out more than rated power, but for certain they put out at least thier rating... A lot may have to do with thier input stages, or just the overall design...


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## kevin k.

Abmolech said:


> And we still put the same tired hacks in positions, where they can do most harm. (IE we never learn)
> 
> "The first causality of war is truth."


'Causality' or 'casualty'...?

Or, maybe both...?


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## backwoods

I've heard lots of differences in amps, and I have my favorites. I have had installs that required no processing and have sounded phenominal. 

Reasoning is choosing amps with great built in crossovers...etc..

But, there is 10k supporting option B, and until they find a new specification that isn't currently tested, I have to stick to it. 

I may believe amps sound different, but I can't argue with science. If they measure the same, whether it is a head unit, processor, amp, then it's got to sound the same.

Now, what if this was speakers...

Do all speakers that measure the same, sound the same?


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## MarkZ

durwood said:


> Why do they make different ones and why do people find the need to replace opamps in all sorts of things such as headphone amps,dacs, soundcards and amps then?
> 
> The LM4562 is supposed to be an opamp that trumps some of the burr brown ones now like the OPA2107.
> 
> Dammit why do I always get sucked into these debates.


I have no idea why people bother replacing .02% THD+N devices.


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## chad

MarkZ said:


> I have no idea why people bother replacing .02% THD+N devices.


I have replaced the line drive Op-Amps in my mixing console and anything that could be sending down a snake for that matter. I noticed a huge improvement in driving long lines by using BB devices over the old trusty RC4558. Short lines, like less than 50' no difference. Long lines like 200+ Feet, big difference, especially in signal stability, etc.

In a car or home audio situation within a chassis I see not much improvement. keep in mind the old TLO series is FET based and some designs that call for that device actually require it for some-odd reason I haven't bothered to figure out yet


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## MarkZ

chad said:


> I have replaced the line drive Op-Amps in my mixing console and anything that could be sending down a snake for that matter. I noticed a huge improvement in driving long lines by using BB devices over the old trusty RC4558. Short lines, like less than 50' no difference. Long lines like 200+ Feet, big difference, especially in signal stability, etc.


Why's that? Output impedance?


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## chad

MarkZ said:


> Why's that? Output impedance?


I would imagine it has to do with the circuit design of the servo and it's ability to deal with long cable runs. So yeah, probably output impedance for the easy call.

Improvements came in the way of HF clarity and big ballsy low end. I imagine 250' of quad cable can add a bit of capacatance to the line possibly angering the original design. I replaced them after having oscillation issues. that particular situation had to drive over 600 feet to a fireworks launching area. I sent the cues to them.

I'm having a forgetful moment as to the exact model number but I can say that these op amps WILL drive a speaker


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## durwood

MarkZ said:


> I have no idea why people bother replacing .02% THD+N devices.


It's actually less than that IIRC--maybe aroudn even 0.00002%. I'd have to look at the data sheets, but there are all sorts of specs on those parts that vary. I'm just saying that if you want to look at all the nity grity stuff, I guess you have to look at component level on why an amps sounds different. If you want to get real crazy, you look at the internals of the op amp, transistor, caps itself. That's complete overkill, but there are reasons people select different component parts no? That's all I am trying to get at. Could you tell a difference? I have no idea. I haven't really tried. Could I tell you what is causing any differences, probably not.


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## Oliver

dbphelps said:


> Very, very true, and a point I don't think a lot realize... As long as the amplifier does not 'give up' when pushed hard, there should be no complaints with all the adjustability in most of todays processing that we have on hand...
> 
> Now I am putting together another system as a 'true SQ' based one... Basically, a Alpine CDA-7949 headunit (argueably one of THE best transports/cd units ever made, pre-F#1 and on-par with the F#1 stuff), PXA-H600 processor (again pre-F#1, and designed solely around cleanliness and accurracy of the signal, with even the automatic processing of the bass region designed for complete tonal balance in an automotive environment, which I feel most people just didn't understand/appreciate, as well as VERY high quality Burr-Brown DAC stages), and out to a set of the newer Zed Audio amplifiers (with the Burr-Brown op-amp upgrades)... Per my 'tastes' I feel most of my bets are hedged against the highest quality overall system from the input signal to the amps with still some tuning 'ability' to be afforded within the PXA-H600s parametric EQs, time correction and auto-corrections... It is just a matter of finding the proper speakers to compliment it along with the proper installation to make the most of the equipment...
> 
> Back to the topic on hand, I seriously believe that the input stages have the biggest effect on the sonic 'signature' outside of total power output. I also believe that certain amp designs do not lend themselves to completely linear output when pushed towards clipping, ie the more power they put out the 'worse' they sound due to design and build issues...
> 
> I firmly believe that amplifiers can and do sound 'similiar' at various power output levels, but I do also stand that towards the upper end of thier output capabilities is where inferior designs/builds start showing thier weaknesses and where 'overbuilt' amplifiers start to stand-out and really 'shine'... Personally that is my fixation with the Zed Audio amps of various name-brands, including thier own, as I have owned quite a few of them (ESX, Hifonics, Nakamichi, USAcoustics, Zed) and have found thier 'higher end' amps to have much better 'headroom' when it comes to overall sound quality when pushed hard...
> 
> Now that is not to say that I have only owned Zed amps, as I have owned amps made by Alpine, USAcoustics (non-Zed made), Proton, Rockford, Inifinity and Orion, and one of the biggest differences noticed is the more expensive amplifiers 'usually' had more power than rated, or put out at least thier rated power when pushed to the limit... Some of the best of the non-Zed are the Protons (which I still have in my conversion van, with them being 18 years old at this point), which in regards to 'cleanliness of design' by looking at the circuit board is definintly late 80's era in regards to layout and connections (lots of excess wiring used to connect things internally, etc), but still built like a tank and all 4 of those amps are going strong still, with a 'sound quality' that I would put above most amps produced now-a-days with the same power ratings they have... That is not to say they do not put out more than rated power, but for certain they put out at least thier rating... A lot may have to do with thier input stages, or just the overall design...


Well said!!!


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## DS-21

My fundamental problem with this poll is my fundamental problem with a lot of what counts as discourse in America today: the assumption that a question with roots in empirical truth can be answered by inserting an overlay of democracy atop it. It is the worst of postmodernism run amok. The way to answer this question, or for that matter many of the questions in our nation is not to just ask people, but to control the variables and perform experiments.

In the case of "amp sound," said experiments have been done long ago, and replicated many times since in different settings, with the same answer. The jury is indisputably in. True, there people with vested interests in suppressing reality, and there are people who are gullible and/or ignorant and/or stupid. Kind of like those three Republican presidental wannabes who raised their hand to the question "who doesn't believe in evolution?" a little while ago. But the fact that nearly half of the people who voted on this thread fall into one of those latter four categories says _absolutely nothing_ about the underlying truth.

Otherwise, one might as well say that Santa Claus and the Tooth Fairy and unicorns should be thought of as real because x% of people believe they are.


----------



## backwoods

DS, 

If it wasn't for people disagreeing, there would be nothing to push the testing/experiments.

The more POV's that are available, the more testing that is required, and the more concrete a theory can become. 

Besides, you never know, there may still be variables that we haven't quantified yet.


----------



## Guest

DS-21 said:


> My fundamental problem with this poll is my fundamental problem with a lot of what counts as discourse in America today: the assumption that a question with roots in empirical truth can be answered by inserting an overlay of democracy atop it. It is the worst of postmodernism run amok. The way to answer this question, or for that matter many of the questions in our nation is not to just ask people, but to control the variables and perform experiments.
> 
> In the case of "amp sound," said experiments have been done long ago, and replicated many times since in different settings, with the same answer. The jury is indisputably in. True, there people with vested interests in suppressing reality, and there are people who are gullible and/or ignorant and/or stupid. Kind of like those three Republican presidental wannabes who raised their hand to the question "who doesn't believe in evolution?" a little while ago. But the fact that nearly half of the people who voted on this thread fall into one of those latter four categories says _absolutely nothing_ about the underlying truth.
> 
> Otherwise, one might as well say that Santa Claus and the Tooth Fairy and unicorns should be thought of as real because x% of people believe they are.


agreed completely ... with _everything_ in this post.

The topic at hand is _not_ a matter of "belief", or popular opinion. Science has already answered the question definitively.


----------



## MarkZ

durwood said:


> It's actually less than that IIRC--maybe aroudn even 0.00002%. I'd have to look at the data sheets, but there are all sorts of specs on those parts that vary.


Oh, I know. It's a lot lower than a "typical" audio op amp. That's what I meant -- replacing a .02% THD one with one that's a lot lower. That's a very small amount of distortion to begin with.



> I'm just saying that if you want to look at all the nity grity stuff, I guess you have to look at component level on why an amps sounds different. If you want to get real crazy, you look at the internals of the op amp, transistor, caps itself. That's complete overkill, but there are reasons people select different component parts no? That's all I am trying to get at. Could you tell a difference? I have no idea. I haven't really tried. Could I tell you what is causing any differences, probably not.


Gotta be careful though when you're looking at individual component specs. It can actually be misleading because of all the local and global feedback going on in various parts of the amplifier. A well-designed amplifier actually tries to minimize the quality and tolerances (and even values, within reason) of most of the components. The distortion and noise performance of an amplifier is dominated by design and layout, not part "quality". Now, a good design may call for more parts (more parts = more money). But you get a better idea about that by looking at the schematic and the layout than you do by examining the spec sheet of each transistor and the tolerance of each resistor. 

IMO, the biggest reason THD values for car amplifiers tend to be on the order of tenths or hundredths of a percent instead of much lower is because of poor thermal bias tracking strategies and oversimplistic input stages. That actually has nothing to do with what kind of transistors they use, how well they match betas, etc.

[PS - when I say "input stage" a couple lines up, I'm referring to the input stage of the actual amplification section, not the gain/signal processing part.]


----------



## cvjoint

I beg to differ, this poll was not put forth to sway anybody's outlook. It is simply what it is...a poll, I have not power to change the outcome nor did I know how the tally would show. I think you guys read to much into it...I saw it as an opportunity to count the oppinions of those who choose not to debate in these sort of threads.

Personally I don't think it's murder to go against what it is contemporary science fact. It is perfectly ok to not believe in evolution, it is perfectly ok to believe in amp fingerprint, it is ok to think miracles that defy the laws of physics can happen. One can appreciate the scientific approach without fully employing it in every instance. It that's what makes one a believer and at odds with present science than so be it.

Then there is those little shortcomings of proven theories that fall in time. Newton's laws don't hold 100% of the time and neither do the RC challenge findings.


----------



## MarkZ

backwoods said:


> DS,
> 
> If it wasn't for people disagreeing, there would be nothing to push the testing/experiments.
> 
> The more POV's that are available, the more testing that is required, and the more concrete a theory can become.
> 
> Besides, you never know, there may still be variables that we haven't quantified yet.


What kind of variables? We can fully characterize signals and their properties (thanks to Fourier). The only contention that really remains is whether or not our testing brings out the distortion that music does. Well, that's been tested too. The hafler "straight wire" tests seemed to account for that. The basic idea is this: drive a comparator circuit with the raw signal and an amplified version of the signal (using the amp of your choosing), and then see if there's an output. If not, then the two signals are equivalent. There's no unchartered territory when it comes to voltage.


----------



## MarkZ

cvjoint said:


> I beg to differ, this poll was not put forth to sway anybody's outlook. It is simply what it is...a poll, I have not power to change the outcome nor did I know how the tally would show. I think you guys read to much into it...I saw it as an opportunity to count the oppinions of those who choose not to debate in these sort of threads.
> 
> Personally I don't think it's murder to go against what it is contemporary science fact. It is perfectly ok to not believe in evolution, it is perfectly ok to believe in amp fingerprint, it is ok to think miracles that defy the laws of physics can happen. One can appreciate the scientific approach without fully employing it in every instance. It that's what makes one a believer and at odds with present science than so be it.
> 
> Then there is those little shortcomings of proven theories that fall in time. Newton's laws don't hold 100% of the time and neither do the RC challenge findings.


But it seems you're confusing "science" with what we understand about physics. "Science" is not a discipline that you study to understand how the physical world works. It's a _tool_ that you use to logically arrive at conclusions. If Newton's laws are incomplete, it's not the "science" that's at fault. It's our understanding of the physical world.

If you believe that what we currently know about electricity is incomplete, that's fine. But don't cast aside the scientific method. Only through science and logic do you have a chance to arrive at valid conclusions.


----------



## rcurley55

werewolf said:


> agreed completely ... with _everything_ in this post.
> 
> The topic at hand is _not_ a matter of "belief", or popular opinion. Science has already answered the question definitively.


while I agree - remember, your ears are connected to your brain - which is also connected to your eyes


----------



## Guest

cvjoint said:


> I beg to differ, this poll was not put forth to sway anybody's outlook. It is simply what it is...a poll, I have not power to change the outcome nor did I know how the tally would show. I think you guys read to much into it...I saw it as an opportunity to count the oppinions of those who choose not to debate in these sort of threads.
> 
> Personally I don't think it's murder to go against what it is contemporary science fact. It is perfectly ok to not believe in evolution, it is perfectly ok to believe in amp fingerprint, it is ok to think miracles that defy the laws of physics can happen. One can appreciate the scientific approach without fully employing it in every instance. It that's what makes one a believer and at odds with present science than so be it.
> 
> Then there is those little shortcomings of proven theories that fall in time. Newton's laws don't hold 100% of the time and neither do the RC challenge findings.


bad analogies.

It is not, in my view, perfectly OK to "not believe" in evolution. First, evolution is NOT a belief system, it is a well-proven scientific model. Second, casting it as such causes crazy things to happen, like ignorant school boards preventing evolution from being taught in school.

Yes, Newtons' Laws were found to be inaccurate in extreme circumstances. But please ... let's not suggest that the two remaining mysteries of science are :

1. A unfiied theory of forces, that unites electromagnetism, gravity, strong and weak nuclear.

2. A adequate description of an audio power amplifier, providing simple electrical gain to a 20kHz signal.


----------



## Guest

MarkZ said:


> But it seems you're confusing "science" with what we understand about physics. "Science" is not a discipline that you study to understand how the physical world works. It's a _tool_ that you use to logically arrive at conclusions. If Newton's laws are incomplete, it's not the "science" that's at fault. It's our understanding of the physical world.
> 
> If you believe that what we currently know about electricity is incomplete, that's fine. But don't cast aside the scientific method. Only through science and logic do you have a chance to arrive at valid conclusions.


Mark said it better 

And no matter what, those who don't understand science will _always_ try to equate it to religion.


----------



## durwood

MarkZ said:


> Oh, I know. It's a lot lower than a "typical" audio op amp. That's what I meant -- replacing a .02% THD one with one that's a lot lower. That's a very small amount of distortion to begin with.
> 
> 
> 
> Gotta be careful though when you're looking at individual component specs. It can actually be misleading because of all the local and global feedback going on in various parts of the amplifier. A well-designed amplifier actually tries to minimize the quality and tolerances (and even values, within reason) of most of the components. The distortion and noise performance of an amplifier is dominated by design and layout, not part "quality". Now, a good design may call for more parts (more parts = more money). But you get a better idea about that by looking at the schematic and the layout than you do by examining the spec sheet of each transistor and the tolerance of each resistor.
> 
> IMO, the biggest reason THD values for car amplifiers tend to be on the order of tenths or hundredths of a percent instead of much lower is because of poor thermal bias tracking strategies and oversimplistic input stages. That actually has nothing to do with what kind of transistors they use, how well they match betas, etc.
> 
> [PS - when I say "input stage" a couple lines up, I'm referring to the input stage of the actual amplification section, not the gain/signal processing part.]


I'm with you. The amp design is a whole system, not just an individual part. I wasn't ever disagreeing, but things can happen in poorly desinged feedback systems and opamp circuits. It might look good on paper, but in the lab it might take one little thing and the circuit goes haywire with oscillations. So then you have to tame that by adding in more components. All of that can play a part IF it's in the signal path-good or bad. At least that is what I believe. 

I'm not an amp designer, nor do I clame to be an expert. 
I just remember performing experiments in school that required us to swap out the opamp and not change anything to see what would happen-the experiment was to demostrate oscillations. We then had to TRY to figure out why it happened with one opamp and not the other. It sounds like Chad got a dose of real life experience with that.


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## chad

werewolf said:


> And no matter what, those who don't understand science will _always_ try to equate it to religion.


Now *That's* gotta go in someone's sig file!


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## durwood

Dammit! I just filled mine up with two new ones. Who has dibs?


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## backwoods

MarkZ said:


> What kind of variables?


 
hell if I know... If I knew, I'd name it after myself...What I was mentioning is one day, something else may be found. 


The beauty of science is, the broad scope of applications a single experiment could affect. 

It's just finding that variable, and figuring out where to apply it.


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## cvjoint

MarkZ said:


> If you believe that what we currently know about electricity is incomplete, that's fine. But don't cast aside the scientific method. Only through science and logic do you have a chance to arrive at valid conclusions.


I agree, I am all for the scientific method. I just whished people would be more open to alternate findings (be it proven scientifically or not) rather than to swear their life on one particular finding. I stumble upon subtle personal attacks whenever these threads pop up and I think some folks should be more considerate of others.


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## FoxPro5

MarkZ said:


> But it seems you're confusing "science" with what we understand about physics. "Science" is not a discipline that you study to understand how the physical world works. It's a _tool_ that you use to logically arrive at conclusions. If Newton's laws are incomplete, it's not the "science" that's at fault. It's our understanding of the physical world.
> 
> If you believe that what we currently know about electricity is incomplete, that's fine. But don't cast aside the scientific method. Only through science and logic do you have a chance to arrive at valid conclusions.


That's a good thing to remember for shizzle, Mark Zizzle! 

As Werewolf said, people often get science and religion mixed up. Science can tell you _how_ by making a serious of better guesses over time, but only self-discovery (religion) can tell you _why_! 

In the event that you cannot find an answer through the "limitations" of science, then you need to meditate. Faith begins were knowledge ends.


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## chad

So if I design a rig with great scientific detail and then pray like hell it does not blow up..... is that science or religion?


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## Guest

chad said:


> So if I design a rig with great scientific detail and then pray like hell it does not blow up..... is that science or religion?


it's ... IT'S ... SCIENTOLOGY !!!!  

disclaimer : no offense intended


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## Thumper26

k, so i didn't read all 8 pages and this may have been said, but i picked c just b/c of the hardware that amps are made with. a capacitor's value is within a certain tolerance. that there is enough to have a unique signature even from amp to amp of the same model. granted, we may not be able to hear it, but the core differences on the board are enough to create different signatures on the amps.

that's my take on it anyways. also, i think it depends on the speakers you're using to listen for the differences. you prolly won't hear a difference using a couple of road gear speakers from walmart, whereas you might from a set of Seas.


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## chad

werewolf said:


> it's ... IT'S ... SCIENTOLOGY !!!!


Awesome!


----------



## FoxPro5

chad said:


> So if I design a rig with great scientific detail and then pray like hell it does not blow up..... is that science or religion?


It's life. 

You guys that love your sonic signatures (not saying it's bad if you do!!) will appreciate the Listener Comments at the end of this. I thought it was hilarious.  

Do All Amplifiers Sound The Same? by David L Clark


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## DS-21

chad said:


> So if I design a rig with great scientific detail and then pray like hell it does not blow up..... is that science or religion?


Engineering.


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## fredridge

am I missing something in this thread, looks like it keeps bumping, but can't see anything new


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## 3.5max6spd

fredridge said:


> am I missing something in this thread, looks like it keeps bumping, but can't see anything new


the poll?


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## chad

3.5max6spd said:


> the poll?


egg-zachary


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## 60ndown

poll is close, i wonder if thats cos no-one knows chit?  


trust your ears.

(just avoid getting into genIsis demo vehicles  )


----------



## Guest

B-Squad said:


> It's life.
> 
> You guys that love your sonic signatures (not saying it's bad if you do!!) will appreciate the Listener Comments at the end of this. I thought it was hilarious.
> 
> Do All Amplifiers Sound The Same? by David L Clark


That's a GREAT article. Even for those who don't understand a test where variables are well controlled, or the statistical analysis of the outcome ... you gotta love the listener's comments at the end 

Inescapable conclusion : when the brain no longer knows the brand name, faith-based hearing acuity goes right out the window. Every time


----------



## sqkev

werewolf said:


> That's a GREAT article. Even for those who don't understand a test where variables are well controlled, or the statistical analysis of the outcome ... you gotta love the listener's comments at the end
> 
> Inescapable conclusion : when the brain no longer knows the brand name, faith-based hearing acuity goes right out the window. Every time


No offense, but I think your inescapable conclusion is flawed.

How? the test was conducted so that the amps are gainmatched and operated under clipping. Plus, the fact that the listeners were listening to the amps back and forth for some period of time. 

and here's my reasoning

-How many here listen to their amps under clipping at all times? Definitely not an average Joe who listen to his music on an everyday basis. I listen to my distorted tube amps all the times, do I keep it under 1-2 watts so it won't distort? No, I prefer some distortions sometimes.

-I don't know about everyone here, but my ears are shot after a few minutes of tuning. How do you use your ears to differentiate one sound after another, back and forth? I believe are ears are not very good tools when it comes to accurately pick out certain sounds after being strained. Our brains were trained to adapt. 

It comes back to the question whether one can pick out amplifier's signatures through our ears. Does any of these testing methods account for the brains? after all, we don't hear with our eyes, and we don't hear with our ears. 

BTW, just to contradict in myself, I'm a strong believer in pro audio amps. Almost any sound can be tailored to your liking if you have good enough dsp. Dsp and power are getting cheaper and I just love taking advantage of that. I wouldn't go out and spend $5000 on an amp, but I'm not the one to say all amps sound the same.


----------



## Archmage

My opinion coincides with those of: werewolf, markZ, np, chad...etc

There are many scenarios in which we can create audible differences which many would attribute to amplifiers - and sometimes it may be the case that the "subjectivists" ARE hearing some shortcoming in the amplifier design - that perhaps it is too easy to reproduce a certain misaligned setup/config - that the amp is just picky.

WHAT are we hearing that is different? Here are some (bad) guesses:

- Impedance: All amps have output impedance. One goal may be to minimize this, but as there is no ideal speaker load (no pure resistance, instead we have reactance varying w/ frequency) = the amp will be influenced. --- CHAD mentioned hearing some difference possibly attributed to this influence (lots of cable).

- Clipping performance: amps may clip with high dynamic range sources. How do they recover from a transient overload? Different amps recover differently!

- Distortion?: several factors = crossover distortion (except class A), slew-induced/intermodulation distortion, phase/fr, open-loop performance? Unfortunately - there isn't much of an audible difference here. Phase distortion in amps may cause some delays, but they are inaudible. I also doubt that an amplifier is going to triangulate the signal as in slew-rate induced distortion - but if it did, it might be audible. 

Open-loop performance and feedback may have something to do with noise-floor, but hell so could white noise (thermal and shot noise, flicker LF noise). More than likely an audible noise-floor may have something to do with a ground-loop of some sort - or some similar config. complication.

** I'm growing weary of this. There is plenty of information available to support the objectivists, but I don't think it can be completely ruled out that the subjectivists ARE hearing some differences (configuration most likely). I'd like to think that there is some difference in designs, however I know that if I were to market some amps, I'd emphasize: efficiency, power, cooling (cuz I LOVE cooling things off).

- How's it going CVjoint?


----------



## Guest

sqkev said:


> No offense, but I think your inescapable conclusion is flawed.
> 
> How? the test was conducted so that the amps are gainmatched and operated under clipping. Plus, the fact that the listeners were listening to the amps back and forth for some period of time.
> 
> and here's my reasoning
> 
> -How many here listen to their amps under clipping at all times? Definitely not an average Joe who listen to his music on an everyday basis. I listen to my distorted tube amps all the times, do I keep it under 1-2 watts so it won't distort? No, I prefer some distortions sometimes.
> 
> -I don't know about everyone here, but my ears are shot after a few minutes of tuning. How do you use your ears to differentiate one sound after another, back and forth? I believe are ears are not very good tools when it comes to accurately pick out certain sounds after being strained. Our brains were trained to adapt.
> 
> It comes back to the question whether one can pick out amplifier's signatures through our ears. Does any of these testing methods account for the brains? after all, we don't hear with our eyes, and we don't hear with our ears.
> 
> BTW, just to contradict in myself, I'm a strong believer in pro audio amps. Almost any sound can be tailored to your liking if you have good enough dsp. Dsp and power are getting cheaper and I just love taking advantage of that. I wouldn't go out and spend $5000 on an amp, but I'm not the one to say all amps sound the same.


the excuses never end  

- amps didn't clip ... surely clipping behavior is why someone would drop 6 grand on an amp, instead of 200 bux! That must be why the megabuck amps have the liquid midrange, velvety top end, etc. It's all in their massive distorting behavior as they clip! 

- listening fatigue, from comparative evaluation  But listening fatigue doesn't ... has _never_ ... impacted the ears/brain of someone who holds a religious belief that amps which measure the same still somehow sound different? How exactly did listener fatigue _not_ impact that religious belief? Was it formed from a few minutes of listening over the years, always followed by a day of rest? In other words ... how can you be sure that it wasn't fatigue that led you to the conclusion that amps sound different?

I'm sorry, not trying to flame any one individual. But ... don't these excuses just start to sound like the desperate last stand, of someone who can't accept scientifically and logically valid results staring them in the face?

And of course ... ALL of these testing procedures include the brain, ears, hearts and any other organs you wish to mention. I don't think anyone shut down their brains during the blind test, but kept them open in the beginning.

Read the paper again ... the comments before the test (when brands are known) compared to during/after, are very telling.

*When the brand is known, the differences are "obvious". Hide the brand, match the gains ... and the differences disappear. Same old story, month after month, year after year ...*


----------



## sqkev

werewolf said:


> the excuses never end
> 
> - amps didn't clip ... surely clipping behavior is why someone would drop 6 grand on an amp, instead of 200 bux! That must be why the megabuck amps have the liquid midrange, velvety top end, etc. It's all in their massive distorting behavior as they clip!
> 
> - listening fatigue, from comparative evaluation  But listening fatigue doesn't ... has _never_ ... impacted the ears/brain of someone who holds a religious belief that amps which measure the same still somehow sound different? How exactly did listener fatigue _not_ impact that religious belief? Was it formed from a few minutes of listening over the years, always followed by a day of rest? In other words ... how can you be sure that it wasn't fatigue that led you to the conclusion that amps sound different?
> 
> I'm sorry, not trying to flame any one individual. But ... don't these excuses just start to sound like the desperate last stand, of someone who can't accept scientifically and logically valid results staring them in the face?
> 
> And of course ... ALL of these testing procedures include the brain, ears, hearts and any other organs you wish to mention. I don't think anyone shut down their brains during the blind test, but kept them open in the beginning.
> 
> Read the paper again ... the comments before the test (when brands are known) compared to during/after, are very telling.
> 
> *When the brand is known, the differences are "obvious". Hide the brand, match the gains ... and the differences disappear. Same old story, month after month, year after year ...*


No desperate excuses here, I'm not one to spend a few thousands buying expensive amps and now having to justify my purchases. 
All I'm saying is that in a regular/typical room, where speaker 1 is being fed with a signal that is amplifed with certain distortions, one could probably hear it different from another amp that he has.



I'm not sure whether anyone can make it out that I'm playing the devil's advocate here, but I'm just presenting the view from a music lover. No, we don't listen to treated rooms (or cars), nor do we know the amp's limits and keep listening under the most optimally condition. In the real life test, there are variables and there are people who are conditioned to distortions and those who prefer distortions (I'm one of those that prefer "good" distortions).


----------



## Guest

i hear you dude.

But ... clipping is universally recognized as a "bad" distortion. It's primarily an odd-order distortion, unlike the more pleasing even-order variety (predominantly second order). So if the excuse (my word, i know, not yours) is that the amps were not allowed to clip ... who could argue that a sonically better result would be achieved by spending a few more bux on an amp that wouldn't clip ... by virtue of more power, something always worth paying for ... rather than a lower power, audiosnob amp that clips in a "magical" way? One is undeniably more _accurate_ than the other, and arguably more _pleasing_ ... given the nature of clipping distortion.

Of course ... clipping behavior and recovery will vary from amp-to-amp.

What exactly are you paying for?


----------



## cvjoint

What's up Archmage? I'm taking a last glance at this for a few days. I shall be flying the next 24 hours or so.

I hope one day I'll be able to do a proper blindfold test where I get to pick the amps I noticed the most sound difference in and isolate all applicable variables with top notch equipment.

Until then I'll let Budha pick my amps


----------



## Diru

yes...


----------



## Guest

cvjoint said:


> Until then I'll let Budha pick my amps


he couldn't be bothered ... of this, i'm quite certain


----------



## sqkev

werewolf said:


> i hear you dude.
> 
> But ... clipping is universally recognized as a "bad" distortion. It's primarily an odd-order distortion, unlike the more pleasing even-order variety (predominantly second order). So if the excuse (my word, i know, not yours) is that the amps were not allowed to clip ... who could argue that a sonically better result would be achieved by spending a few more bux on an amp that wouldn't clip ... by virtue of more power, something always worth paying for ... rather than a lower power, audiosnob amp that clips in a "magical" way? One is undeniably more _accurate_ than the other, and arguably more _pleasing_ ... given the nature of clipping distortion.
> 
> Of course ... clipping behavior and recovery will vary from amp-to-amp.
> 
> What exactly are you paying for?


so you would venture to say that: inherently, the sound tube and transistors are different?


----------



## iyamwutiam

IF the premise is - that there is NO difference between amp A & B - then on a broadly applied test - shouldn't the expected result be -50%. That is you take the entire population of ECA/DIYMobile/IASCA etc -and have them do an A/B test. IF there is no difference between amps then the results SHOULD be 50%. However -David Clarke has shown that there ARE people who are picking out/ perceiving differences. http://www.provide.net/~djcarlst/abx_pwr.htm

That is the confusion with the amp challenge. It is a challenge not a test. To pick 24/24 times correctly in other words putting the onus of 'your' theory on the observer to be correct a stupendous 24/24 times rather than going about it logically.

Logically - NO DIFFERENCE should yeild a score of chance 50% - any consistent deviation would actually point to a difference. How relevant this deviation is is subject to the arbritrary whim - for example - to say a p of .05 (that it could occur only 5% of the time by chance). In addition - there are multiple studies showing observer bias, testing bias, and most of all believe it or not - for people being tested actully because they are being tested altering their choice. To take the converse argument that anything less than a 100 percent THEREFORE equals 50 percent - is specious and most importantly indicates a spurious motivation rather than an open attempt to gain insight.

Although methodologies are modified, variable added - one can not be sure if this is a persistent attempt to PROVE a hypothesis or an objective attempt to gain insight. It is difficult even for the scientist himself - to be aware -despite a multitude of claims to the contrary and of course the enshrinement of the scientific method being "unparalleled". I am not dimishing the scientific method but I am pointing out what has occured recurringly in all scientific endevors -that is the pollution of the 'ideal' by the human. It does occur and in my opinion is becoming more commonplace since the industrialization/commercialization of science.

For example - a great control study along side an amp challenge would be to correlate if the difference in picking between the same amp. Obviously this would also have to be double blinded (both the tested and the tester) can not know.

The point is referring to the amp challenge instead of orgainzing a small organized study (which defintiely I think would be possible) may be an interesting and viable alternative though while not resolving the question may help explore it.


----------



## Archmage

cvjoint said:


> What's up Archmage? I'm taking a last glance at this for a few days. I shall be flying the next 24 hours or so.
> 
> I hope one day I'll be able to do a proper blindfold test where I get to pick the amps I noticed the most sound difference in and isolate all applicable variables with top notch equipment.
> 
> Until then I'll let Budha pick my amps


No worries dude. Your amp setup is great - just keep the headroom and it'll be golden.

On this whole amp issue: Both the engineers and the subjectivist "audiophiles" can be adamant snobs - and that's a good thing. On this forum we realize that there is a good reason to pay more for a decent amp setup, which you have, but no reason to pay ridiculous sums for amps, which you haven't.

I feel as if we're not really arguing about much on here... this discussion isn't going to change our amplifier purchases all that much - I would still prefer an amp that is "technically" better than worse even if it is just a 10% improvement in maybe 1/100th of the attributable distortion above midbass frequency. [hyperbolic argument by exclusion of other variables = joke :blush: ]


Also: Though many could be quite critical of your audio setup, your system would put most others to shame. You should feel quite


----------



## Archmage

uhm... I don't really want to look at it in-depth right now.

BUT: in that ABX testing, I'm fairly certain that if people did perceive differences, there were tube amps or clipping involved. I'd suggest a re-read, but maybe I should read it first eh...heh


----------



## Guest

sqkev said:


> so you would venture to say that: inherently, the sound tube and transistors are different?


inherently? no.

Tube amps can sound very different, for very well understood ... and very measurable ... reasons. These include : higher distortion (even below clipping, especially for low negative feedback designs), higher noise, worse frequency response (not usually because of the tubes themselves, but rather the output transformer ... bad at low freqs due to magnetizing inductance, bad at high freqs due to inter-winding capacitance) and typically higher output impedance (due to low transconductance, low feedback, and output transformer again) ... and of course, the higher output impedance causes measurably worse frequency response when driving complex (loudspeaker) loads.

Any unexplained mysteries? Nope  Despite any claims to the contrary, all sonic differences have been explained by the classic amp measurements : power, gain, frequency response with load (which therefore includes output impedance), noise and distortion.


----------



## FoxPro5

I've tried to debate Werewolf on this a few times. I could not get past the very simple fact that my personal feelings distorted my view of reality. Therefore, I gave up. Not because I lost, but because I wanted to save a **** load of money on my EXTREME SQ AMPS! 

My advice is this. Read what he has to say. Honestly apply what the parameters are for "good sound" while at the same time dropping your ego. If you do this your system will sound better....mainly because The Law of Belief works FOR you not AGAINST you.


----------



## MarkZ

iyamwutiam said:


> Logically - NO DIFFERENCE should yeild a score of chance 50% - any consistent deviation would actually point to a difference. How relevant this deviation is is subject to the arbritrary whim - for example - to say a p of .05 (that it could occur only 5% of the time by chance). In addition - there are multiple studies showing observer bias, testing bias, and most of all believe it or not - for people being tested actully because they are being tested altering their choice. To take the converse argument that anything less than a 100 percent THEREFORE equals 50 percent - is specious and most importantly indicates a spurious motivation rather than an open attempt to gain insight.


Excellent points, and rarely discussed when the challenge is talked about.


----------



## Guest

I always try this, and never get a satisfactory result. Could somebody please consider this question, and maybe humor me with an answer?

I'm going to put forward an hypothesis. All i want, is someone to desribe the scientifically sound _experiment_ that can DISPROVE the hypothesis ... unequivocally, beyond any logical doubt (yes, that's how the method works). Please ... no debates about whether the hypothesis is true or not. I'm looking for the description of an experiment.

The hypothesis is this :

*Operating below clipping, all sonic attributes of an amp can be explained by the classic measurements of : power, gain, frequency response, noise and distortion. If these measurements are the same within any group of amplifiers, all amplifiers in that group will be sonically indistinguishable. In short ... the classic set of measurements sufficiently and completely characterizes the "sound" of an amplifer.*

Once again, what i'm looking for is the *description of an experiment, the outcome of which will disprove the hypothesis*. It's ok not to answer this post, of course! But please don't answer by debating the hypothesis ... that will only demonstrate that the question has not been understood.


----------



## Luke352

werewolf said:


> bad analogies.
> 
> It is not, in my view, perfectly OK to "not believe" in evolution. First, evolution is NOT a belief system, it is a well-proven scientific model. Second, casting it as such causes crazy things to happen, like ignorant school boards preventing evolution from being taught in school.
> 
> .



Actually that is incorrect Evolution IS NOT a proven scientific model, or Fact if you will. It is still officialy a Hypothesis a theory, they still do not have any evidence solid enough to conclusively call it a fact.

Like the Holy Bible's take on the source of life, and just like Evolution you can't conclusively prove it.

It annoy's me when people talk about Evolution as fact, I have no problem with it, they can teach it as much as they like, just do not teach/talk about it as fact when it isnt. Just as when people talk about the Bible as the only truth aswell. Call me a wall sitter or something like that if you will.


Anyway this is a discussion for another thread probably in Open Discussion, so I'll shutup now...

Luke


----------



## Guest

Another question, for those having trouble with the statistical analysis of the results :

Let's say we fill a room with a thousand coin-flippers. They all have ear plugs ... can't hear a thing. In the front of the room, is the amplifier test. Each coin-flipper picks amp-A vs amp-B by flipping the coin. There are 10 successive trials in the test. Are you with me?

I think we can all agree, that the _combined_ success rate will be darn close to 50%. But ... the odds are _really good_ that (at least) one of the coin flippers will get 9 out of 10 right. Agreed?

Here's my question(s):

- Does that dude who got 9/10 right have a coin will exceptional hearing?

- Is the test administrator, who chooses to NOT emphasize this individual's result, guilty of trying to hide something?


----------



## Guest

Luke352 said:


> Actually that is incorrect Evolution IS NOT a proven scientific model, or Fact if you will. It is still officialy a Hypothesis a theory, they still do not have any evidence solid enough to conclusively call it a fact.
> 
> Like the Holy Bible's take on the source of life, and just like Evolution you can't conclusively prove it.
> 
> It annoy's me when people talk about Evolution as fact, I have no problem with it, they can teach it as much as they like, just do not teach/talk about it as fact when it isnt. Just as when people talk about the Bible as the only truth aswell. Call me a wall sitter or something like that if you will.
> 
> 
> Anyway this is a discussion for another thread probably in Open Discussion, so I'll shutup now...
> 
> Luke


You've made a fundamental, classic mistake. I didn't say evolution is "fact". No scientific model is "fact". Science is not a search for truth or fact ... it is simply a search for increasingly accurate models of the universe, designed to explain the past and predict the future.

No scientific model can be conclusively "proven". They all, however, can be readily disproven by experimentation. You misunderstand the entire endeavor of science.

I've said that evolution is very good, accurate scientific model. It explains an ENORMOUS amount of data. Unlike the biblical account of creation (and the creation mythology at the heart of many religions), evolution is NOT a belief system. It is NOT ok to treat it as such.


----------



## MarkZ

werewolf said:


> Another question, for those having trouble with the statistical analysis of the results :
> 
> Let's say we fill a room with a thousand coin-flippers. They all have ear plugs ... can't hear a thing. In the front of the room, is the amplifier test. Each coin-flipper picks amp-A vs amp-B by flipping the coin. There are 10 successive trials in the test. Are you with me?
> 
> I think we can all agree, that the _combined_ success rate will be darn close to 50%. But ... the odds are _really good_ that (at least) one of the coin flippers will get 9 out of 10 right. Agreed?
> 
> Here's my question(s):
> 
> - Does that dude who got 9/10 right have a coin will exceptional hearing?
> 
> - Is the test administrator, who chooses to NOT emphasize this individual's result, guilty of trying to hide something?


That's why when you pose a challenge with a $10k reward, you don't make it easy to "win" by chance.


----------



## Oliver

I wouldn't blame that coin for crying discrimination!


----------



## Abmolech

> wouldn't blame that coin for crying discrimination!


But does the coin have a sonic signiture? 
I really do enjoy these debates, however argueing with facts is rather a poor framework. The Greeks thought the best form was rhetoric.

Why will my power amplifier have better sonic signiture than yours?


----------



## DS-21

iyamwutiam said:


> Logically - NO DIFFERENCE should yeild a score of chance 50% - any consistent deviation would actually point to a difference.


No. Over time, with infinite n, the results of a repeated random binary choice (same/different, heads/tails, etc.) should converge on 50% for each side. However, we're not talking about infinite n here. We're talking about maybe 75 individual trials for a given test (5 subjects, 15 repetitions) tops. And we have statistical methods to determine how likely it is for a given n that x correct identifications would come about as a result of something other than random chance. (Never mind that given the "night and day" differences routinely reported in treble grain, soundstaging, PRAT, and so on, clearly the pomo "golden ear" side should demand perfect identification every time.)

Don't believe me? We agree that a coin toss is a random event, right? By your logic, any other number besides 37.5 heads, 37.5 tails in 75 tosses would mean that there's some real effect, i.e. something beyond simple random chance, driving the results of the coin toss.


----------



## dbphelps

werewolf said:


> *Operating below clipping, all sonic attributes of an amp can be explained by the classic measurements of : power, gain, frequency response, noise and distortion. *


Let me start by saying I am not trying to start a debate here, but pointing out that you just stated the EXACT REASONS why so many of us feel that certain amps have a sonic 'signature' or 'sound' to them... All of those factors combined make up that signature... As in the design of the pre-amps gain/crossover sections, the input stages, even the power stages and the power supply itself all play parts in defining all those attributes, so ultimately with even small variences you can have a given 'sound' out of a certain amplifier design vs anothers...

Just pointing out the obvious, that is that is what we are trying to poll here is that do people actually feel these things have an audible impact on the amplifiers they choose to run...

The amp challenge attempts to do away with as many of those variables as possible, but ultimately we are not given that kind of choice when purchasing equipment... Ie, outside of a select few amps, we have little to no choice to defeat built-in stages/processing to allow for the highest quality of signal passthrough and ultimately cleanest amplification... (I would like to point out that the latest Zed Audio amplifiers actually have a 'Defeat' mode that gets rid of everything on the pre-amp stage outside of the gain)

Per the 'engineering' and 'scientific' ideals of theory and design, while lofty and appreciated goals, we ultimately, as consumers, are stuck with the implimentation and manufacture of a given product which falls far out of any sort of 'ideal' unless specified as a set of goals per a given products manufacture (speaking, again, directly to Zed Audio products and the explanation that Steve Mantz gives towards his design and build of said products), but outside of a few examples is solely left upon us as consumers to either have faith that the manufacture is using lofty goals and high ideals as benchmarks in thier designs, or with the sad reality of quite a few that they could care less, are looking to be able to quote specs and ride out a warranty period long enough to sell product at the highest markup possible with the lowest cost of production available...

Quite honestly, talking to long-term 'faithful' of 'old-school' amplifiers, it is primarily the well engineered and overbuilt designs that are sought after and even still functioning after 5-10-15+ years, where-as a ton of products just fade into history due to shoddy on-the-edge designs where all output devices are driven near max, lack of proper power output, power supplies that were overdriven, or any other number of barely adequate design and build parameters rendering them no more than a footnote in car audio history...


----------



## Diru

dbphelps said:


> Let me start by saying I am not trying to start a debate here, but pointing out that you just stated the EXACT REASONS why so many of us feel that certain amps have a sonic 'signature' or 'sound' to them... All of those factors combined make up that signature... As in the design of the pre-amps gain/crossover sections, the input stages, even the power stages and the power supply itself all play parts in defining all those attributes, so ultimately with even small variences you can have a given 'sound' out of a certain amplifier design vs anothers...
> 
> Just pointing out the obvious, that is that is what we are trying to poll here is that do people actually feel these things have an audible impact on the amplifiers they choose to run...
> 
> The amp challenge attempts to do away with as many of those variables as possible, but ultimately we are not given that kind of choice when purchasing equipment... Ie, outside of a select few amps, we have little to no choice to defeat built-in stages/processing to allow for the highest quality of signal passthrough and ultimately cleanest amplification... (I would like to point out that the latest Zed Audio amplifiers actually have a 'Defeat' mode that gets rid of everything on the pre-amp stage outside of the gain)
> 
> Per the 'engineering' and 'scientific' ideals of theory and design, while lofty and appreciated goals, we ultimately, as consumers, are stuck with the implimentation and manufacture of a given product which falls far out of any sort of 'ideal' unless specified as a set of goals per a given products manufacture (speaking, again, directly to Zed Audio products and the explanation that Steve Mantz gives towards his design and build of said products), but outside of a few examples is solely left upon us as consumers to either have faith that the manufacture is using lofty goals and high ideals as benchmarks in thier designs, or with the sad reality of quite a few that they could care less, are looking to be able to quote specs and ride out a warranty period long enough to sell product at the highest markup possible with the lowest cost of production available...
> 
> Quite honestly, talking to long-term 'faithful' of 'old-school' amplifiers, it is primarily the well engineered and overbuilt designs that are sought after and even still functioning after 5-10-15+ years, where-as a ton of products just fade into history due to shoddy on-the-edge designs where all output devices are driven near max, lack of proper power output, power supplies that were overdriven, or any other number of barely adequate design and build parameters rendering them no more than a footnote in car audio history...



Sounds about right to me....


----------



## backwoods

dbphelps said:


> All of those factors combined make up that signature... .


 
shhhhhhh.....quiet...

none of that is important. The only thing important is that we can manipulate one amp to sound like another in the correct conditions, by eliminating all the possible conflicting variables. 

That is something that I will never argue anymore, because it just is fact at this point in time.

There are all sorts of things people never take into account when buying amplifiers. Like the quality of the build, or the importance of a well designed heatsink. How will this amp react at high temperatures?
People never consider what the internal crossovers are and at what slopes, or maybe even how accurate they are.

Who cares if this amp has a history of shorting at the rca's, or constantly overheats under heavy loads. Why's it matter if it has no thermal protection, or can run itself into the ground at low voltage.

So many people see these threads and go on the incorrect assumption that there is no difference between the flea market amp, and running a well designed amplifier from a reliabe manufacturer. 


About 10 years ago, I had some of the old school lanzar optidrives in my car. I find it funny the way everyone goes crazy over those now. It was a good solid amp, that constantly had thermal issues. If it did not have thermal protection, those amps would have been done in a few months. I can't tell ya how many people would have them shut down because of overheating.

Is that a great amp? to some, but to me, a great amp took that into consideration during the design, and didn't have to add thermal protection later on as a result of inherint problems.


Take this conversation for what it is. Just like a car's main objective is to get you from point A to point B, an amplifiers main objective is to "amplify" a signal. As long as the cars a working correctly, then you will accomplish your objective of getting to point B. Some may be more comfortable, and more capable of alot more drives to point b then others, and can do it with better gas mileage, but even the cheap car, and still accomplish the main task it was intended for.

That is all the amplifier "sound the same" conversation is trying to get across.

And that, is not arguable.


----------



## durwood

That is probably one of the more practical statements I have seen backwoods. That is the partly how I ended up using the amps I did. I have used some great amps over the years, but have experienced all the problem you stated about amps. Now I use amps built over 17 years ago. They don't shut down ever, there are no internal crossovers, nothing but amplifier ina small footprint, big heat sink and when you clip the amp it has no problem letting you know it has nothing more to give you.

Here are some examples of good amps with a few design flaws:
Kicker ZR amps-nice and clean, underated power ratings, but got hot and would shut down sometimes when pushed too hard even though it had a decent ammount of surface area for heatsink-I think it was the the output stage transistors were know for running hot (TIP35,36).

Soundstream Ref-Same deal as the kicker in terms of overheating and being pushed too hard but could also self destruct their power supplies easily.

Blaupunkt classT-Killed 2, I'm assuming by the way of low/unstable voltage or the controller went haywire.


----------



## Oliver

What amps have stood the test of time?


----------



## durwood

Hic said:


> What amps have stood the test of time?


In terms of reliablity or actual popularity?


----------



## Guest

MarkZ said:


> That's why when you pose a challenge with a $10k reward, you don't make it easy to "win" by chance.


EXACTLY.


----------



## Guest

Thanks to the scientific method ... including the proper statistical analysis of results ... we can focus on what really matters in selecting an amp, and what doesn't. Without this guiding light, we'd all be blindly searching in the dark, with nothing to guide us but rumors, hearsay and anecdotes.

The amp challenge clearly demonstrates what's sonically significant. This allows us to focus on _only_ the important specs for sonic results. Once we know, with certainty, that the all sonic performance of an amp can be explained by power, gain, freq response, noice & distortion ... we are set free from marketing ******** to the contrary. Don't think any such ******** is out there? Look again ...

And, it allows us to focus on equally important things such as cost, reliability, and warranty.

I've never stated otherwise.


----------



## Oliver

Being able to dish it out, time and time again, over the long haul !

reliable


----------



## Guest

Anyone that thinks it's an "unfair manipulation" of audio power amplifiers to match gains, power and frequency response ... while making sure noise and distortion are below the thresholds of audibility ... doesn't understand the job of an audio amp, much less the importance of controlling variables in a scientific experiment.


----------



## durwood

werewolf said:


> Anyone that thinks it's an "unfair manipulation" of audio power amplifiers to match gains, power and frequency response ... while making sure noise and distortion are below the thresholds of audibility ... doesn't understand the job of an audio amp, much less the importance of controlling variables in a scientific experiment.


I don't think it's "unfair" as far as the scientific experiment goes because I think the way they approached it was correct, I just think it's unfair to the regular consumer who can't take an amp BNIB and defeat things that might not meet the basic specs that cause an amp to be different.



werewolf said:


> Thanks to the scientific method ... including the proper statistical analysis of results ... we can focus on what really matters in selecting an amp, and what doesn't. Without this guiding light, we'd all be blindly searching in the dark, with nothing to guide us but rumors, hearsay and anecdotes.
> 
> The amp challenge clearly demonstrates what's sonically significant. This allows us to focus on _only_ the important specs for sonic results. Once we know, with certainty, that the all sonic performance of an amp can be explained by power, gain, freq response, noice & distortion ... we are set free from marketing ******** to the contrary. Don't think any such ******** is out there? Look again ...
> 
> And, it allows us to focus on equally important things such as cost, reliability, and warranty.
> 
> I've never stated otherwise.


Nice conclusion.



Hic said:


> Being able to dish it out, time and time again, over the long haul !
> 
> reliable


Well to be honest, flip a coin. There are plenty of them, but alot will be install/application related.


----------



## backwoods

I do have to say, that the poll has quite surprised me..

no wonder this is such a pet peeve of our part k-9 friend..


----------



## Guest

backwoods said:


> I do have to say, that the poll has quite surprised me..
> 
> no wonder this is such a pet peeve of our part k-9 friend..


science and religion ... never the twain shall meet 

for the record : the majority of people voting now "believe" there to be a "sonic signature" of amplifiers _not_ explained by power, gain, freq response, noise & distortion ... despite all tests and logic to the contrary. That's what the poll says.

They _don't_ believe it's unfair to match these parameters. They _don't_ believe that matching these parameters is beyond the ability of the average consumer. They _don't_ believe that once the "extraordinary" effort is made to match power and gains, sonic differences disappear.

They _do_ believe that there is something magical and mysterious to the "sound" of amplifiers, not explained by the current state of scientific understanding. They believe in voodoo.


----------



## durwood

werewolf said:


> science and religion ... never the twain shall meet


Not true 



werewolf said:


> it's ... IT'S ... SCIENTOLOGY !!!!
> 
> disclaimer : no offense intended


----------



## MarkZ

werewolf said:


> science and religion ... never the twain shall meet
> 
> for the record : the majority of people voting now "believe" there to be a "sonic signature" of amplifiers _not_ explained by power, gain, freq response, noise & distortion ... despite all tests and logic to the contrary. That's what the poll says.
> 
> They _don't_ believe it's unfair to match these parameters. They _don't_ believe that matching these parameters is beyond the ability of the average consumer. They _don't_ believe that once the "extraordinary" effort is made to match power and gains, sonic differences disappear.
> 
> They _do_ believe that there is something magical and mysterious to the "sound" of amplifiers, not explained by the current state of scientific understanding. They believe in voodoo.


Look at him. He's seething.


----------



## Abmolech

Anybody who has taken a course in marketing understands, Facts and reason are not part of the advised prescription.

The poll demonstrates, marketing know more about how to sell power amplifiers than scientists. 
Now that is real world.

Who believes any of the specifications (Apart from wattage at a certain voltage) put about an amplifier is useful information?


----------



## JAG

backwoods said:


> I do have to say, that the poll has quite surprised me..
> 
> no wonder this is such a pet peeve of our part k-9 friend..


The poll results does NOT actually suprise me. There are simply too many of us who have done absolutely nothing more than change out like powered amplifiers , and heard their sound characteristics change completely. Science can not argue away experience , and no ... I do NOT believe in voodoo


----------



## Guest

AVI said:


> The poll results does NOT actually suprise me. There are simply too many of us who have done absolutely nothing more than change out like powered amplifiers , and heard their sound characteristics change completely. Science can not argue away experience , and no ... I do NOT believe in voodoo


Yes, you most certainly do believe in voodoo.

Otherwise, you would COMPLETELY understand that simply "swapping" out "like powered" amplifiers in NO way rules out poll-option B. Poll-option B CANNOT be ruled-out, and option C embraced, unless an effort was made to _measure_ gains, frequency response, noise and distortion as the cause of any perceived (real, or otherwise) sonic differences. You would also know, that unless you were unaware that the swap took place, there's a whole 'nother category of variables that are left uncontrolled.

Yes, you most certainly do believe in voodoo


----------



## MIAaron

I recommend the werewolf amps have shrunken heads for gain knobs.


----------



## MarkZ

AVI said:


> The poll results does NOT actually suprise me. There are simply too many of us who have done absolutely nothing more than change out like powered amplifiers , and heard their sound characteristics change completely. Science can not argue away experience , and no ... I do NOT believe in voodoo


Reread selections A through C again. Even if you believe that some amplifiers sound different from others, you should still vote for B *unless* you believe that the difference cannot be measured by modern technology. And since we all (hopefully) know that electricity can be measured with extremely high precision, then the only conclusion you could come to is that another force besides EM is acting on the speaker. So, like, the amplifier is sending "vibes" down the wire too.

Yes, you C-voters _should _be embarrassed.


----------



## durwood

Voodoo Amp


----------



## npdang

AVI said:


> The poll results does NOT actually suprise me. There are simply too many of us who have done absolutely nothing more than change out like powered amplifiers , and heard their sound characteristics change completely. Science can not argue away experience , and no ... I do NOT believe in voodoo


How many times have we been fooled by our own senses though? In my book anecdotal experience just isn't compelling enough evidence to draw conclusions from... I'm sure we've all seen the trick where a ball appears to roll uphill against the force of gravity...


----------



## JAG

npdang said:


> How many times have we been fooled by our own senses though? In my book anecdotal experience just isn't compelling enough evidence to draw conclusions from... I'm sure we've all seen the trick where a ball appears to roll uphill against the force of gravity...


But for months at a time ? I've heard the music just dissapear , and stay un-enjoyable for extended peroids of time , until something different was introduced back into the mix ....
Now if you'll excuse me , I must go mix up some powdered puffer fish , and stir my cauldren ...


----------



## Guest

AVI said:


> But for months at a time ? I've heard the music just dissapear , and stay un-enjoyable for extended peroids of time , until something different was introduced back into the mix ....
> Now if you'll excuse me , I must go mix up some powdered puffer fish , and stir my cauldren ...


AVI, you know i love ya 

But to anyone who voted poll-option C, please ... Please ... PLEASE ... give some serious consideration to this simple question :

*How does one DEFINITIVELY rule out option B ???????*


----------



## FoxPro5

werewolf said:


> AVI, you know i love ya
> 
> But to anyone who voted poll-option C, please ... Please ... PLEASE ... give some serious consideration to this simple question :
> 
> *How does one DEFINITIVELY rule out option B ???????*


Mr Wolf,
In your opinion, can sonic signature be quantified?

Also, you believe that sound quality is relative or absolute?

Just curious of your opinion. Thx.


----------



## Guest

B-Squad said:


> Mr Wolf,
> In your opinion, can sonic signature be quantified?
> 
> Also, you believe that sound quality is relative or absolute?
> 
> Just curious of your opinion. Thx.


Answer my question first ... then i promise to answer yours


----------



## backwoods

werewolf said:


> *How does one DEFINITIVELY rule out option B ???????*


In defense of those voting C, I do not know of a time during use where option B is feasible.


----------



## Oliver

I think they found with the amp challenge, that all amps sound different...unless someone makes them all sound the same and offers you $10,000.00 to prove that you can hear a difference


----------



## Guest

The only mystery about "amp sonics" to me is this ... why do i _still_ participate in this nonsense?

I'm out  i'm sure so very many will be sad to see me go ...


----------



## FoxPro5

werewolf said:


> Answer my question first ... then i promise to answer yours


Doesn't seem possible to disprove that hypothesis given what we know and how we know to test it (ie ABX switching). Plus you'd have to generate a ton of statistical power which kind of removes practicality from the mix.  

So my answer is:


----------



## Oliver

The Human factor is the "WILD" card here.

Scientifically, Werewolf is correct ! In your heart you all know it.

Is gravity a law?

Are death and taxes guaranteed?

It's all relative !!


----------



## chadillac3

werewolf said:


> The only mystery about "amp sonics" to me is this ... why do i _still_ participate in this nonsense?
> 
> I'm out  i'm sure so very many will be sad to see me go ...


Because you're a man of science and the fact people choose to ignore it drives you to drink.  You know you'll never make them change their mind, but it's important enough to you to not just let it go.


----------



## npdang

AVI said:


> But for months at a time ? I've heard the music just dissapear , and stay un-enjoyable for extended peroids of time , until something different was introduced back into the mix ....
> Now if you'll excuse me , I must go mix up some powdered puffer fish , and stir my cauldren ...


Lol 

I don't doubt your experiences... just the conclusions that are drawn from th em. I think that's what this whole thread is about really.


----------



## Dangerranger

I simply cannot trust any human's ability to determine such things without objectivity anyway.

For example, in my workplace we manufacture plastic (packaging film, stretch/shrink wrap, diaper film, mulch, etc.). In order to get a consistent gauge, we have to adjust the die of the machine via bolts, one bolt per inch, in which it's a 96" die. Now back in the day prior to these gauging systems, we had to adjust these by hand. We had no scanner, operators had to feel the rolls and look at the sheet to decide where to adjust this and how much. The adjustments you made could easily be verified by taking samples and using a scale to measure the gauge of the film. People would look at the sheet and swear up and down it needed no adjustments, it looked and felt smooth as glass and consistent. Realistically most operators were doing good to get it within a 5% variance, the very best ones MIGHT be able to get around a 3% variance on a good day and relying a LOT on measuring samples to give them an idea, but they couldn't do it on their own.

We add these gauging systems, and the variances they couldn't detect before became apparent. Before then, they couldn't see or feel a difference on their own, but if the scanner said it was, say, 5% high, and they then felt the rolls and used that reference, they could now see what they were missing before. 

Then we connected gauging systems to automatic dies that adjust the gauge for you, and we are capable of getting this well below a 1% variance.

Amazing what objectivity can do. It may seem irrelevant, but realistically it isn't. We're talking about the fact that people could use the senses of sight AND touch and still not be able to get it right, even qualified people that have been doing it daily for 20 years or more. And our sense of hearing is realistically dumber than our sense of sight or touch, much less the two of them combined. And our knowledge of a person's ability to detect distortion at low levels makes me less confident.


----------



## dbphelps

Ok, I think we got two different set of topics here, and it *may* be attributed to 'not reading closely enough', but ideally a 'trick' poll is pretty much worthless, and per werewolfs and the 'idealist' viewpoint this is nothing more than a 'trick' poll...

What I was referring to, and I am certain what everyone else that voted for 'C' was referring to is that regardless of 'a watt is a watt' we have very little opportunity to buy 'just a watt' when it comes to amplifiers...

I will not argue the scientific side that werewolf is so hard pressed to argue, as he is quite good as stating irrefutable scientific 'fact', 'hypothesis' and 'proof', but what I am bringing to this discussion is that we all live in the 'real world' where not everyone has access to a million dollars worth of testing equipment, labs the size of a sams clubs or connections into the engineering/manufacturing/scientific world that allows us to quantify and measure every little variable of every product we own, thus we are left with feedback systems and our own senses to determine what we do and do not like in lieu of being able to make imperical analysis and decision within controlled settings...

Ideally, yes if you can bypass/fix all of the things that make amplifiers what they are to the consumer you could say every amp is the same, but in reality (key term here, reality of the consumer and his/hers limited resources), you can percieve different sonics of different amplifiers if you do something as simple as 'gain setting' (which is what the largest majority is only able to accomplish, as in being able to set the gain of an amplifier based upon a max input signal to prevent clipping), in which case the amplifiers with better designs that are overbuilt will usually sound better than amplifiers with minimalistic builds of the same rating (ie both amps rated at 50x2, but one putting out 120x2 vs 55x2 for simplistic example), due heavily to the underrating of the first amp... Now add in better input/gain/crossover stages that don't 'color' the sound and whichever amp sounds better regardless of the power output will be the one chosen by the end user... THAT is the heart of why people choose 'C', not because they are arguing the 'trick' question, but because that is how they read the question... Again a totally different viewpoint based on a very simple, but overlooked, symantec...

I am guilty myself of not reading the question properly, but to my own defense I was way overtired and the main question posed in the title of this thread was what I was answering to, and regardless of the poll options itself, I *still* firmly stand by the assertation that of the products produced in teh marketplace, being untouched and unmodified, that you will find plenty that have a certain sonic signature to them out of the box... I am certain hardly anyone can argue that, and that is the HEART of the debate, that it is not an engineering question, but a consumer question at hand, and based upon the viewpoint of the consumer, not the engineer/scientist, we have to deal with the reality of buying something others engineer/design/build and produce...

I feel werewolf at times goes too far in trying to prove his point scientifically and does not appreciate others have less of a scientific background and are not on the same page he is arguing things about... There are many viewpoints and the hardest thing for scientific types is being humble enough to put themselves on others levels and educating them while getting thier point across without being antagonistic, pompous, belittleing, rude, obnoxious and at times donwright arrogant... Ideally I am pointing out the biggest difference in 'intelligence' vs 'wisdom' as the most wise does not need the most intelligence, just have the ability to weigh the knowledge they do have and apply it in the most effective, productive and consistent manner with the ability to constantly be learning, growing and changing thier means and methods to take advantage of new knowledge as it becomes available... The hard scientific types are some of the least productive in regards to producing things the rest of us can actually use, for that we have engineers... And thus begins the never-ending cycle of applied vs theoretical results and the contention that everything *should* be what is calculated...


----------



## JAG

Here is another way of refraining the original question .....
Do I believe , if I were to remove the Arc Audio SE amps from my system , and replace them with another brand's EQUAL POWERED amps , and level match them exactly , they would sound the same ? No damned way. I've tried it MANY , MANY times in the past 23 years , with MANY , MANY systems in different cars , and know what ? They do indeed most often sound noticably different.


----------



## MarkZ

dbphelps said:


> Ideally, yes if you can bypass/fix all of the things that make amplifiers what they are to the consumer you could say every amp is the same, but in reality (key term here, reality of the consumer and his/hers limited resources), you can percieve different sonics of different amplifiers if you do something as simple as 'gain setting' (which is what the largest majority is only able to accomplish, as in being able to set the gain of an amplifier based upon a max input signal to prevent clipping), in which case the amplifiers with better designs that are overbuilt will usually sound better than amplifiers with minimalistic builds of the same rating (ie both amps rated at 50x2, but one putting out 120x2 vs 55x2 for simplistic example), due heavily to the underrating of the first amp... Now add in better input/gain/crossover stages that don't 'color' the sound and whichever amp sounds better regardless of the power output will be the one chosen by the end user... THAT is the heart of why people choose 'C', not because they are arguing the 'trick' question, but because that is how they read the question... Again a totally different viewpoint based on a very simple, but overlooked, symantec...


But that outlook evades the issue of repeatability. Ok, so in the "real world" gain settings will be less precise and people might be able to note a difference. Or the crossovers may have different Qs, and people might be able to note a difference. But should we then conclude that amp A has a different "sonic signature" from amp B? Of course not, because another user may buy both amplifiers, only this time he happened to set the gains differently and didn't use the built-in crossovers. The "signatures" in his case may be the exact opposite of the original user's, simply because he didn't turn the knobs the same way. That's why the "watt is a watt" crowd is emphasizing that we _identify_ the source of any such differences, rather than proclaim that you'll never hear a difference under real world operation. The important point here is that we can make one amp sound like another by tinkering with (or bypassing) the settings.

By the way, I know it's often said that good amps tend to be underrated, but in my experience this isn't usually the case. For example, the much coveted Zed amps tend to do what they're rated to do (at least my ESX Quantum and Minilith). Personally, I prefer _accurate_ ratings over misleading ones, even if the misleading one is conservative. A manufacturer gets bonus points in my book if they show various ratings based on supply voltage and impedance.



> I feel werewolf at times goes too far in trying to prove his point scientifically and does not appreciate others have less of a scientific background and are not on the same page he is arguing things about...


I actually feel the opposite way. I think he attempts to dumb things down for the non-scientist. His questions often illuminate the logic behind the issue rather than the technical aspects. In fact, in threads like these he tends to refrain from using lots of engineering jargon. You don't need a degree in physics to answer the question he keeps asking: "how does one definitively rule out option B"?


----------



## DS-21

werewolf said:


> The only mystery about "amp sonics" to me is this ... why do i _still_ participate in this nonsense?
> 
> I'm out  i'm sure so very many will be sad to see me go ...


Same here. As a parting shot, I really have to wonder if all of the people prattling on about "amp sound" actually have functioning ears, or if they just like shiny things.


----------



## squeak9798

dbphelps said:


> I will not argue the scientific side that werewolf is so hard pressed to argue, as he is quite good as stating irrefutable scientific 'fact', 'hypothesis' and 'proof', but what I am bringing to this discussion is that we all live in the 'real world' where not everyone has access to a million dollars worth of testing equipment, labs the size of a sams clubs or connections into the engineering/manufacturing/scientific world that allows us to quantify and measure every little variable of every product we own, thus we are left with feedback systems and our own senses to determine what we do and do not like in lieu of being able to make imperical analysis and decision within controlled settings...
> 
> Ideally, yes if you can bypass/fix all of the things that make amplifiers what they are to the consumer you could say every amp is the same, but in reality (key term here, reality of the consumer and his/hers limited resources), you can percieve different sonics of different amplifiers if you do something as simple as 'gain setting' (which is what the largest majority is only able to accomplish, as in being able to set the gain of an amplifier based upon a max input signal to prevent clipping), in which case the amplifiers with better designs that are overbuilt will usually sound better than amplifiers with minimalistic builds of the same rating (ie both amps rated at 50x2, but one putting out 120x2 vs 55x2 for simplistic example), due heavily to the underrating of the first amp... Now add in better input/gain/crossover stages that don't 'color' the sound and whichever amp sounds better regardless of the power output will be the one chosen by the end user... THAT is the heart of why people choose 'C', not because they are arguing the 'trick' question, but because that is how they read the question... Again a totally different viewpoint based on a very simple, but overlooked, symantec...


From what I read of those statements....you are basically saying that because most consumers don't have the equipment or knowledge to properly match amplifiers they hear different sonic signatures in the amplifiers. At which point you are admitting you aren't hearing differences in the amplifier's themselves but rather due in the setup of the amplifiers.

So I guess I really don't see how that proves any points, other than two amplifiers setup differently will sound differently.....which I don't think was ever really a point of contention.

Maybe I misread it though.......


----------



## durwood

AVI said:


> Here is another way of refraining the original question .....
> Do I believe , if I were to remove the Arc Audio SE amps from my system , and replace them with another brand's EQUAL POWERED amps , and level match them exactly , they would sound the same ? No damned way. I've tried it MANY , MANY times in the past 23 years , with MANY , MANY systems in different cars , and know what ? They do indeed most often sound noticably different.


There is more to it then level matching. Has anyone noticed the absence of some numbers from the freq resp ratings on some brands of amps? I remember a time when the frequency response listed a tolerance. Some were +/-3db, some were 0/-1db, +/-1db, and how much change can the human hearing distinguish? Guess where the response suffers, usually at the ends-the low end the high end. Frequency response is one of those that has to meet a certain criteria in the challenge. So, even if you gain match, there could be and is probably one or more factors at play.


----------



## Oliver

In regards to *, to oversimplify, if you measure a cup of water, say 8 oz, would you have 8oz?

If you had a Lb of feathers, say 16 oz, would you have a Lb of feathers?

If you could set the parameters of an amplifier to measure exactly the same as another amplifiers, could you hear a difference?

In regards to , all parameters set with various electronic meters to within the closest possible amount, could you still discern a noticeable difference between a McIntosh and a Boss if they weren't allowed to be pushed into clipping...so basically no way to give away who they were!*


----------



## WLDock

Well, I did not care to read through this entire post but...

A basic resistor will have differences over another resistor when measured from cold to hot....so a group of components in a circuit will most definitely have a measured difference.

Can we hear differences in amps? Maybe...

We all know that amps sound different when they are under strain....some handle it gracefully and some just wine and strain like a crying baby.

I think that really is all that needs to be said..

P.S.
Just like some people have incredible brains and can do incredible things that a normal person cannot....I think some have much better hearing than others....some can hear minute differences where others cannot even hear differences in speakers or differences in metal dome tweeters or soft domes etc....


----------



## MarkZ

WLDock said:


> Well, I did not care to read through this entire post but...
> 
> A basic resistor will have differences over another resistor when measured from cold to hot....so a group of components in a circuit will most definitely have a measured difference.


That's true. But you can't just add up all the differences and assume that'll make its way into the output. Like I've said before, amps are designed to make differences in values irrelevant. That may not make much sense to people without experience with circuits, but global and local feedback allow you to use wide ranges of values for most parts of the amplifier.


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## Oliver

If you are familiar with auto racing, you may have seen a race of champions where all the vehicles are set up as close to the same as possible.

Then it comes down to who teams up with who as no vehicle has an edge.


----------



## DonutHands

oops, didnt notice how old this was


----------



## Whiterabbit

damn. i was hoping noone would respond, and let it die again.


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## Bluto Blutarsky

die again


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## Oliver

Concerning amplifiers 

Merci pour vos conseils ...Mais la situation à empiré , j' avais trouvé comment installer second Life par Synoptique ! Mais voilà il mettait 25 minutes pour l' installer et ça m' a semblé bizarre pour un paquet de 52 MB ...J' ai donc intérrompu et depuis grosse gaffe ! (il en faut quand on apprend lol) Plus moyen d' acceder au gestionnaire de paquet synaptique ... 
Voiçi ce qui marque . 
"une erreur à eu lieu ,je dois réinstaller le paquet secondlife mais je n' ai pas trouver l' archive ...Veuillez prévenir update-manager et envoyer le message précédent " 

ET ceci m' empêche ainsi de m' en servir ... 
j' ai déjà rentrer la commande suivante : sudo apt-get purge secondlife remove 
il me répond Purge as valable ? 

Alors que faire ?


----------



## ca90ss

Hic said:


> Concerning amplifiers
> 
> Merci pour vos conseils ...Mais la situation à empiré , j' avais trouvé comment installer second Life par Synoptique ! Mais voilà il mettait 25 minutes pour l' installer et ça m' a semblé bizarre pour un paquet de 52 MB ...J' ai donc intérrompu et depuis grosse gaffe ! (il en faut quand on apprend lol) Plus moyen d' acceder au gestionnaire de paquet synaptique ...
> Voiçi ce qui marque .
> "une erreur à eu lieu ,je dois réinstaller le paquet secondlife mais je n' ai pas trouver l' archive ...Veuillez prévenir update-manager et envoyer le message précédent "
> 
> ET ceci m' empêche ainsi de m' en servir ...
> j' ai déjà rentrer la commande suivante : sudo apt-get purge secondlife remove
> il me répond Purge as valable ?
> 
> Alors que faire ?


Thank you for your councils… But the situation with worsened, I had found how to install second Life by Synoptique! But here it spent 25 minutes to install it and that seemed to me odd for a package of 52 MB… I thus have intérrompu and since large blunder! (it of is necessary when lol is learned) Plus average to reach to the synaptic manager of package… 
Voiçi what marks. 
" an error with take place, I must reinstall the package secondlife but I do not have to find the file… Want to warn update-manager and send the preceding message " 

AND this thus prevents me to be useful to me about it… 
I have already to return the following order: sudo apt-get purging secondlife remove 
he answers me Purge valid ace? 

Whereas to make?


----------



## cvjoint

Whiterabbit said:


> damn. i was hoping noone would respond, and let it die again.


Never! This thread will never die!


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## Fixtion

This has poorly written ALL over it. ALL the answer contain the world ALL, bah. I wonder if whoever wrote this is a professor or educator of some sorts. lol...worthless two cents. I voted, amps have their own sonic qualities to them if they don't they sound familar to others. <---- Another poorly written statement

-Fixtion


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## FoxPro5

Not all amps have finger prints, but I've had a few that have shown up with them. Kind of takes away from the new toy excitement and all. You know, you open up the box and some dude at the factory (probably named Sonic or something) didn't have the decency to even wipe it down before putting it in the box.  

Then YOU put your greasy finger prints on it and low and behold it slips out of your hands and drops on the ground. Well, I guess that's not such a bad thing because at least you know how it sounds.


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## Megalomaniac

I voted third category, because I was able to tell my Zapco amp from an eD amp easily. It blew it away completely IMO. I dont know if its becaus eof symbilink, but whatever zap does keep doin it 

cheers


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## soven

Megalomaniac said:


> I voted third category, because I was able to tell my Zapco amp from an eD amp easily. It blew it away completely IMO. I dont know if its becaus eof symbilink, but whatever zap does keep doin it
> 
> cheers


Read the second option. You managed to disable filters, eq,gain match etc etc? If you did not manage to do those then you should have voted option 2 like many others should have.


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## Guest

soven said:


> Read the second option. You managed to disable filters, eq,gain match etc etc? If you did not manage to do those then you should have voted option 2 like many others should have.


EXACTLY !!

The ONLY way to eliminate, or discount, option #2 is to be certain that the amps in question do, indeed, MEASURE the same.

For anyone that voted option #3 ... you do realize that option #2 means that amps sound different, right?

Edit : In other words, if you swap-out amp "A" for amp "B" and hear a difference ... option #2 acknowledges it, option #2 _agrees_ with you, and most importantly ... option #2 _explains why_


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## Abmolech

This proves at least 50 percent of the people are half right, the other half have been out witted.


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## Megalomaniac

soven said:


> Read the second option. You managed to disable filters, eq,gain match etc etc? If you did not manage to do those then you should have voted option 2 like many others should have.


hmmm you have stumped me now. Maybe it should have been worded differently...i feel silly now if im hearing it right.

But i still feel that 2 amps wont sound the same... :blush:


----------



## Guest

Megalomaniac said:


> hmmm you have stumped me now. Maybe it should have been worded differently...i feel silly now if im hearing it right.
> 
> But i still feel that 2 amps wont sound the same... :blush:


everyone agrees with you  two amps will _not_ sound the same ... option 2 agrees, and explains why.

If you swap amps and hear something different, you would only pick option 3 if you were _convinced_ ... scientifically, and logically ... that the amps indeed measured the same (same gain to within 0.25dB, same frequency response over 20kHz, etc). Only then do we need to invoke voodoo and magic as explanations  

The only way to rule out the current abilities of science, is to actually eliminate all possibilites _explained_ by science first 

By way of analogy : you ride in one car, and feel it's faster than another. To verify, you might actually find a way to objectively _measure_ the performance. Then, you might try to understand the drivetrains (torque, gear ratios), weight, suspension in order to understand _why_ one car is faster. This is what option 2 says. Does that mean option 2 says that all cars are equally fast? Or, does it say that different cars are capable of different accelerations, top speeds, etc ... but we can measure, and explain why.
Option 3 would approach this situation differently ... option 3 would say, "i know car A is faster ... and it's beyond the possibility of measurement. Furthermore, there's no way science can explain _why_ car A is faster. I just know it's true ... ride in car A, it's faster! That's all i need to know ... so i pick option 3"


----------



## FoxPro5

It's impossible to _know_ that two amps do not sound the same. Because in order to say so, you must have had to listen to at least two.  However you can certainly hear (no pun intented) others talk (or write) about it all day long. Herein lies the problem with this damn debate. 

One doesn't know anything in a field of polarity/the Universe/time-space/relativity without knowing of or about something else. To be technically specific, you have to study Plank or Schroedinger, I suppose. 

Hey, is that a particle or wave? Hey, does that amp sound like this other one? YOU DECIDE!  That decision is going fall into the category of religion, more than it will in the category of science. WW says this all the time, so it's not like what I'm saying is novel...I'm just reiterating it, really. For what reason? Because I like to hear myself talk and then write it on a computer screen. 

But to take it one step further, you have to understand how the human belief system(s) operate to really settle the debate for yourself. Point is, stop believing and start questioning. I guess......


----------



## fredridge

has anyone ever tried to exchange two of the exact same amps and see if there is a difference?


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## Guest

fredridge said:


> has anyone ever tried to exchange two of the exact same amps and see if there is a difference?


do those two amps have gain knobs? If the answer is yes, then the answer to your question will be yes ... and that's not a matter of belief or opinion 

Unless, of course, you use a dmm or scope to set gains to within 0.25dB. Lining up the gain knobs by eye won't quite get you there ... 

Edit : that's an "option 2" answer, by the way


----------



## Oliver

This debate originally started with amp "A" and amp "B", upon noticing the striking similarities in sound Richard Clark made a class A/B amp, and that is the rest of the story


----------



## FoxPro5

Hic said:


> This debate originally started with amp "A" and amp "B", upon noticing the striking similarities in sound Richard Clark made a class A/B amp, and that is the rest of the story


Now that's pretty damn funny! 

I have two identical amps (DLS A2) vertically bi-amping my tweeters and my midrange (one on the left, one on the right). They are level matched with a DMM to .1v. All crossovers disabled. Imput voltage same within .1v. No clipping on the scope. No audible noise detected. 

When I play any of the Autosound 2000 disks they sound exactly the same! Why is this?


----------



## Guest

fredridge said:


> has anyone ever tried to exchange two of the exact same amps and see if there is a difference?


Option 1 answer : Even with the gain knobs set _way_ different, the amps sound the same ... can't tell one from the other. Isn't that what RC says?

Option 3 answer : With the knobs each set at about a quarter turn, the amps sound different. And all current scientific thought is at a loss to explain why.


----------



## cvjoint

Let me do Option 2:
I've noticed a difference in sound after I swapped my amp. I went ahead and measured the frequency response, if there were any built in eq. wonders that were not defeatable I sliced the thing open and performed surgery, matched the gain to 4 decimals. Furthermore, before I went about with a blanket statement saying all amplifier differences can be accounted for using these few easy steps I tested all types of amplifiers, all classes, and all designs and achieved similar results. I then went ahead and picked option 2.


----------



## Guest

cvjoint said:


> Let me do Option 2:
> I've noticed a difference in sound after I swapped my amp. I went ahead and measured the frequency response, if there were any built in eq. wonders that were not defeatable I sliced the thing open and performed surgery, matched the gain to 4 decimals. Furthermore, before I went about with a blanket statement saying all amplifier differences can be accounted for using these few easy steps I tested all types of amplifiers, all classes, and all designs and achieved similar results. I then went ahead and picked option 2.


How many users who report hearing a difference after an amp swap actually measure the frequency response, to rule that out? That's the only way to rule out option 2  Or ... can we rule out option 2 by "belief" alone?

And who ever opened an amp to perform surgery in order demonstrate that a few simple specs completely characterize an amp's sound? Certainly never been a part of the RC challenge, as far as i know. All you need to do is put an EQ in the system to equalize frequency response ... oh, and you get to choose which amp to add the EQ to 

Nobody just wants to "believe" that the wonderful sonics from their megabuck amps are due to simple frequency response differences ... nope, gotta something more mysterious than that 

Edit: It's not a blanket statement to suggest that all amp "sonics" are accounted for by power, gain, frequency response, noise and distortion when : linear system theory dictates it to be true, and all controlled listening tests continually fail to suggest anything contrary.

Plus, i already did option 2


----------



## Guest

Very simple question for the option three dudes :

How do you know the differences you heard can NOT be explained by : power, gain, frequency response, noise and/or distortion?

How do you know?

I can decisively, completely rule out option 1 : Two amps with gain settings vastly different will sound different. No doubt about it ... i can pick one out, over the other, a thousand times in a row. So can anyone here. Therefore, we can rule out option 1 ... all amps do _not_ sound the same. This conclusion will easily withstand any laws of science, or rigors of logic we care to apply.

How do we rule out option 2 with the same inescapable logic?


----------



## Abmolech

I posted in a thread that NONE of my DLS A3 with incremental serial numbers sounded the same out of the box. (I have seven, two more are non sequential)
This is real world testing. 
I have done this so I am not playing fun and games.
I guarantee you my other two would not sound the same. (Not tried)

If I went to another store, the next seven DLS A3 would sound different as well. (No I am not stupid enough to do this)

IS this because even if I sequential number amplifiers they will have different sonic signatures, or is it because out of the box, the gains crossovers are set differently?
IS this a valid test?
And if so what does it prove?

Does the amplifier challenge only work if I have "fancy equipment" that the average punter would not purchase or even know how to use?

Or do I continue going from store to store in the search of the "holy grail" of sonic signatures? 
ouroboros 

Another thought to ponder.
IF I suggest my power amplifier will ALWAYS sound better than yours, even you would agree that this amplifier is better.
What sort of test do you think would be fair?
(people that understand the principle need not apply )


----------



## cvjoint

ahhh but equalizers and processors can add some noise too now can't they? Are we controlling for variables by introducing more boxes in the signal path?

I'm not saying manufacturers don't mess with the flat response to trick its client, they may very well be doing so. 

A leveled play field is all I recommend. You say all option 3 supporters should first conduct a carefully planned out/costly/scientifically correct/time consuming experiment to back their choice. Then why shouldn't option 2 upholders do the same, with the addition of testing out every possible amplifier characteristic to maintain credibility under any circumstances?


----------



## Abmolech

> A leveled play field is all I recommend. You say all option 3 supporters should first conduct a carefully planned out/costly/scientifically correct/time consuming experiment to back their choice. Then why shouldn't option 2 upholders do the same, with the addition of testing out every possible amplifier characteristic to maintain credibility under any circumstances?


Possibly because if we understand linear response systems, we don't need to measure every cable and component. Thats what manufactures specifications are for.
IE the variations in manufactures tolerances are not enough to effect an audible outcome (Good design)

Do you measure and calibrate your oil and filter on every change? Or is the variation not enough to effect the outcome? (Batch to batch)


----------



## cvjoint

Depends what you mean by manufacturer's specifications. If you are referring to the worthless spec sheet that comes with the amp then I will beg to differ. I wouldn't use that sheet for anything more than a paper airplane. If we are skeptical about a manufacturer boosting the low end to give more appeal to their product then what would stop them from generously rounding off their spec sheet numbers?


----------



## Abmolech

I meant the supplier of the parts.

If I knew enough about the power amplifiers fitness for the task, and I did some basic tests to assure myself that it is not faulty. If I heard a response anomalies I could do one of several things.
1/ Decide this amplifier had some new "features" that I can not explain.
2/ Recheck my setup to assure myself that it is level matched and crossovers are set the same. If I still heard a difference, I could swap the previous power amplifier back, and retry. If I still heard a difference I would measure the response output of both. If both measured the same and I still heard a difference, then this would make me very excited, because I have found something outside of our ability to measure.
IF I could replicate this same test to our physics department to their satisfaction, we would be on one of the greatest break through of this century. IE we still can't measure the electrical input that would cause a radiating driver (motor) to function.

Point
The test provides a means that you can assure yourself that any response difference can be measured and accounted for. If this is the case you now have the means to replicate ANY sonic signature within the manufactures specifications.You can now buy with some degree of confidence. 
Reliability, ascetics and fit for the task obviously will still play a major role. 
Lets face it most of don't buy a watch because one can keep the time better than another..


----------



## Guest

cvjoint said:


> ahhh but equalizers and processors can add some noise too now can't they? Are we controlling for variables by introducing more boxes in the signal path?
> 
> I'm not saying manufacturers don't mess with the flat response to trick its client, they may very well be doing so.
> 
> A leveled play field is all I recommend. You say all option 3 supporters should first conduct a carefully planned out/costly/scientifically correct/time consuming experiment to back their choice. Then why shouldn't option 2 upholders do the same, with the addition of testing out every possible amplifier characteristic to maintain credibility under any circumstances?


read option 3 again ... you must have ruled out all scientific explanations for amplifier sonics, in order to embrace option 3.

Again ... how do you know that the differences you heard can NOT be explained by science?

Linear system theory dictates, and countless controlled listening tests demonstrate, that all amp "sonics" are explained by a simple set of specs. If you hear a difference, how can you possibly dismiss these specs as the valid explanation ... unless you make sure these specs are equalized ?

How do you rule out the scientific explanation, until it's results are comprehended?

Let's say you drop a small rock, and just _know_ that it dropped faster than it should. You didn't measure it's rate of decent ... you just _know_ it fell too fast. You actually _saw_ it fall ... you experienced it! And after all, the test to actually _measure_ its rate of decent is expensive and time consuming. Therefore, you conclude that this rock is _not_ subject to Newton's Law of Gravity. Is that a sound conclusion?


----------



## Diru

werewolf said:


> Let's say you drop a small rock, and just _know_ that it dropped faster than it should. You didn't measure it's rate of decent ... you just _know_ it fell too fast. You actually _saw_ it fall ... you experienced it! And after all, the test to actually _measure_ its rate of decent is expensive and time consuming. Therefore, you conclude that this rock is _not_ subject to Newton's Law of Gravity. Is that a sound conclusion?


Huh?

We know NLoG is not constaint when we bring to bare AE's E=MC^2.

So within reason of perseption, we drop 2 rocks into a pond , one large , one small. Both fall at the same rate as percived by NLoG. Do they both make the same sized splash. 

No....

So why change the rules to fit the game and or test to make an outcome?


Peanutbutter and Jelly?


----------



## Guest

Diru said:


> Huh?
> 
> We know NLoG is not constaint when we bring to bare AE's E=MC^2.
> 
> So within reason of perseption, we drop 2 rocks into a pond , one large , one small. Both fall at the same rate as percived by NLoG. Do they both make the same sized splash.
> 
> No....
> 
> So why change the rules to fit the game and or test to make an outcome?
> 
> 
> Peanutbutter and Jelly?


You bring up a valid point ... well, i mean, needing to invoke general relativity to accurately measure a rock fall into a pond is just about as valid as worrying about skin effect in analog audio cables    

I like peanut butter and jelly ... just not on the same sandwich


----------



## thehatedguy

Hey hey hey Mr. Cable man...no skin effect in audio cables? Get the hell out of here. Could have sworn I saw an Tributaries ad somewhere talking about skin effect.  Actually I did, but they said it only mattered for video and frequencies of 1MHz and up.

PB&J only works with strawberry jelly though.


----------



## Diru

werewolf said:


> You bring up a valid point ... well, i mean, needing to invoke general relativity to accurately measure a rock fall into a pond is just about as valid as worrying about skin effect in analog audio cables
> 
> I like peanut butter and jelly ... just not on the same sandwich



Ohhh I won't go there about audio cables. We'll just say there is a deminishing return. Only how big your pocket book will determin that.


I seen some other stuff in there that I would give creedence to. 

Sure brand A amp sounds the same as another brand A amp[same model also].

Then you get into does brand A sound the same as brand B, sure it could.

Then if you try and compair brands a,b,c,d,f,and g and you adjusted for output, eq`ed for flat. 

Now lets look at the rock and pond, we have rocks that are the same weight and chipped to be about to same roundness. Now drop them into the pond. 



Wasn't there a Reeses PB&J cup.....


----------



## FoxPro5

The only thing constant or consistent in this Universe is the fact that peanut butter and jelly in the same jar sounds absolutely disgusting.


----------



## chad

B-Squad said:


> The only thing constant or consistent in this Universe is the fact that peanut butter and jelly in the same jar sounds absolutely disgusting.


Does not matter anymore, kids cannot take PB&J to school because some other kids seem to have developed an insane PB allergy that seemd to not exist when I was a kid  

Whiners


----------



## Diru

werewolf said:


> You bring up a valid point ... well, i mean, needing to invoke general relativity to accurately measure a rock fall into a pond is just about as valid as worrying about skin effect in analog audio cables
> 
> I like peanut butter and jelly ... just not on the same sandwich





Diru said:


> Ohhh I won't go there about audio cables. We'll just say there is a deminishing return. Only how big your pocket book will determin that.
> 
> 
> I seen some other stuff in there that I would give creedence to.
> 
> Sure brand A amp sounds the same as another brand A amp[same model also].
> 
> Then you get into does brand A sound the same as brand B, sure it could.
> 
> Then if you try and compair brands a,b,c,d,f,and g and you adjusted for output, eq`ed for flat.
> 
> Now lets look at the rock and pond, we have rocks that are the same weight and chipped to be about to same roundness. Now drop them into the pond.
> 
> 
> 
> Wasn't there a Reeses PB&J cup.....




I can't believe I did that. 

You see I changed the test. I didn't mean to, but it happened. 

Get someone else then put a blind fold on them, then drop the rocks.....[but then again this was under the pretents on a blind listening test]


I know someone made a PB&J jellybean..


----------



## chad

Diru said:


> Get someone else then put a blind fold on them, then drop the rocks.....



Must be in a vacuum because microcurrents of air could alter the fall of one rock


----------



## durwood

I had a crazy physics professor that thought Peanut Butter and jelly slices was a good idea and he spent a whole class discussing it. Guess it wasn't too crazy...http://www.pbslices.com/


----------



## Diru

chad said:


> Must be in a vacuum because microcurrents of air could alter the fall of one rock


If we did that then it will no longer be a blind listening test, if the listener turns blue in the face and dies. It will make the test invalid.



durwood said:


> I had a crazy physics professor that thought Peanut Butter and jelly slices was a good idea and he spent a whole class discussing it.


I'm not that professor, but I am crazy.


----------



## chad

durwood said:


> I had a crazy physics professor that thought Peanut Butter and jelly slices was a good idea and he spent a whole class discussing it.


He/She was advocating conformity, IMHO the fine line between the PB to J ratio is TOTALLY subjective!


----------



## chad

Diru said:


> If we did that then it will no longer be a blind listening test, if the listener turns blue in the face and dies. It will make the test in valid.


Hot Damn, we have discovered an environment for cable testing!


----------



## Chaos

I voted for 2 because it is the most objective statement on the list.

I my experience, I have directly swapped out many amps over the years with immediate & noticeable (albeit subjective) audible results. 

That's not to say that the RC challenge is bogus, or that anybody else doesn't hear what they hear when they change amps, but the fact of the matter is that no setup ever sounds the same twice. Even if the tolerances & performance of the equipment was constant, the person doing the listening & the environment in which it takes place do - so making oversimplified objective statements to the contrary is always a fruitless endeavor.


----------



## Gary S

20 pages of this... forgive me if I don't read them all, I just don't have the patience to read about something I feel I already know enough about... it can get old, you know?!

I worked in the audio business for many years... even worked for JL Audio for a time... so, I have some experience... have heard a lot of audio systems and products over the years.

When I first read about RC's challenge, all my experience told me he was right... solid-state amps with filters off, unclipped, at identical output levels do sound the same. You have to keep in mind something... one of the best midrange drivers I ever heard was said to have a low distortion figure... the distortion was 3%... as you know, the distortion of most modern day solid state amps is well below this. If you crunch the numbers, it's easy to see that it's impossible to hear the lower distortion of the amp through speakers; the speakers mask any minute unclipped distortion an amp makes.

Now, tube amps and pre-amps may be another story... but it's also possible to make a circuit for a solid state amp to make it sound like a tube amp... in fact there was a black box available for the home audio market which did just that.

I think people would get much more fulfillment out of their audio systems if they would put their efforts into more important areas... such as installation quality, system design and tunning, speaker placement, speakers... and perhaps even multi-channel sound. I could put a car in a garage and do work in those areas for months and spend thousands, increasing sound quality week after week... but changing amps would be one of the last things on my mind... and before I would ever actually contemplate doing that, the audio system would sound much better than needed for me.


----------



## typericey

I can't go through 20 pages of this either! But my simple answer to the poll is yes, amps have a sonic signature. I'm pretty confident I can tell the difference between a Pioneer receiver and a pair of Audio Research Reference Dual Monos blindfolded.


----------



## Oliver

typericey said:


> I can't go through 20 pages of this either! But my simple answer to the poll is yes, amps have a sonic signature. I'm pretty confident I can tell the difference between a Pioneer receiver and a pair of Audio Research Reference Dual Monos blindfolded.


This ability will or could earn you "Ten Thousand Dollars"


----------



## t3sn4f2

a$$hole said:


> This ability will or could earn you "Ten Thousand Dollars"


Might wanna tell him no one has ever won the prize, don't wanna get him excited for nothing.


----------



## 60ndown

all an amp is meant to do is 

'amplify the signal'

so, all 'good' amps, 

(good meaning it only amplifies the signal, and doesnt change it) 

sound the same.


----------



## Foglght

So, in the other thread someone posted a FR graph with a Fosgate amp, that showed a slight bump in the lower and upper frequencies. Apparently, this is done on purpose?

Who else does this? Is this common? How would I know? Maybe this is a factor in the "sonic difference."

The only time I ever notice a difference is when I upgrade to an amp that meets or exceeds the power capability of the speaker, so as I am not overheating the amp and making it less efficient, thus putting out less power and causing the speaker to sound like poop.


----------



## t3sn4f2

Foglght said:


> So, in the other thread someone posted a FR graph with a Fosgate amp, that showed a slight bump in the lower and upper frequencies. Apparently, this is done on purpose?
> 
> Who else does this? Is this common? How would I know? *Maybe this is a factor in the "sonic difference."*
> 
> The only time I ever notice a difference is when I upgrade to an amp that meets or exceeds the power capability of the speaker, so as I am not overheating the amp and making it less efficient, thus putting out less power and causing the speaker to sound like poop.


That would be a dominant factor in a sonic differences and a rare one. If you look at amp specs, the frequency response numbers will tell you what you want to know. They will usually be something like 20hz-20Khz (+Xdb,-Ydb) and all will strive for no more then +/- .5db.


----------



## Foglght

t3sn4f2 said:


> That would be a dominant factor in a sonic differences and a rare one. If you look at amp specs, the frequency response numbers will tell you what you want to know. They will usually be something like 20hz-20Khz (+Xdb,-Ydb) and all will strive for no more then +/- .5db.


Yeah, and I've also seen people rating their amps at 5w/channel and they end up being 50w/channel.  

Edit: And I feel that example is a good thing, yet still misleading. I would imagine it was rated that way for competition. I don't feel underrating and overrating are a good idea, because it only furthers my assumption that people are just trying to pull the wool over my eyes with their knowledge and my ignorance. 

So what would cause the sensation of clarity with just an amplifier assuming all the other factors were constant? What in the amp causes the sensation of smoothness?..........and all other factors I hear used all the time to describe different amps. I read quite a few of those online car stereo reviews and feel as though my ears weren't upgraded to hear 1/24 octave differences, which is where in my own mind those subtle differences are shown because of the actual multiple tones in a human voice or a musical instrument. Does that make sense?


----------



## t3sn4f2

Foglght said:


> *Yeah, and I've also seen people rating their amps at 5w/channel and they end up being 50w/channel.
> 
> Edit: And I feel that example is a good thing, yet still misleading. I would imagine it was rated that way for competition. I don't feel underrating and overrating are a good idea, because it only furthers my assumption that people are just trying to pull the wool over my eyes with their knowledge and my ignorance. *
> 
> So what would cause the sensation of clarity with just an amplifier assuming all the other factors were constant? What in the amp causes the sensation of smoothness?..........and all other factors I hear used all the time to describe different amps. I read quite a few of those online car stereo reviews and feel as though my ears weren't upgraded to hear 1/24 octave differences, which is where in my own mind those subtle differences are shown because of the actual multiple tones in a human voice or a musical instrument. Does that make sense?


My comment is backed up countless times on actual home amp measurements, not just manufacturer published specs.


----------



## Oliver

A couple of shots of good whiskey and even your girl will seem smoother


----------



## Foglght

a$$hole said:


> A couple of shots of good whiskey and even your girl will seem smoother


A couple of shots of Whiskey makes everything a little rougher with her.


----------



## chad

I'm watching this thread and poll progress and it amuses me as a scientific person.


----------



## cvjoint

I think this poll will outlive me.


----------



## Oliver

chad said:


> I'm watching this thread and poll progress and it amuses me as a scientific person.


What are you drinking  ?


----------



## br85

I can't believe how many people chose option 3. This is truly a sad indictment for mobile audio.

Onto something a little different, but still on the topic of sonic fingerprint,
recently it has come to my attention that there is the strong belief that class D amplifiers will never truly be able to replicate the class A/B because of a lack of decent *transient response*. Has anyone ever heard this effect/measured it/heard about it from anyone?

It's got me a little bit intrigued.


----------



## Oliver

br85 said:


> I can't believe how many people chose option 3. This is truly a sad indictment for mobile audio.
> 
> Onto something a little different, but still on the topic of sonic fingerprint,
> recently it has come to my attention that there is the strong belief that class D amplifiers will never truly be able to replicate the class A/B because of a lack of decent *transient response*. Has anyone ever heard this effect/measured it/heard about it from anyone?
> 
> It's got me a little bit intrigued.


I liked the way your post started 

If the current offerings were somehow slower, don't you think people would have commented...i.e. my music sounds like a 45 rpm record running at 33 1/3  ?


----------



## Dangerranger

a$$hole said:


> If the current offerings were somehow slower, don't you think people would have commented...i.e. my music sounds like a 45 rpm record running at 33 1/3  ?


lol. I agree

You could hand 99% of people a 1/3 octave equalizer and a phase adjuster (like the one PPI used to make) and let them have at it, run rampant and free, tuning to their ear's liking with no aid from an RTA. Then measure the result and see exactly what they REALLY ended up with. After that, let's see how many have any business fussing about what amplifier sonics they "heard". 

Most of the complaints from the subjective standpoint is, ironically, based on what they've been told from an objective engineering standpoint due to what has been measured, i.e. distortion, crossover distortion of the transistors based on topology, damping factor, slew rate, and the most recent argument: channel separation. Like they'd ever guess it on their own. Nevermind that they didn't build a subwoofer box that was properly sized for optimal response in the environment, or that the midbass drivers aren't exactly right for the door cavity (which is the case 99% of the time just because you're not going to get a driver specific to the car itself). No, I need an amplifier with a higher damping factor, that's why my midbass is resonant and sloppy sounding.


----------



## Abmolech

Its about as interesting as watching paint dry.

The fool and his money are soon departed.

The sorriest indictment is the use of this forum (advanced) for a topic of this nature. This belongs in below basic.


----------



## dozy_production

Abmolech said:


> Its about as interesting as watching paint dry.
> 
> The fool and his money are soon departed.
> 
> The sorriest indictment is the use of this forum (advanced) for a topic of this nature. This belongs in below basic.


why mr. bruce almighty?


----------



## 14642

br85 said:


> I can't believe how many people chose option 3. This is truly a sad indictment for mobile audio.
> 
> Onto something a little different, but still on the topic of sonic fingerprint,
> recently it has come to my attention that there is the strong belief that class D amplifiers will never truly be able to replicate the class A/B because of a lack of decent *transient response*. Has anyone ever heard this effect/measured it/heard about it from anyone?
> 
> It's got me a little bit intrigued.


It's intriguing because it's a little ridiculous. Class AB amplifiers are often preferred by people because they don't sound as ugly as D when they clip. Amps clip all the time, especially little ones. It's what happens when amps clip that, in part, determines how they "sound". This is the one big fallacy in the RC challenge. His challenge requires that the amps under test remain linear--unclipped--. Nice for a challenge and one more part of the insurance against his having to give up 10 grand. 

As far as the transient thing goes, it seems like a true case of buzzwords as a substitute for an explanation. Transient response requires speed--related to frequency response and enough power to replicate the transient. This is what slew rate is supposed to indicate, but I don't think there are any modern amplifiers that can't provide their full power at the highest frequency they're rated to deliver. Even cheap garbage is able to do that. Or, this is another one of those "damping factor is important even though its effect defies physics and a scientific explanation."


----------



## MarkZ

Andy Wehmeyer said:


> It's intriguing because it's a little ridiculous. Class AB amplifiers are often preferred by people because they don't sound as ugly as D when they clip. Amps clip all the time, especially little ones. It's what happens when amps clip that, in part, determines how they "sound". This is the one big fallacy in the RC challenge. His challenge requires that the amps under test remain linear--unclipped--. Nice for a challenge and one more part of the insurance against his having to give up 10 grand.


I think that's a great point, but I'm not so sure it's a fallacy. I think his stance has been rather clear. More importantly, I think the general stance among the "nonbelievers" in audio has been to advocate the use of bigger amplifiers rather than designer amplifiers, if sonic purity is indeed the goal.


----------



## 14642

MarkZ said:


> I think that's a great point, but I'm not so sure it's a fallacy. I think his stance has been rather clear. More importantly, I think the general stance among the "nonbelievers" in audio has been to advocate the use of bigger amplifiers rather than designer amplifiers, if sonic purity is indeed the goal.


OK. I'll agree with that. My issue with the challenge is that the takeaway for many neophytes is "all amps sound the same", which is certainly not true.


----------



## stryke23x

Not sure if this was mentioned as I don't have time to read through all 15 pages. You can easily view changes in nearly anything with the Audio DiffMaker software. 

http://www.libinst.com/Audio DiffMaker.htm

It's intended to help pinpoint differences between cables, speaker wire, etc, which in most cases there is none. Properly matching levels between amps and then using the software will let you determine the difference between the amps.

John


----------



## Beat_Dominator

First off: I think there are sonic differences.

Is it POSSIBLE that maybe the audio chain, from how a recording was created and mastered, to the speakers is SO complex that we'll never solve this puzzle?

Impedance differences between speaker/amp and amp/source, as well as available dynamic headroom all play their part and will make different amps (that measure differently....since no two will ever measure the same) sound different.

Any person that tells you it doesn't matter which amp you use is either too stubborn to concede to the above statement, or deaf.


----------



## MarkZ

Beat_Dominator said:


> First off: I think there are sonic differences.
> 
> Is it POSSIBLE that maybe the audio chain, from how a recording was created and mastered, to the speakers is SO complex that we'll never solve this puzzle?


Nope. The Hafler experiments pretty much demonstrated that. But even that aside, we know enough about electricity to be able to understand that in the absence of measured electrical differences, there are no other forces at play (from an amplifier) that can influence a speaker's movement. In other words, if they measure the same, then the speaker will behave the same.

You guys gotta remember -- audio is EASY relative to other scientific questions.




> Impedance differences between speaker/amp and amp/source, as well as available dynamic headroom all play their part and will make different amps (that measure differently....since no two will ever measure the same) sound different.


These things will all yield measurable effects, though. I think what you're saying is that even the most minuscule differences can potentially be audible. That's possible. But I think we also know enough about the auditory system to be able to predict, to at least a coarse approximation, what will be audible. Perhaps more importantly, properly-controlled listening tests will tell the story.



> Any person that tells you it doesn't matter which amp you use is either too stubborn to concede to the above statement, or deaf.


Pffff. It's a long-standing debate that's far more complicated than such blanket statements. Watch the Arny Krueger John Atkinson debate if you want a glimpse of each side's contention on the matter. You're unlikely to find better debaters on either side than those two. My two cents at least.


----------



## chad

Beat_Dominator said:


> Impedance differences between speaker/amp and amp/source, as well as available dynamic headroom all play their part and will make different amps (that measure differently....since no two will ever measure the same) sound different.


For tube amplification with output transformers, yes, but we are dealing largely with SS amplifiers that have a very low and flat output impedance from DC to Daylight, unless you are trying to slip a DF argument in here 

Again, it's not a matching thing, it's very low out to very high in, unlikely AT ALL to make a difference.

Dynamic headroom..... do you mean the top of the rail voltage or LACK of sag of the power supply? Remember we are talking about an amplifier running in LINEAR mode, if the rail is sagging and allowing the amplifier to clip on tranisents... then it ain't linerar 


MarkZ said:


> Watch the Arny Krueger John Atkinson debate if you want a glimpse of each side's contention on the matter. You're unlikely to find better debaters on either side than those two. My two cents at least.


My left eye is now twitching, and I presume it won't stop for a while......


----------



## MarkZ

chad said:


> For tube amplification with output transformers, yes, but we are dealing largely with SS amplifiers that have a very low and flat output impedance from DC to Daylight, unless you are trying to slip a DF argument in here
> 
> Again, it's not a matching thing, it's very low out to very high in, unlikely AT ALL to make a difference.
> 
> Dynamic headroom..... do you mean the top of the rail voltage or LACK of sag of the power supply? Remember we are talking about an amplifier running in LINEAR mode, if the rail is sagging and allowing the amplifier to clip on tranisents... then it ain't linerar
> 
> 
> My left eye is now twitching, and I presume it won't stop for a while......


Nice color-coded post. You're revolutionizing the forum. 

I meant the actual in-person debate, by the way. Not sure if you've listened to it. I don't mean their tedious usenet jousting. Check out the captivated audience!


----------



## chad

MarkZ said:


> Nice color-coded post. You're revolutionizing the forum.
> I meant the actual in-person debate, by the way. Not sure if you've listened to it. I don't mean their tedious usenet jousting. Check out the captivated audience!


It's easier to highlight and hit a color then to re-quote the short stuff 

Is there audio of it anywhere? youtube? The audience looks like a ham convention:blush:


----------



## MarkZ

chad said:


> It's easier to highlight and hit a color then to re-quote the short stuff
> 
> Is there audio of it anywhere? youtube? The audience looks like a ham convention:blush:


There's a download link of the audio on the stereophile page.

http://www.stereophile.com/news/050905debate/

If you're having trouble sleeping at night, I highly recommend it. [The pace would make a Texan bored...] However, I think Arny does a reasonable job at characterizing the subjectivism vs. objectivism debate. And usenet gets some love.


----------



## fliplyricist1

So I guess the general concensus is that we should all save money and just invest in Jensen 4 channels? : O


----------



## Oliver

Using your ears only it is kind of hard to tell a difference, but your eyes always tell you which ones sound better  !!


----------



## Beat_Dominator

I guess I'll add, that part of what I was getting to is that we don't know EVERYTHING. (We being man kind).

This is in reference to one of the biggest hurdles affecting all fields of science. We think we have it all figured out, but we don't. 

I just think it's ENTIRELY possible that there is something that makes even the lowest signals/distortions.....not necessarily audible, but noticeable, and we just don't know what it is. Meridian just made a CD player that has a brickwall FIR filter with no pre-ripple effects in impulse response, and people SWEAR they can tell the difference, who's to say they can't? The fact of the matter is that there have just plain been too few studies on the matter.


----------



## t3sn4f2

fliplyricist1 said:


> So I guess the general concensus is that we should all save money and just invest in Jensen 4 channels? : O


*If a tree falls in the forest and there is no one around to hear it, does it make a sound?*

*No*, it makes a shock wave that travels through the air. Sound, is an human translation and interpretation of that physical phenomenon.

Do all amps that measure the same and are used within there limits _*sound*_ the same? 

No, they send the same exact shock wave through the air. How they sound is determined by the individual listening to that shock wave. 

This is why it's all in *your* head. 

What this thread embodies is to comunicated that there _is an option_ to change how you hear something through knowledge and are not tied down by the laws of nature. 

There is nothing wrong if you can't or simply choose not to look into this, which is why this debate will never end. People are trying to make it a right or wrong issue when it is really a matter of taste. 

Chocolate taste better then vanilla! No, vanilla taste better then chocolate!


----------



## MarkZ

Beat_Dominator said:


> I guess I'll add, that part of what I was getting to is that we don't know EVERYTHING. (We being man kind).
> 
> This is in reference to one of the biggest hurdles affecting all fields of science. We think we have it all figured out, but we don't.
> 
> I just think it's ENTIRELY possible that there is something that makes even the lowest signals/distortions.....not necessarily audible, but noticeable, and we just don't know what it is. Meridian just made a CD player that has a brickwall FIR filter with no pre-ripple effects in impulse response, and people SWEAR they can tell the difference, who's to say they can't? The fact of the matter is that there have just plain been too few studies on the matter.


That's why people design tests with real subjects. If they think they can tell a difference, then it's incumbent upon the scientists to design an experiment that can allow them to reliably discriminate the two pieces of equipment.


----------



## MarkZ

t3sn4f2 said:


> *If a tree falls in the forest and there is no one around to hear it, does it make a sound?*
> 
> *No*, it makes a shock wave that travels through the air. Sound, is an human translation and interpretation of that physical phenomenon.
> 
> Do all amps that measure the same and are used within there limits _*sound*_ the same?
> 
> No, they send the same exact shock wave through the air. How they sound is determined by the individual listening to that shock wave.
> 
> This is why it's all in *your* head.
> 
> What this thread embodies is to comunicated that there _is an option_ to change how you hear something through knowledge and are not tied down by the laws of nature.
> 
> There is nothing wrong if you can't or simply choose not to look into this, which is why this debate will never end. People are trying to make it a right or wrong issue when it is really a matter of taste.
> 
> Chocolate taste better then vanilla! No, vanilla taste better then chocolate!


It's not about subjective impressions. It's basically about jnd's.


----------



## t3sn4f2

Beat_Dominator said:


> I guess I'll add, that part of what I was getting to is that we don't know EVERYTHING. (We being man kind).
> 
> This is in reference to one of the biggest hurdles affecting all fields of science. We think we have it all figured out, but we don't.
> 
> I just think it's ENTIRELY possible that there is something that makes even the lowest signals/distortions.....not necessarily audible, but noticeable, and we just don't know what it is. Meridian just made a CD player that has a brickwall FIR filter with no pre-ripple effects in impulse response, and people SWEAR they can tell the difference, who's to say they can't? The fact of the matter is that there have just plain been too few studies on the matter.


Wanna bet you won't hear a difference if I put this amps guts











inside this amp












without you knowing and set the gain so no more is outputted then what the smaller amp is capable of?


----------



## DS-21

Beat_Dominator said:


> I just think it's ENTIRELY possible that there is something that makes even the lowest signals/distortions.....not necessarily audible, but noticeable, and we just don't know what it is.


How can something sonic in audio gear be "not...audbile, but noticeable?"

That sounds like a (presumably) bad recent Mike Myers movie...



t3sn4f2 said:


> Wanna bet you won't hear a difference if I put this amps guts
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> inside this amp


There, depending on the speakers, you just might. Simply because the T-amp rolls off pretty early in the bass and doesn't take to low impedances well. (Hence, all of the people saying it sounds like a "good tube amp.") However, your basic point is quite sound. Take any decent cheap amp (say, a decent receiver, one of those Behringer pro amps with RCA inputs, etc.) and put its guts in your favorite Halcro/Krell/McIntosh/Burmeister, etc., and nobody will be the wiser...


----------



## t3sn4f2

DS-21 said:


> How can something sonic in audio gear be "not...audbile, but noticeable?"
> 
> That sounds like a (presumably) bad recent Mike Myers movie...
> 
> 
> 
> There, depending on the speakers, you just might. Simply because the T-amp rolls off pretty early in the bass and doesn't take to low impedances well. (Hence, all of the people saying it sounds like a "good tube amp.") However, your basic point is quite sound. Take any decent cheap amp (say, a decent receiver, one of those Behringer pro amps with RCA inputs, etc.) and put its guts in your favorite Halcro/Krell/McIntosh/Burmeister, etc., and nobody will be the wiser...


Yeah the example was pretty extreme. Hopefully people get the picture from what you added to it.


----------



## Oliver

t3sn4f2 said:


> *If a tree falls in the forest and there is no one around to hear it, does it make a sound?*


If you are walking alone through the forest and the tree falls on you and you die, will anyone know if it made a sound ? or care ? 

Stay out of the forest


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## Beat_Dominator

DS-21 said:


> How can something sonic in audio gear be "not...audbile, but noticeable?"
> 
> That sounds like a (presumably) bad recent Mike Myers movie...


What I was trying to say is hard to put into words. I guess I meant that there can be audible differences.... but of a sort we don't realize are there, and thus have no way to describe or quantify their existance.


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## marko

i have one simple question, if a watt is a watt and all amps sound the same then why don't we all use class d amps on our mids and tweeters?


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## Oliver

marko said:


> i have one simple question, if a watt is a watt and all amps sound the same then why don't we all use class d amps on our mids and tweeters?


Alpine pdx


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## ~thematt~

marko said:


> i have one simple question, if a watt is a watt and all amps sound the same then why don't we all use class d amps on our mids and tweeters?


Ahh, the queries of someone who didnt read all the discussions. 

Noone has said that amps sound the same. They said that we (humans) cannot tell the difference between two amplifiers_ if they measure the same_...

Add to that, amplifiers SHOULD measure the same, unless someone changes something ON PURPOSE to modify the signal throughput. In theory, Amplifiers are designed as gain blocks, and therefore do not modify the signal. If they have an audible signature, they are not doing their job properly.


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## DS-21

marko said:


> i have one simple question, if a watt is a watt and all amps sound the same then why don't we all use class d amps on our mids and tweeters?


Because the industry has been rather slow in rolling them out.

I used to use a class D amp on my home mains (Panasonic XR55) and wish I still did. It was smaller and used less energy for a given output than my current receiver. It wasn't that powerful, having been measured by a German magazine as giving ~85wpc, but my mains are also 96dB/w/m efficient so a huge amount of power isn't required anyway. It used really cool technology that combined D/A conversion and amplifcation (PCM -> PWM) in a single step. And it was cheap, too! Alas, people weren't smart enough to realize that those two benefits far outweigh any alleged sonic detriments vis a vis AB amps. My current Denon receiver does sound better, but not because of its amp or its ~8x higher MSRP. The new one sounds better because it incorporates Audyssey's excellent MultEQ XT room correction software.

But I'd still pay $2000 for something based on the TI PurePath amp chips that also had a good room correction program built in.


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## DS-21

Beat_Dominator said:


> What I was trying to say is hard to put into words.


You may be finding it difficult to put this idea into words, but that's solely because it is utter nonsense.

If something is audible, there's one way (and _only_ one way) to find out: subjective controlled same/different double-blind auditions, often short-handed as "ABX tests." The only measurement instrument for such tests (once levels have been properly matched, at least) is the ears of critical listeners. Anything that can't be heard - i.e. the "differences" in amps, digital sources, wires, and so on that are often trumpeted in the purplest of prose by an audio press reliant on advertising from makers of those things - _is simply not there to be heard!_ 

If solely through listening one doesn't hear something as being consistently different from something else, then the functioning human mind draws the logical conclusion that the two things are effectively not different. The lesser mind tries to find a way to discredit any listening experience that doesn't provide the listener of the pathetic crutch of knowing exactly what s/he is listening to when determining its alleged sonic properties. Now, that's not to say there aren't a multitude of perfectly reasonable subjective reasons to prefer one piece of kit over another. But they are usually not related to fidelity to the source material, rather some aesthetic, ergonomic, snob appeal, or perceived/actual build quality issue.


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## t3sn4f2

DS-21 said:


> Because the industry has been rather slow in rolling them out.
> 
> I used to use a class D amp on my home mains (Panasonic XR55) and wish I still did. It was smaller and used less energy for a given output than my current receiver. It wasn't that powerful, having been measured by a German magazine as giving ~85wpc, but my mains are also 96dB/w/m efficient so a huge amount of power isn't required anyway. It used really cool technology that combined D/A conversion and amplifcation (PCM -> PWM) in a single step. And it was cheap, too! Alas, people weren't smart enough to realize that those two benefits far outweigh any alleged sonic detriments vis a vis AB amps. My current Denon receiver does sound better, but not because of its amp or its ~8x higher MSRP. The new one sounds better because it incorporates Audyssey's excellent MultEQ XT room correction software.
> 
> But I'd still pay $2000 for something based on the TI PurePath amp chips that also had a good room correction program built in.


That sure is a bad ass receiver. I like the increased power bi-amp option a lot, it's like an A+B on a regular receiver but its takes power from the other channel to essentially double not divide the power. 

Right now I have a regular receiver on A+B bi-amping Infinity 3-ways and I notice a definite lack of mid bass distortion harmonics on the highs thanks to the isolated highs channel. Less power for loud transient notes (which I probably could note notice if they distort or not) but over all better quality at decent output.

Or at least I got a false impression and the channels aren't really isolated in that way leaving the improvement all in my head


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## Beat_Dominator

DS-21 said:


> You may be finding it difficult to put this idea into words, but that's solely because it is utter nonsense.
> 
> If something is audible, there's one way (and _only_ one way) to find out: subjective controlled same/different double-blind auditions, often short-handed as "ABX tests." The only measurement instrument for such tests (once levels have been properly matched, at least) is the ears of critical listeners. Anything that can't be heard - i.e. the "differences" in amps, digital sources, wires, and so on that are often trumpeted in the purplest of prose by an audio press reliant on advertising from makers of those things - _is simply not there to be heard!_
> 
> If solely through listening one doesn't hear something as being consistently different from something else, then the functioning human mind draws the logical conclusion that the two things are effectively not different. The lesser mind tries to find a way to discredit any listening experience that doesn't provide the listener of the pathetic crutch of knowing exactly what s/he is listening to when determining its alleged sonic properties. Now, that's not to say there aren't a multitude of perfectly reasonable subjective reasons to prefer one piece of kit over another. But they are usually not related to fidelity to the source material, rather some aesthetic, ergonomic, snob appeal, or perceived/actual build quality issue.



Like I said it's hard to put into words. Your response completely misses the point I was trying to make


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## Mooble

It still amazes me how long this stupid argument goes on. It's the nature of the argument to which I object the most. It's not a technical fallacy, but a logical one.

Clearly, all amps do not sound the same. This is obvious. If you want a little low range boost, you buy an old RF The Punch amp. Was it a manipulated signal? Of course! The people who bought it thought it sounded better. Amps have all kinds of gimmicks built into them to make them audibly more pleasing to some. That is often what you are paying for in a more expensive amp. If you negate those factors, you are negating the very reason for purchasing that amp. 

Just how far are you willing to go to make one amp sound like another? How much are you willing to disable? Are you willing to rip out half the circuits of a Zapco DC Reference to make it sound like a Cuspid? What's the point? The reason you are buying a DC Reference is to get the processing power. I'm sure you could spend 20 hours completely ripping the guts out of an amp and resoldering everything to make it sound like another, but then you no longer have a DC Reference, you have a completely new bastardized amp. That is as stupid as me ripping the drivetrain and suspension out of a Bentley and putting in a Taurus drivetrain and saying, "see, with enough work I can prove that a Bentley and a Taurus drive the same."

RC's argument loses all logical credibility when we start talking about altering amps to make them measure the same. The fact is that no two amps measure the same, not even the same model.


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## t3sn4f2

Beat_Dominator said:


> Like I said it's hard to put into words. Your response completely misses the point I was trying to make


You mean something like this? 

http://jn.physiology.org/cgi/content/abstract/83/6/3548


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## rhinodog00

Add to that, amplifiers SHOULD measure the same, unless someone changes something ON PURPOSE to modify the signal throughput. In theory, Amplifiers are designed as gain blocks, and therefore do not modify the signal. If they have an audible signature, they are not doing their job properly.[/QUOTE]

90% of amplifiers with built in processing,crossovers,bass boost etc do just that. Modify the signal. Very few pure amplifiers out there any more. This really is a loosing battle on both sides. I am curious to know what all of you who say"a watt is a watt" are using for amplifiers both at home and in the car? If we are talking about low listening levels,which seems to be the reccuring theme, then I would agree that they would sound the same. As would most component speaker sets. When amps are pushed hard I would say that there deffinitely are differences in the way they sound. Just my opinion. I am no expert. Just going off of my own personal experience. If low listening levels are what you are into save your money and keep your factory system.


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## MarkZ

Mooble said:


> It still amazes me how long this stupid argument goes on. It's the nature of the argument to which I object the most. It's not a technical fallacy, but a logical one.
> 
> Clearly, all amps do not sound the same. This is obvious. If you want a little low range boost, you buy an old RF The Punch amp. Was it a manipulated signal? Of course! The people who bought it thought it sounded better. Amps have all kinds of gimmicks built into them to make them audibly more pleasing to some. That is often what you are paying for in a more expensive amp. If you negate those factors, you are negating the very reason for purchasing that amp.
> 
> Just how far are you willing to go to make one amp sound like another? How much are you willing to disable? Are you willing to rip out half the circuits of a Zapco DC Reference to make it sound like a Cuspid? What's the point? The reason you are buying a DC Reference is to get the processing power. I'm sure you could spend 20 hours completely ripping the guts out of an amp and resoldering everything to make it sound like another, but then you no longer have a DC Reference, you have a completely new bastardized amp. That is as stupid as me ripping the drivetrain and suspension out of a Bentley and putting in a Taurus drivetrain and saying, "see, with enough work I can prove that a Bentley and a Taurus drive the same."
> 
> RC's argument loses all logical credibility when we start talking about altering amps to make them measure the same. The fact is that no two amps measure the same, not even the same model.


I don't think it's a logical fallacy. I think you're simply missing the point of the debate. I don't think anyone has ever made the claim that amps with different signal processors built in will sound the same. The claim, as it has always been for decades, is that the amplifier itself (not the frills) contributes to the sound in a way that can be perceived from another.

The frills simply get in the way of the true debate. And that's why they need to be disabled in order to isolate the true variables, not extraneous "features".

It's also why the condition that the amps are not clipping is required. The "amps that measure the same sound the same" crowd usually describes any perceived differences as coming from clipping -- the subjectivists' claim has been that the differences appear even within the amp's linear range.

That is what's being tested.


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## MarkZ

t3sn4f2 said:


> You mean something like this?
> 
> http://jn.physiology.org/cgi/content/abstract/83/6/3548


Actually, that still doesn't make his point. Note the following line towards the end of the abstract: "Psychological evaluation indicated that the subjects felt the sound containing an HFC to be more pleasant than the same sound lacking an HFC."

In other words, the effect is audible.

What the authors are calling "inaudible" is really a characterization of a signal that's inaudible when presented by itself, but audible when presented in conjunction with other sounds.

That's entirely consistent with DS-21's stance that the best way to determine such things is through ABX testing (which I'm sure is reasonably close to how the authors of that article performed the "psychological evaluation").


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## MarkZ

rhinodog00 said:


> 90% of amplifiers with built in processing,crossovers,bass boost etc do just that. Modify the signal. Very few pure amplifiers out there any more. This really is a loosing battle on both sides. I am curious to know what all of you who say"a watt is a watt" are using for amplifiers both at home and in the car?


I use two 10 year old amplifiers (ESX), because I'm too cheap to buy something new that would offer that kind of reliability. My third amplifier is for the sub (used Zed Minilith), which was about the cheapest class D amp I could find in that power range that also was built by someone with a reputation for reliability and customer service.

At no point did I ever consider the "sonic characteristics" of the amp in my purchase.



> If we are talking about low listening levels,which seems to be the reccuring theme, then I would agree that they would sound the same. As would most component speaker sets. When amps are pushed hard I would say that there deffinitely are differences in the way they sound. Just my opinion. I am no expert. Just going off of my own personal experience. If low listening levels are what you are into save your money and keep your factory system.


I think you're right about pushing amps hard. When you drive them into clipping, funny things can happen -- the distortion "signature" it may produce might be different from another amp; it may go into protection; it may even die.

But what's the proposed solution to that? Buying a designer amplifier at 2x the cost? Or doubling (or tripling) your wattage for 2x the cost? I'd argue that the latter is the better option.


----------



## Mooble

MarkZ said:


> I don't think it's a logical fallacy. I think you're simply missing the point of the debate. I don't think anyone has ever made the claim that amps with different signal processors built in will sound the same. The claim, as it has always been for decades, is that the amplifier itself (not the frills) contributes to the sound in a way that can be perceived from another.
> 
> The frills simply get in the way of the true debate. And that's why they need to be disabled in order to isolate the true variables, not extraneous "features".
> 
> It's also why the condition that the amps are not clipping is required. The "amps that measure the same sound the same" crowd usually describes any perceived differences as coming from clipping -- the subjectivists' claim has been that the differences appear even within the amp's linear range.
> 
> That is what's being tested.


RC's argument is to disprove the elitists who say that a $10,000 amp will sound better than a $200 amp, but you will never find two comparable amps to test his argument. Basically you need two identical amps except that one uses boutique parts, and one uses cheapo parts. You would need to build these amps yourself to test this.

He is trying to prove that spending money on expensive amps is useless as far as SQ is concerned, but as I mentioned, sometimes you are paying for that extra *whatever* and to disable that or filter it out, negates the whole reason you bought the more expensive amp. 

His intention is sound, but the challenge is a joke. Once you start disabling or filtering out anything, you no longer have a stock amp. How far can you go with that rationale? Can I whack a Sinfoni with a hammer and prove that it sounds worse than a Cadence?


----------



## rhinodog00

MarkZ said:


> I don't think it's a logical fallacy. I think you're simply missing the point of the debate. I don't think anyone has ever made the claim that amps with different signal processors built in will sound the same. The claim, as it has always been for decades, is that the amplifier itself (not the frills) contributes to the sound in a way that can be perceived from another.
> 
> The frills simply get in the way of the true debate. And that's why they need to be disabled in order to isolate the true variables, not extraneous "features".
> 
> It's also why the condition that the amps are not clipping is required. The "amps that measure the same sound the same" crowd usually describes any perceived differences as coming from clipping -- the subjectivists' claim has been that the differences appear even within the amp's linear range.
> 
> That is what's being tested.


That makes a lot more sense than just stating that "a watt is a watt". Reading through your post makes me realize that almost all amplifiers would indeed sound different. Almost all amplifiers these days for car use have some type of built in crossover,processing,bass boost etc. that even when disabled still affects the sonics of the amp. I would agree that if you could find 2 amps ,that measured exactly the same and clipped at the same volume and had no processing what so ever, would sound the same. Am I wrong?


----------



## MarkZ

rhinodog00 said:


> I would agree that if you could find 2 amps ,that measured exactly the same and clipped at the same volume and had no processing what so ever, would sound the same. Am I wrong?


That's what we, the "watt is a watt" crowd, say. But there are lots and lots of people out there who think that if they measure the same they can still sound different -- hence the poll results.


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## rhinodog00

MarkZ said:


> That's what we, the "watt is a watt" crowd, say. But there are lots and lots of people out there who think that if they measure the same they can still sound different -- hence the poll results.


I get it now. Thanks for taking the time to explain rather than just hammer your opinion. The fact is ,after all this, is that you would be very hard pressed to find those 2 magical amps that have the exact same measurements. Unless it is the same amp. In which case I am %100 sure that it would sound the same.


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## Beat_Dominator

t3sn4f2 said:


> You mean something like this?
> 
> http://jn.physiology.org/cgi/content/abstract/83/6/3548


That is more along the lines of what I'm thinking, only I believe there can be more cases like this where no one has identified the piece that would need testing. 

I can see what MarkZ is saying...that it "must" be audible, but if we have not yet identified or perceived this factor, we're still "blind" to it....sonically speaking 

I guess my argument boils down to the fact that the Human brain is amazingly complex and capable of drawing conclusions for us, using data we have no idea exists. Couple this with biological differences (some people CAN hear better than others, some people have sensory integration disorders that could easily hinder or benefit their auditory system) and you get an argument no one can win.


----------



## Mooble

I still think my Bentley / Taurus argument is a good one. Could I do enough things to a Bentley to make it drive like a Taurus? Yes! I could. Ok, *so what*? The guy who buys a Bentley wants those special things that make it a Bentley, so what have you proven? Have you convinced that Bentley owner that he doesn't need to be able to drive 190 mph just because a Taurus can't go that fast?

Clipping is basically the same thing as driving a Taurus and a Bentley at the ragged edge. RC won't allow clipping. Why? Because then you can hear audible differences between amps. Well, what if I wanted an amp that I could drive to the ragged edge? Then this argument is useless, isn't it? What if I want an amp that is stable with 1/4 ohm load? Not all amps can do that either, so again, the RC challenge can't help me.

Let me propose the only realistic use of RC's argument:

Here I am trying to decide between magical amp 1 and magical amp 2. Both of them are identical in every way except that one uses solid gold parts and costs $3,500 and the other one uses off the shelf parts and costs $300. I don't care about anything but how they sound. Great! With RC's argument I now know which amp to buy. All of this discussion revolves around a situation that will never happen in the real world. So again, what's the point?

Amps are bought for a number of different reasons all of which he mentions: build quality, cooling, low impedance loads, reliability, clipping, etc. He tackles only one of them, albeit a very important one, sound quality.

SO WHAT IS THE POINT OF THIS ARGUMENT??? There are a dozen different reasons why people buy amps and some, like clipping, also involve sound quality. The scope of this argument is so narrow as to render it useless in any real world application.


----------



## MarkZ

Beat_Dominator said:


> That is more along the lines of what I'm thinking, only I believe there can be more cases like this where no one has identified the piece that would need testing.
> 
> I can see what MarkZ is saying...that it "must" be audible, but if we have not yet identified or perceived this factor, we're still "blind" to it....sonically speaking


No, by its very definition, we're not blind to it. If you perform the experiment that DS-21 mentioned, you can distinguish whether or not there are perceptual differences.

In other words, if you're "blind" to it but it still elicits some sort of percept...then you can't be blind to it. There's no gray area here (except for the gray area that exists where you're at the cusp of threshold).




> I guess my argument boils down to the fact that the Human brain is amazingly complex and capable of drawing conclusions for us, using data we have no idea exists. Couple this with biological differences (some people CAN hear better than others, some people have sensory integration disorders that could easily hinder or benefit their auditory system) and you get an argument no one can win.


I think you're overcomplicating things. You're right that there are a lot of questions about how the brain manages to do these things, but if you can detect a difference then by definition you're not "blind" to it.


----------



## dtviewer

Mooble said:


> ---snipped-----
> SO WHAT IS THE POINT OF THIS ARGUMENT??? There are a dozen different reasons why people buy amps and some, like clipping, also involve sound quality.


The point of his argument is that within their intended operating parameters, two amps matched to the same volume will sound the same.
Its that simple.

All the talk about Amp A's 'velvety, liquid midrange' and Amp B's 'excepional rhythim and pace' is a bunch of crap fueled by marketing hype.

His experiment/challenge was setup to prove just that and it does so very well.


----------



## squeak9798

I think half of the issues with this discussion stem from a fundamental misunderstanding of what it is exactly that is being argued, and when the "RC challenge" gets thrown in we can add a fundamental misunderstanding of the challenge itself.

First and foremost, the challenge is *not* designed to test differences between _amplifiers_. This can be seen quite clearly from the rules of the challenge. What is the point of the challenge? To identify what differences contribute to the audible signature of an amplifier, and at what level these differences occur. The challenge states nothing more than this; The measurements of power, gain, distortion, noise and frequency response completely characterize the "sonic characteristic" of a power amplifier. 

It does NOT set out to prove "all amplifiers sound the same". It sets out to prove that if you hear a difference, it can be attributed to one of the above five measurements. 



Mooble said:


> RC's argument is to disprove the elitists who say that a $10,000 amp will sound better than a $200 amp, but you will never find two comparable amps to test his argument. Basically you need two identical amps except that one uses boutique parts, and one uses cheapo parts. You would need to build these amps yourself to test this.


This statement is just silly. You do *not* need two identical amplifiers to test the hypothesis set forth in the challenge, which is that the measurements of power, gain, distortion, noise and frequency response completely characterize the "sonic characteristic" of an amplifier.

All you need is two amplifiers with measurements of power, gain, noise, distortion and frequency response that are within the variance limitations of the challenge.



> He is trying to prove that spending money on expensive amps is useless as far as SQ is concerned, but as I mentioned, sometimes you are paying for that extra *whatever* and to disable that or filter it out, negates the whole reason you bought the more expensive amp.


Again, fundamental misunderstanding of the challenge.

He's not saying higher priced amplifiers have no value. He is saying don't buy them for their fancy, high-dollar caps or other magic pixie dust. Buy them for their warranty, customer service, features, build quality, aesthetics, or prestige. But DON'T buy them for magic pixie dust.

If you want to buy a Zapco DC because of the extensive internal processing....go for it. Buy it for the processing. Buy it for the build quality, customer service, features, aesthetics and/or prestige. But don't buy it because of the type of capacitor/etc the amplifier uses. Don't buy it because you think there is an immeasurable, unquantifiable "sonic attribute" to the amplifier.



> His intention is sound, but the challenge is a joke.


The challenge is only viewed as a joke if you don't understand it 



> Once you start disabling or filtering out anything, you no longer have a stock amp.


See above. He's not testing the hypothesis at the amplifier level. He's testing it at the measurement/audibility level. 




> Can I whack a Sinfoni with a hammer and prove that it sounds worse than a Cadence?


The hammer is irrelevant.

If the gain, distortion, noise, power and frequency response are within inaudible tolerances between a Sinfoni and a Cadence, will you hear a difference? *THAT* is the point of the challenge


----------



## squeak9798

Mooble said:


> I still think my Bentley / Taurus argument is a good one. Could I do enough things to a Bentley to make it drive like a Taurus? Yes! I could. Ok, *so what*? The guy who buys a Bentley wants those special things that make it a Bentley, so what have you proven? Have you convinced that Bentley owner that he doesn't need to be able to drive 190 mph just because a Taurus can't go that fast?


Actually, a more appropriate statement would be that if you want to drive 190mph, don't buy the Bentley because it has more expensive paint  The more expensive paint looks great, but it doesn't help you go 190mph. That is, unless _you want_ to spend all of that extra money for the _prestige_ of owning a car with more expensive paint. Just don't cite the paint as the reason a Bentley can go 190mph.





> Clipping is basically the same thing as driving a Taurus and a Bentley at the ragged edge. RC won't allow clipping. Why? Because then you can hear audible differences between amps.


Exactly! We *KNOW* the levels of distortion involved when clipping can cause audible differences. We KNOW it's related to the distortion/etc while clipping. So this is of complete non-interest to his challenge. He is NOT testing to see what form of clipping you find _most pleasing_ 



> Well, what if I wanted an amp that I could drive to the ragged edge? Then this argument is useless, isn't it?


Not entirely.

But as was mentioned by Mark earlier.....is the best method of remedying your issue of clipping to spend big bucks on an amp that clips how you prefer, or to spend the money (pontentially _less money_) on a higher-powered amp to reduce the amount of clipping that occurs? Most people would say the latter. And this is where the challenge helps us, by realizing the potential differences between the options and amplifiers.





> What if I want an amp that is stable with 1/4 ohm load? Not all amps can do that either, so again, the RC challenge can't help me.


Correct. That falls under find the amp with the features you desire. 

Moot point to the discussion. 





> All of this discussion revolves around a situation that will never happen in the real world. So again, what's the point?




You don't find it useful in real world applications to know that the only differences that contribute to the sonics of an amplifier are power, gain, distortion, noise and frequency response? I think this is immensely important information to be armed with. That $1k amp sounds great, much better than the $300 amp. But I wonder why? Maybe it's a simple frequency response variation at 1khz - 2khz? We do some research and find out that's exactly the reason! So now I can buy the $300 amp, make a few EQ adjustments and have the exact same sound as the $1k provided that I liked so much!



> Amps are bought for a number of different reasons all of which he mentions: build quality, cooling, low impedance loads, reliability, clipping, etc. He tackles only one of them, albeit a very important one, sound quality.
> 
> SO WHAT IS THE POINT OF THIS ARGUMENT??? There are a dozen different reasons why people buy amps and some, like clipping, also involve sound quality. The scope of this argument is so narrow as to render it useless in any real world application.


Again, I don't think you fully understand the challenge.


----------



## Mooble

dtviewer said:


> All the talk about Amp A's 'velvety, liquid midrange' and Amp B's 'excepional rhythim and pace' is a bunch of crap fueled by marketing hype.



Yes, that is the *ONLY* thing that it proves-that there is no pixie dust. Don't get me wrong, there are people who believe in pixie dust, but let's get beyond pixie dust.

RC is not saying that all amps sound alike, but he is saying that if you take out all of the REAL differences between amps, that they will be indistinguishable. Ok, so what? There are differences in amps and people choose amps based on those differences.

If I buy amp A because it artificially manipulates the signal with hidden EQ that translates into "velvety midrange," it will still sound better than amp B that doesn't have it--to me. Do I care that amp A will sound like amp B if I remove the EQing? No. I bought amp A because I liked that sound. So what good is this argument? (By the way this is not me, I prefer an amp with nothing but a gain control personally)


----------



## MarkZ

Mooble said:


> I still think my Bentley / Taurus argument is a good one. Could I do enough things to a Bentley to make it drive like a Taurus? Yes! I could. Ok, *so what*? The guy who buys a Bentley wanted those special things that make it a Bentley, so what have you proven? Have you convinced that Bentley owner that he doesn't need to be able to drive 190 mph just because a Taurus can't go that fast?


No, but if the Bentley's only better than the Taurus because it has seat warmers, a luxurious interior, and GPS, then it makes no sense to say that the Bentley drives better than the Taurus.

And that's what the debate is essentially about -- whether two amplifiers that measure the same sound the same. And taken further, whether two particular amplifiers in car audio sound the same.

Note that I'm saying *amplifiers* here. The crossover and EQ controls inside the same chassis that the amplifier resides does not make it an amplifier. You wouldn't take a boombox and say that the amplifier in one is better than the other because the tuner is more sensitive, or the EQ has 9 bands instead of 5.




> Clipping is basically the same thing as driving a Taurus and a Bentley at the ragged edge. RC won't allow clipping. Why? Because then you can hear audible differences between amps. Well, what if I wanted an amp that I could drive to the ragged edge? Then this argument is useless, isn't it? What if I want an amp that is stable with 1/4 ohm load? Not all amps can do that either so again, the RC challenge can't help me.


I don't think you've been around many subjectivists then. I think you're assuming that the amps will sound the same if they're not driven into clipping. Lots of people would disagree with you.


----------



## MarkZ

Mooble said:


> Yes, that is the *ONLY* thing that it proves-that there is no pixie dust. Don't get me wrong, there are people who believe in pixie dust, but let's get beyond pixie dust.
> 
> RC is not saying that all amps sound alike, but he is saying that if you take out all of the REAL differences between amps, that they will be indistinguishable. Ok, so what? There are differences in amps and people choose amps based on those differences.


You just answered your own question. It's because there are lots of people (probably the majority of those who purchase audio equipment) who DO believe in the "pixie dust". You don't think it's important to demonstrate to the majority that there's no pixie dust?


----------



## Mooble

squeak9798 said:


> Actually, a more appropriate statement would be that if you want to drive 190mph, don't buy the Bentley because it has more expensive paint  The more expensive paint looks great, but it doesn't help you go 190mph. That is, unless _you want_ to spend all of that extra money for the _prestige_ of owning a car with more expensive paint. Just don't cite the paint as the reason a Bentley can go 190mph.


BTW, I like this discussion. No hard feelings. 

To me, the above statement is what I don't like about the RC "mentality". People want to dismiss amp A as nothing more than pretty polished heatsink and gold plated terminals, even when the power supply is able to produce 3x more current than the amp is rated to handle, etc. There are plenty of reasons to pay more for an amp and they are not just silly status symbols.

There are infinite variables that make a Bentley a better car and it's much more than just an attitude or paint job, or prestige. If all you want to do is get from one place to another, then a Taurus is fine, but some people value the ability to drive 190 mph and stop on a dime. I want an amp that can do more than I ever ask of it. Maybe it won't sound any better at 1/2 output, but when put to the test, it will blow the cheaper amp away.


----------



## MarkZ

Mooble said:


> There are infinite variables that make a Bentley a better car and it's much more than just an attitude or paint job, or prestige. If all you want to do is get from one place to another, then a Taurus is fine, but some people value the ability to drive 190 mph and stop on a dime. I want an amp that can do more than I ever ask of it. Maybe it won't sound any better at 1/2 output, but when put to the test, it will blow the cheaper amp away.


Yet a cheap amp that's rated for 1000 watts will still do better than the 25x2 McIntosh when driven hard. But most people probably don't realize that.


----------



## Mooble

MarkZ said:


> Yet a cheap amp that's rated for 1000 watts will still do better than the 25x2 McIntosh when driven hard. But most people probably don't realize that.


On that I will agree, but the cheap amp doesn't have pretty blue wattage meters! 

I'm all for dismissing pixie dust, but I want to make sure real differences don't get tossed out with the pixie dust myth.


----------



## dtviewer

Mooble said:


> To me, the above statement is what I don't like about the RC "mentality". People want to dismiss amp A as nothing more than pretty polished heatsink and gold plated terminals, even when the power supply is able to produce 3x more current than the amp is rated to handle, etc. There are plenty of reasons to pay more for an amp and they are not just silly status symbols.
> .


Ahhh, the "RC Mentality". 

What exactly would that be?

As has been pointed out a couple times here before, too many people look at the amp challenge and misunderstand what RC (and others before him) are trying to teach.


Do you know that 'RC' owns many very expensive amps?


----------



## Mooble

dtviewer said:


> As has been pointed out a couple times here before, too many people look at the amp challenge and misunderstand what RC (and others before him) are trying to teach.


There is nothing difficult to understand about his challenge or its purpose. I have certainly not said that he claims all amps sound alike. I am saying that, by the time you strip away everything that you typically pay for in the more expensive amp, you don't have much of a challenge left. You basically have a cheap amp and one that is rendered cheap by removing everything that it does better than the cheap amp from the challenge (clipping, balanced inputs, low impedance loads, possible EQing, sturdier construction, better isolation, etc.)


----------



## dtviewer

Mooble said:


> There is nothing difficult to understand about his challenge or its purpose. I have certainly not said that he claims all amps sound alike. I am saying that, by the time you strip away everything that you typically pay for in the more expensive amp, you don't have much of a challenge left. You basically have a cheap amp and one that is rendered cheap by removing everything that it does better than the cheap amp from the challenge (clipping, balanced inputs, low impedance loads, possible EQing, sturdier construction, better isolation, etc.)


Mooble, not trying to be an ass, but what are you talking about?

Who has ever said anything about stripping things away? The amps in the challenge will have their gain matched. That is all in 99% of all amps used. The challenge has nothing to do with isolation, inputs, construction, nothing.

I think you are having a hard time understanding the basics of the challenge. 

Please go back and read MarkZ's and Squeaks posts.


----------



## squeak9798

Mooble said:


> There is nothing difficult to understand about his challenge or its purpose. I have certainly not said that he claims all amps sound alike. I am saying that, by the time you strip away everything that you typically pay for in the more expensive amp, you don't have much of a challenge left. You basically have a cheap amp and one that is rendered cheap by removing everything that it does better than the cheap amp from the challenge (clipping, balanced inputs, low impedance loads, possible EQing, sturdier construction, better isolation, etc.)


My issue here is that you make it sound as if RC's amp challenge is telling people there's absolutely no reason to purchase a moderately to high priced amplifier, and that the amp challenge is somehow "flawed" because he doesn't take things like build quality or features into account  None of which is true, and he doesn't "strip" anything away.

He, or most of those who hold the same general view, say nothing of the sort. We are saying that there are reasons to purchase a moderate to high priced amplifier, and there are reasons NOT to pay the extra premium for that amplifier. Buy based on your abilities and needs, not mysticism and pixie dust.

Go purchase a big buck amplifier if it has the features and power that you desire and you are willing and able to pay for it. Maybe you want to buy a McIntosh because you want an amplifier that will last you 25+ years, it has the power and features you want/need, and you thoroughly enjoy the customer service provided my McIntosh. _There's nothing wrong with this_. 

Me personally, I'll search for the most cost effective manor in which I can achieve my goals. 

There is little a big buck amplifier can do for me that would benefit me in any way. I run enough power clipping isn't a concern. I don't need balanced inputs (which is also found lower priced amps, BTW). I don't need the ability to run lower than typical loads (which is also found lower priced amps, BTW). I run external EQ/etc, so I don't need it built into the amp (which is also found lower priced amps, BTW). And most common amps have adequate enough build quality for my needs.


----------



## MarkZ

In defense of Mooble, I think he's referring to stripping away the processing and other such features (which can include actually disabling the circuits if they're not defeatable).


----------



## Mooble

dtviewer said:


> Mooble, not trying to be an ass, but what are you talking about?
> 
> Who has ever said anything about stripping things away? The amps in the challenge will have their gain matched. That is all in 99% of all amps used. The challenge has nothing to do with isolation, inputs, construction, nothing.
> 
> I think you are having a hard time understanding the basics of the challenge.
> 
> Please go back and read MarkZ's and Squeaks posts.


Rule #4, *That neither amp is loaded beyond its rated impedance.* This is certainly "fair" because you don't want to overload one amp, but it does limit the amps you can test in the challenge because they must handle equal loads. What if I have low impedance speakers? All I'm saying is that this is a limiting factor. 

Rule #5 *That all amplifiers with signal processors have those features turned off.* This is reasonable of course, but what if you bought that amp because it had an artificual warmth? It's not pixie dust, it's EQing. I don't like it, but someone else might. If you take that away, you are taking away one of the reasons the person bought that amp in the first place.

Rule #6. *That neither amp exhibits excessive noise (including RFI).* Ok, once again this is "fair," but some amps offer better isolation and noise suppression than others, especially in a car environment. Suppose amp A is noisy because it's a cheaper design and mounted next to a power source, but amp B is dead quiet in the same location because it has balanced inputs and better noise rejection through design? You take away amp B's advantage by removing that extra challenge.

Rule #7 *That each amp can be properly driven by the test setup.* This is basically the same as Rule #4, but what about current? Maybe one amp can't handle changes in voltage well. You negate the better amp's ability to shine with voltage irregularities.

Rule # 11 *That the channel separation of all amps in the test is at least 30 dB from 20Hz to 20kHz.* With headphones? Will he allow a test of one amp with 30dB separation and one with 85 dB separation?

I'm not trying to be an ass either.  What I'm saying is that many of these rules go so far to level the playing field in a clinical setting that they lose sight of real world differences that can affect sound. RC's challenge has much more use in a lab than it does in a real world environment where amp differences can be much more profound. That is where I have the problem.

One final note, this shouldn't be about price. There are some very good bargain amps out there and some ****ty expensive ones.


----------



## DS-21

Mooble said:


> Are you willing to rip out half the circuits of a Zapco DC Reference to make it sound like a Cuspid? What's the point? The reason you are buying a DC Reference is to get the processing power.


Actually, I've come around to the thought that someone buys a Zapco DC Reference amp because s/he has money but low self-esteem, so a lowly amp reseller taking the default position that s/he is an imbecile and unworthy of moving sliders on a GUI to use the overpriced piece of kit s/he just bought is A-OK....



rhinodog00 said:


> The fact is ,after all this, is that you would be very hard pressed to find those 2 magical amps that have the exact same measurements. Unless it is the same amp. In which case I am %100 sure that it would sound the same.


Amps hardly need "the exact same measurements" to sound exactly the same. They just need to be reasonably competent in design.



Mooble said:


> I still think my Bentley / Taurus argument is a good one. Could I do enough things to a Bentley to make it drive like a Taurus?


You're basically making a snob-appeal argument here, but the analogy does not hold.

The biggest difference there is that people looking at it will see that one's a Taurus and one's a Bentley. Everyone will know the difference because it's all out there, and everybody knows a little bit about cars. By contrast, how many people have seen your car amp installed? How many people know anything about it, except that it makes the music go when you flip the ignition? And frankly, most people would be more impressed by something that says "Sony" than something that says "McIntosh" or "JL Audio" on it, simply because most people aren't that interested in audio. So except in very small circles, there really isn't snob appeal to expensive amps. (Even less so than in home audio, where at least many people keep their gear front-and-center in a room. So choosing a boutique part that doesn't sound any different from much cheaper and possibly better-built mass market part can be thought of as an aesthetic choice in home audio, but not really in car-fi.) And unlike other expensive products where there are clear differences to the user, there just isn't one in amps.



Mooble said:


> Well, what if I wanted an amp that I could drive to the ragged edge? Then this argument is useless, isn't it? What if I want an amp that is stable with 1/4 ohm load? Not all amps can do that either, so again, the RC challenge can't help me.


The RC challenge isn't the point. Simple human reality is. If you need an amp that can put out a certain level of dBW, buy one that can do it. If you need one stable to a given impedance, make sure it is designed for that. But any amp meeting those two qualifications will be sonically identical, assuming competent design.



Mooble said:


> If I buy amp A because it artificially manipulates the signal with hidden EQ that translates into "velvety midrange," it will still sound better than amp B that doesn't have it--to me.


First, I think that circumstance is pretty rare. I can only think of one amp that I've experienced that was designed to be non-flat: the Butler Tube Driver, which had large amounts of midrange EQ to start with and had a "tube sound" knob that just increased the midrange boost. Sure, others have defeatable tone controls, signal processing, and crossover functions, some of which may be useful and even the reason one picks amp A over amp B, but that's entirely separate from the innate sound quality of the amplification part.

Second, one could also measure the difference between the two, and incorporate that into your "house curve" using Amp B, assuming of course that it's a standard rather than a designer model. If one's not using signal processing capable of such feats, one is not really serious about getting good sound anyway, so why even bother with expensive amps unless one just has a fetish for pricey baubles?


----------



## squeak9798

Mooble, I think you are, for whatever reason, taking the amp challenge and claiming it's trying to act as an all-inclusive guide to amplifier purchases. It is nothing of the sort. You are continually raise issues which have *ZERO* to do with the challenge itself or the results of the challenge. Does it set a bar for what differences are audible with music? Yes, it does a pretty good job of that. Does it act as a purchasing guide, telling you what features you need and/or should use? No, it does not. Don't use it or portray it as such.



Mooble said:


> Rule #4, *That neither amp is loaded beyond its rated impedance.* This is certainly "fair" because you don't want to overload one amp, but it does limit the amps you can test in the challenge because they must handle equal loads. What if I have low impedance speakers? All I'm saying is that this is a limiting factor.


The issue you raise is *completely irrelevant* to the challenge. There will ALWAYS be a load that each amplifier can mutually handle. 4ohm or 8ohm would be great examples of such a loads  This in no way limits the amplifiers that can be used in the challenge. There may be, however, a limit to which amplifiers fit_ your needs_. 

Why would you even want to compare two amplifiers, if one of them does not fit your needs? If I had a 2ohm stereo load, would I waste my time looking at an amplifier that can not handle said load, or complaining that I can't compare it against an amplifier that can handle the load? The issue you raise sounds _much less_ "real world" than the rule stated in the amp challenge. 



> Rule #5 *That all amplifiers with signal processors have those features turned off.* This is reasonable of course, but what if you bought that amp because it had an artificual warmth? It's not pixie dust, it's EQing. I don't like it, but someone else might. If you take that away, you are taking away one of the reasons the person bought that amp in the first place.


The issue you raise is *completely irrelevant* to the challenge. 

Again, the challenge is *not* designed to determine your preferences for frequency response. It is *not* an amplifier purchase guide.

Also, if one amplifier does have an inherent frequency response anomaly an EQ can be placed in the chain of EITHER amplifier, at the _test-takers_ discretion. So you can chose to either EQ out the anomaly, or EQ _in_ the same anomaly into the other amplifier. But again, this is only to "level the playing field", NOT to assist you in determining what frequency response you best prefer. 

Lastly, if you know that the reason you like the amp is for it's frequency response, and the amp is rather expensive.....it may be more cost effective to purchase a less expensive amplifier and an EQ and EQ in the response you are looking for  A benefit of understanding the amp challenge.



> Rule #6. *That neither amp exhibits excessive noise (including RFI).* Ok, once again this is "fair," but some amps offer better isolation and noise suppression than others, especially in a car environment. Suppose amp A is noisy because it's a cheaper design and mounted next to a power source, but amp B is dead quiet in the same location because it has balanced inputs and better noise rejection through design? You take away amp B's advantage by removing that extra challenge.


From my understanding, this rule is implemented so that there are no audible cues as to which amp is playing during the challenge.

But again, this is something to look for when purchasing an amplifier but is *completely irrelevant* to the challenge. The challenge was *NOT* designed to determine which amplifier has better noise rejection capabilities.



> Rule #7 *That each amp can be properly driven by the test setup.* This is basically the same as Rule #4, but what about current? Maybe one amp can't handle changes in voltage well. You negate the better amp's ability to shine with voltage irregularities.


This is something to look for when purchasing an amplifier but is *completely irrelevant* to the challenge. The challenge was *NOT* designed to determine which amplifier has better regulation. 



> Rule # 11 *That the channel separation of all amps in the test is at least 30 dB from 20Hz to 20kHz.* With headphones? Will he allow a test of one amp with 30dB separation and one with 85 dB separation?


The rule itself answers your question  



> What I'm saying is that many of these rules go so far to level the playing field in a clinical setting that they lose sight of real world differences that can affect sound.


And these are things that we KNOW will cause changes in sound. The test was *not* designed to experiment with what we _already_ know, and it was *not* designed to determine which amp is "better" or "better suited to _your needs_". The fallacy in your side of the discussion is attributing these claims to the challenge.



> RC's challenge has much more use in a lab than it does in a real world environment where amp differences can be much more profound. That is where I have the problem.


As I've said 3 times in this thread; It's _perfectly_ suited to the real world, *IF* you understand it's claims and it's goals. And based on your discussion thus far, I don't think you do.


----------



## 60ndown

"Reports are that thousands of people have taken the test, and none has passed the test."

if thousands of people have taken the challenge, and no-one has passed, it has to mean something?

http://tom-morrow-land.com/tests/ampchall/index.htm


----------



## rhinodog00

I agree with Squeak and Markz that a watt is a watt. I also agree with them on the point that all amps do not sound the same. I have had at least 5 different amps running my front stage (hat 3's and 1's). My head unit is a drz9255. I never touched any settings,crossover,time alignment,eq,etc. Gains were set properly and yet each and every amp not only sounded different ,but also imaged differently. Some of the amps were arc audio 4150,pdx4.150,fosgate,tru and linear power. Not one was even close to clipping running the 3" mids and 1" tweeters. I listened to chesky's ultimate demo disc with each set up. If an amp is an amp then please tell me why the large difference in sound with each amplifier. Don't tell me it was just a perceived difference. If that was true then why did the imaging change so drastically?


----------



## MarkZ

rhinodog00 said:


> I agree with Squeak and Markz that a watt is a watt. I also agree with them on the point that all amps do not sound the same. I have had at least 5 different amps running my front stage (hat 3's and 1's). My head unit is a drz9255. I never touched any settings,crossover,time alignment,eq,etc. Gains were set properly and yet each and every amp not only sounded different ,but also imaged differently. Some of the amps were arc audio 4150,pdx4.150,fosgate,tru and linear power. Not one was even close to clipping running the 3" mids and 1" tweeters. I listened to chesky's ultimate demo disc with each set up. If an amp is an amp then please tell me why the large difference in sound with each amplifier. Don't tell me it was just a perceived difference. If that was true then why did the imaging change so drastically?


I don't know.

How would an amp contribute to imaging anyway?


----------



## ca90ss

MarkZ said:


> I don't know.
> 
> How would an amp contribute to imaging anyway?


My guess would be slight level differences between channels and possibly a phase difference as well since some amps have one channel out of phase to make bridging easier.


----------



## rhinodog00

MarkZ said:


> I don't know.
> 
> How would an amp contribute to imaging anyway?


----------



## MarkZ

ca90ss said:


> My guess would be slight level differences between channels and possibly a phase difference as well since some amps have one channel out of phase to make bridging easier.


Amps don't have one channel wired out of phase. If it says + and -, it's + and -. But it's possible it might have been wired up wrong on his end.


----------



## ca90ss

MarkZ said:


> Amps don't have one channel wired out of phase. If it says + and -, it's + and -. But it's possible it might have been wired up wrong on his end.





chad said:


> Yep! On amps where you use a positive and negative to bridge as opposed to two positives the phase is flipped 180 degrees on one channel.


....


----------



## MarkZ

If you hook the plus of one speaker up to the + of the left amplifier channel, and the + of the other speaker up to the + of the right amplifier channel, the two speakers will be in phase *with one another*. They label it that way. They typically invert the phase in the preamp stage to account for the out of phase outputs -- so in the end, they're in phase.

What chad was probably referring to is why you often have to hook up to two pluses (or minuses) when bridging.


----------



## Oliver

ca90ss said:


> My guess would be slight level differences between channels and possibly a phase difference as well since some amps have one channel out of phase to make bridging easier.




Between phase , amplitude , crossover slope , equalization ,etc..,


----------



## rhinodog00

They were wired correctly I always triple check everything before applying power. My guess would be differences in levels on the channels. Don't really know ,but they did not all sound the same. Like I said before Markz now that I understand what you and squeak were saying I agree with it.However, no one can make me believe that all amps are equal. Some are definitely superior to others.


----------



## dkh

FoxPro5 said:


> Faith begins were knowledge ends.


I may get into trouble here but I think that's what happened to a certain part of the world where we now have a large percentage of one billion followers who think flying planes into a building will send them somewhere other than into the building.

I used to use (probably faulty) RF amps and I had three... all three of them were very susseptible to picking up noise. I changed one of the amps for a Helix A4 and that part of the noise dissappeared!

What did my religion/experiment teach me - not all amps are made the same.


----------



## ~thematt~

In its simplest form, RC's challenge is simply saying that you shouldn't purchase an amplifier based on its sound. 

That, and there are NO measurements and NO indications outside of those we know (power, gain, noise, distortion, frequency response and ouput impedance) that contribute to the sound. 

Compounded to that, we can replicate changes in sound via the above, by simply adding cheap modules and parts to distort the signal in someway. So in effect, we can make a cheap amplifier sound like an expensive amplifier, without the expense.

It doesn't matter whether you believe it or not. Its no less entirely accurate (and holistically provable), despite your disagreement.


----------



## DS-21

dkh said:


> I may get into trouble here but I think that's what happened to a certain part of the world where we now have a large percentage of one billion followers who think flying planes into a building will send them somewhere other than into the building.


Damn straight being a bigot will get you in trouble!

It'll get you in trouble because you're completely wrong, and furthermore completely ignorant all polling data of the region. To say nothing of the spate of recent articles in the Western press pointing out how that schmuck and his handful of followers have only alienated the mainstream more over the last 8 years.


----------



## fliplyricist1

After replacing my old xtant x series with a dls A4 and keeping all other parts of my system constant, I could not believe how much better my front stage sounded. And that's not just because I 'knew' it was a high class amp, but immediately I noticed subtle nuances in tracks that I had never heard before with the xtant...and the front stage just seemed so much more 'defined' and 'airy.' Really hard to explain, but I noticed the difference immediately. Crazy. It may be because the amp has built in processing (burr brown chips?) if that makes a difference. But I could definitely tell the difference right away. 

_Or maybe I'm just crazy._ : o


----------



## br85

fliplyricist1 said:


> After replacing my old xtant x series with a dls A4 and keeping all other parts of my system constant, I could not believe how much better my front stage sounded. And that's not just because I 'knew' it was a high class amp, but immediately I noticed subtle nuances in tracks that I had never heard before with the xtant...and the front stage just seemed so much more 'defined' and 'airy.' Really hard to explain, but I noticed the difference immediately. Crazy. It may be because the amp has built in processing (burr brown chips?) if that makes a difference. But I could definitely tell the difference right away.
> 
> _Or maybe I'm just crazy._ : o


Or maybe they is actually a measurable difference somewhere between your two amps? One thing worth remembering is that exact rated rms power is almost never the same as the one printed on the box. Maybe your new amp has more headroom. But it could be a lot of things. One thing is for sure though, if it actually is different in sound (i.e. not psychoacoustic) then it will be a measurable difference somewhere.


----------



## fliplyricist1

br85 said:


> Or maybe they is actually a measurable difference somewhere between your two amps? One thing worth remembering is that exact rated rms power is almost never the same as the one printed on the box. Maybe your new amp has more headroom. But it could be a lot of things. One thing is for sure though, if it actually is different in sound (i.e. not psychoacoustic) then it will be a measurable difference somewhere.


Could be...I know that the dls is indeed rated higher in terms of 'on paper' power, however, I have the levels set extremely conservative at only 1/2 gain and 'audibly' at the same levels as the xtant in terms of relative volume on the headunit. But you could very well be right.


----------



## MarkZ

Review the thread before arriving at your conclusions.


----------



## dkh

DS-21 said:


> Damn straight being a bigot will get you in trouble!
> 
> It'll get you in trouble because you're completely wrong, and furthermore completely ignorant all polling data of the region. To say nothing of the spate of recent articles in the Western press pointing out how that schmuck and his handful of followers have only alienated the mainstream more over the last 8 years.


Being a bigot is nothing to do with blindly following faith - using a real world example of how faith can lead you to nowhere.

and, just for the record, I am a bigot - I believe, rightly or wrongly, that everyone is equal no matter where they live as long as they live in accordance with where they are living rather than imposing their will on the native land.

Now, going back to the post - faith has no place in the science of sound as someone pointed out.


----------



## Hillbilly SQ

Hillbilly SQ said:


> i picked "c" only because i've heard differences between my memphis and crossfire amps. i've had multitudes of experience with several different memphis and crossfire amps and the memphis amps just sounded warmer and more laid back to me. the crossfires seemed to be more sterile sounding and such. they almost sounded artificial. comparison was made with onboard crossovers off and actively crossed with my headunit.
> 
> disclaimer: my comments could easily be disproven if someone really wanted to put their mind to it. my comments are just annicdotes and there are too many variables for my comments to be taken with any seriousness at all. my guess is the memphis amps have a touch of distortion in them causing the warmth to be introduced.


touching up on my post over a year ago switching from a memphis mca3004 and mcd500 to a pg xenon 100.4 and 400.1 made all the difference in the world. i'm sure it's because the xenon 4-channel births at 50 more watts per channel and the headroom is keeping everything more dynamic even at high volumes. the mcd500 births at a little more than the xenon mono amp and it shows SLIGHTLY as the memphis had more gonads to it but the xenon sounds cleaner on the sub. i also could probably get by with less than half of what i'm sending to my sub 99% of the time.

what's in the future of this hillbilly's amp purchases? possibly zed or zuki if patrick will come out with a mono amp that will do in the area of about 500 REAL watts at 2 ohms. that would be what 15 watts by his rating?


----------



## Oliver

His mono will do 500 watts 

of course it is rated a little lower than my stereo amp that does 12.5 watts per channel [Linear Power 2.2 HV {1 horsepower or thereabouts ~ 746 watts }.


----------



## LCat

My experience in High End audio tells me what all amps sound different as long as your system is good enopugh to let you hear difference


----------



## ~thematt~

LCat said:


> My experience in High End audio tells me what all amps sound different as long as your system is good enopugh to let you hear difference


So all I really need is to spend $100k on a good turntable, $200k on good cables, and $300k on good fancy looking speakers, and I'll be able to tell the audible difference between a $500 amplifier and a $1500 amplifier.....?

Ausome. Now all I'll need is $500k, and a noisy amplifier.


----------



## br85

~thematt~ said:


> So all I really need is to spend $100k on a good turntable, $200k on good cables, and $300k on good fancy looking speakers, and I'll be able to tell the audible difference between a $500 amplifier and a $1500 amplifier.....?
> 
> Ausome. Now all I'll need is $500k, and a noisy amplifier.


You missed those little porcelain things that cost a few hundred dollars each that lift your $200k cables off the ground to reduce "earth noise" (from the ground). Geez, your system would stink. You'll also need your own 3 phase power plant and some proper regulation to power your 1024 red hot 300B tubes per side in single ended class A.

And then, if you don't have your head in a vice to stop minor movements from taking you out of the stereo sweet spot, it'll sound like rubbish and you'll be back to upgrading your cables again to get ones that are more "danceable".


----------



## tspence73

Put me in with the RC challenge pool.


----------



## tspence73

Yeah, I'm not from around these parts. I didn't even look at the last date something was posted. Sorry. :blush: Car audio hobbyists aren't very nice people, are they? Oh wait, you called me an idiot and don't even know me. That explains that.


----------



## tspence73

lilmsprelude said:


> I Can't believe I am going to respond...
> 
> Yes, YOU.. YOU ARE AN IDIOT!!
> 
> What, you think I havent watched your posts, visited the other sites you contaminate...read your senseless babble!?! Let alone Your audacity to Argue in opposition of the truth?
> 
> I DON'T Like you Because you Reject The REALITY, (The Damn FACTS!!!,) that these fine ENTHUSIASTS provide to you, and the GENEROUS amount of Patience they have shown you, all out of the kindness of just being a fellow member of an Outstanding Forum.
> 
> You SIR need to just SHUT your effin mouth and swallow your pride; have a little Humility for GOD's SAKE!!!!!
> 
> OH, and for your information, we are quite the Jovial crowd with YEARS and YEARS of combined experience NOT Only in car audio, but also in studio and proffessional audio, we are also electricians, designers, engineers, IT, business owners, Proffesionals and Hobbyists.... and SO MUCH MORE!!!
> It is NOT that we are discrediting you and your rich background.. you have already done that yourself! Thank you for searching--I assume that is how you found this old thread.. but for heavens sake... PLEASE dig deep into those putrid bowels of yours and dig out a little common sense.
> 
> or GTFO already... the humor of your ignorance has passed. Now you are just irritating.


Actually, for your information, this thread recently came back to the top on it's own. I didn't 'find' it. I think someone else found it, clicked in a 'vote' on the poll, it then came to the top and then I assumed it was recent and posted in it by mistake. 

No, this is not a jovial crowd. I'm not right on everything, but I haven't been wrong on everything either. Most of the time I have been attacked on preferences, not facts. If you don't like a post of mine then don't respond to it. You went out of your way to accuse me of bringing up an old thread when I actually didn't. You jumped to conclusions when you should have just given the benefit of the doubt.

Also, I never once went out of my way to insult you as you have done to me. I'm supposed to be the idiot then? Also, not all of the advice I've been given has been accurate, truthful or even an answer for what I asked. Hell, half the time the 'experts' have completely misunderstood my question. 

Anyway, please, don't bother to respond to my posts again. I don't care to hear from you or any of the others who are being jerks lately. Just simply move on. Believe me, I will when it comes to your posts.


----------



## Mooble

tspence73 said:


> Actually, for your information, this thread recently came back to the top on it's own. I didn't 'find' it. I think someone else found it, clicked in a 'vote' on the poll, it then came to the top and then I assumed it was recent and posted in it by mistake.


He's right. He wasn't the one to dredge it up, someone else did. I saw it pop up last week and he probably thought it was current.

Anyway, it was already decided conclusively that amps obviously do sound different because they don't measure the same. If they didn't sound different, RC wouldn't make you disable all features on them before taking his test.

It's nice to have the last word.


----------



## t3sn4f2

Mooble said:


> He's right. He wasn't the one to dredge it up, someone else did. I saw it pop up last week and he probably thought it was current.
> 
> Anyway, it was already decided conclusively that amps obviously do sound different because they don't measure the same. If they didn't sound different, RC wouldn't make you disable all features on them before taking his test.
> 
> It's nice to have the last word.


It's actually, clipping amps sound different all other amps sound the same.


----------



## Mooble

t3sn4f2 said:


> It's actually, clipping amps sound different all other amps sound the same.


Or ones that have artificial EQing, or any other form of sound manipulation, which many do.


----------



## t3sn4f2

Mooble said:


> Or ones that have artificial EQing, or any other form of sound manipulation, which many do.


True, fortunately we are in the EQ era where those factory EQ curves just become part of the cars sound signature that we will deal with anyway when tuning.


----------



## capnxtreme

tspence73 said:


> Hell, half the time the 'experts' have completely misunderstood my question.


First of all, no. Second of all, whose fault would that be? Third, GTFO.


----------



## farshad

Hello guys,
I was one of those people who couldn't expect that "All modern solid state amps sound the same while being used within their clipping limits"! and differences you do hear will be down to incorrect level matching ... I didn't stop looking for an amp with perfect sonic signature for my taste and speakers through these years!! no matter how many articles and double blind tests proved Option 2 in the pool but ... ?! until ... 
reading the thread "Best Hu for the money" and some posts in this thread from nice members about sound of different cd players, and again I started searching and reading, article after article , test after test and post after post ... ! i had already read so much posts and DBT's but i think even have read much more tests and posts in Home Audio/Car Audio forums after that nice thread !! :huh: 
now I'm really convinced that there should be no difference, I'm going to do a level-matched test and don't think I'll buy an amp for its sound anymore. don't get me wrong, I'll continue buying Zapco , ARC , Audison , Helix and etc but not for their sound.

thanksss to you great guys!!!


----------



## farshad

Hello dear friend's,
I have not yet done a level-matched listening test but would like to know what are your thought's aobut this long article? werewolf , MarkZ , squeak9798 , DS-21 and others ...

*Do Measurements Matter?
Designers Speak Out*
Cardas Audio


----------



## DS-21

I was about to simply post that I don't need to read it. Simply because it's on that feckless con-man George Cardas' website, it must be worthless. Then I read it.

By and large, my gut reaction holds. Cardas' own contribution is typically moronic, Jeff Rowland sounds like a fool, Myles Astor reminds me why I used to want to throw up every time I used to read one of his "Astor's Place" columns in Stereophile,. Notably, all of them start from the false premise that we can hear things we can't measure. And all of them ignore entirely that even if that premise were true, things that we can't measure but can hear would turn up as statistically significant sonic differences in double blind subjective same/different listening, because simply speaking none of them have the intellectual capacity to understand such things.

However, the contribution from Linkwitz was excellent, focusing on the importance of power response (without calling it such) and ignoring the ******** debate about wires, amps, digital sources, and other audio commodities entirely. Thiel had some interesting and useful things to say. And the last paragraph of Nelson Pass's article was on point, too. He's also right that the discussion is, frankly, boring, because the issue has been resolved in the mind of everyone who's not either stupid or trying to sell you something.


----------



## 60ndown

DS-21 said:


> I used to want to throw up every time I used to read one of his "Astor's Place" columns in Stereophile,. Notably, all of them start from the false premise that we can hear things we can't measure. And all of them ignore entirely that even if that premise were true, things that we can't measure but can hear would turn up as statistically significant sonic differences in double blind subjective same/different listening, because simply speaking none of them have the intellectual capacity to understand such things.


we cant measure emotion, but we can definitely hear it.

holographic image?

id say that some systems can do things that cant be measured.


----------



## t3sn4f2

60ndown said:


> we cant measure emotion, but we can definitely hear it.
> 
> holographic image?
> 
> id say that some systems can do things that cant be measured.


Absolutely right, emotion from an illusion.


----------



## squeak9798

60ndown said:


> we cant measure emotion, but we can definitely hear it.


I'm sure if we put you in the proper neurological measurement device, we could get a relative "measure" of your emotional response based on the brain's activity  



> id say that some systems can do things that cant be measured.


I'd say there's no stereo system in existence that does anything unexpected based on what the mathematical models and proper measurement techniques predict it would.


----------



## paulc35

3.5max6spd said:


> All op amps/input stages are not created equal and very few amplifiers can completely bypass/isolate them from the original signal.


Very true and it is the basic quality of the parts and the sum of the parts that give us that difference. The job of the amp is to get out of the way and take the signal from the H/U and amplify it, but its just not that easy since so many amps are made differently, which creates the end sound we either love,hate, or just say its ok. Unlike high end home audio car audio amp manufacturers don't really give you any info as to what parts they used.
I think to this day just looking at the inside of amps the Helix and Brax are the only amps that i've seen that use top notch parts. (capacitors,resistors,power supply,isolation of critical components,etc.)

For me I've always loved Tube/hybrids in home audio. Tubes in the front end (preamp) and solid state for the muscle in the rear allow me to play around with the sound by swapping tubes for NOS tubes. I'm referring to my home audio setup, but there are a few Tube/Hybrid amps in car audio. I haven't got one yet. Almost had the Helix tube/hybrid. 

Its all subjective. If it sounds better to you then it is and thats what its all about.


----------



## MarkZ

paulc35 said:


> Very true and it is the basic quality of the parts and the sum of the parts that give us that difference. The job of the amp is to get out of the way and take the signal from the H/U and amplify it, but its just not that easy since so many amps are made differently, which creates the end sound we either love,hate, or just say its ok. Unlike high end home audio car audio amp manufacturers don't really give you any info as to what parts they used.


The "quality" of the parts is the single most overrated aspect of an audio amplifier. All it tells us is how rugged the amplifier might be (if we're talking about the high current parts -- output transistors, rectifiers, etc). Aside from that, it has only a relatively small influence on the noise, distortion, and frequency response characteristics of the amplifier. That's dominated by the DESIGN, LAYOUT, and CONSTRUCTION.

I'll take an amplifier designed correctly over one that uses special capacitors, super tolerance resistors, and even "high end" op amps.


----------



## DS-21

60ndown said:


> we cant measure emotion, but we can definitely hear it..


Emotion is an aspect of _musical performance_, not the reproduction thereof.


----------



## paulc35

MarkZ said:


> The "quality" of the parts is the single most overrated aspect of an audio amplifier. All it tells us is how rugged the amplifier might be (if we're talking about the high current parts -- output transistors, rectifiers, etc). Aside from that, it has only a relatively small influence on the noise, distortion, and frequency response characteristics of the amplifier. That's dominated by the DESIGN, LAYOUT, and CONSTRUCTION.
> 
> I'll take an amplifier designed correctly over one that uses special capacitors, super tolerance resistors, and even "high end" op amps.


Well Mark I believe thats what I'm saying. (If its designed correctly). I assure you parts and tolerance have an influence. Look at some of the stated signal to noise ratios. You want more hiss, or less. >80db, or>100db

If design,construction and layout was all there was to it then we would all have Sony amps, which we don't and why? because of simply how its made and the damn fine parts it uses. I'm sure Pyle amps are designed correctly. 

PS-Small influences is usually what makes us happy

If it sounds better to you then that is all that matters


----------



## MarkZ

paulc35 said:


> Well Mark I believe thats what I'm saying. (If its designed correctly). I assure you parts and tolerance have an influence. Look at some of the stated signal to noise ratios. You want more hiss, or less. >80db, or>100db


Which parts in particular influence the noise spec? I can't think of any. Again, with the possible exception of op amps before or in the input stage (which you don't need anyway). Maybe the quality of the connections, but that's quite another thing.



> If design,construction and layout was all there was to it then we would all have Sony amps, which we don't and why? because of simply how its made and the damn fine parts it uses. I'm sure Pyle amps are designed correctly.


Have you ever looked at a Sony schematic? The ones I've seen tend to have very very simple input and VA stages. And, contrary to popular belief, fewer components is BAD in terms of reducing distortion and noise.

In other words, the Sony amp is a bad design. It has very little to do with the quality of parts.


----------



## paulc35

MarkZ said:


> Which parts in particular influence the noise spec? I can't think of any. Again, with the possible exception of op amps before or in the input stage (which you don't need anyway). Maybe the quality of the connections, but that's quite another thing.
> 
> 
> 
> Have you ever looked at a Sony schematic? The ones I've seen tend to have very very simple input and VA stages. And, contrary to popular belief, fewer components is BAD in terms of reducing distortion and noise.
> 
> In other words, the Sony amp is a bad design. It has very little to do with the quality of parts.



Go read some PDFs on Zapco's website on their DC amps.

Your reading to much into what I'm saying. You argue design and I say that the design and construction includes good quality parts, or very poor parts, which leads to bad design.
If a company uses parts that don't have tight tolerances then you call it bad design. Construction must have proper heat dissipation, or the amps keep shutting down and die early. This is all in (Proper Design) and quality of power supply. Lets talk the big one. Cross talk between channels background noise. Isolation of critical components and Damn good power supplies. Again you will argue proper design. I agree with you.

I'm saying there are companies that have a much better design and construction over many others. Like Zed Audio. 


Zapco PDF DC amps

Don't listen to me my opinions only

Take care


----------



## MarkZ

paulc35 said:


> Go read some PDFs on Zapco's website on their DC amps.
> 
> Your reading to much into what I'm saying. You argue design and I say that the design and construction includes good quality parts, or very poor parts, which leads to bad design.
> If a company uses parts that don't have tight tolerances then you call it bad design. Construction must have proper heat dissipation, or the amps keep shutting down and die early. This is all in (Proper Design) and quality of power supply. Lets talk the big one. Cross talk between channels background noise. Isolation of critical components and Damn good power supplies. Again you will argue proper design. I agree with you.
> 
> I'm saying there are companies that have a much better design and construction over many others. Like Zed Audio.
> 
> 
> Zapco PDF DC amps
> 
> Don't listen to me my opinions only
> 
> Take care


You're confounding lots of different variables and lumping them all into a single thing called "design", which kind of leaves us back at square one. Let me just clarify my position then. The "quality" of the PARTS you use and the DESIGN can be two different things. You can use bargain basement parts and crappy tolerances but put them into circuits that make the quality of the part and their tolerance unimportant. In fact, not only can tolerances be made to be unimportant, but the actual values of the components can be made not to matter (within a reasonable range, of course)!

For example, in a typical input stage, you can use current mirrors and other "active" circuitry to generate a constant current that's important for the transconductance between the input stage and VA stage of an amplifier. When you do this, the actual values of most of the resistors within the circuit become pretty meaningless. Doing this, however, means a higher parts count, which I assume increases the cost of the design and manufacture.

In most schematics I've seen, manufacturers don't do this. As folks like Doug Self and others have written in their design books, its absence results in higher distortion figures. Similarly, the absence of BJT buffers between the supply rails and the input stage can give rise to higher crosstalk (something you mentioned) and poorer PSRR figures.

Another example has to do with the bias tracking circuit. Some have argued (again, I think Doug Self is one...) that poor bias tracking can be one of the dominant sources of distortion in good designs. For those of you who don't know what it is, bias tracking generally refers to monitoring the temperature of the output stage transistors, making predictions about how the temperature will affect the transistors' electrical properties, and adjusting the bias voltage accordingly. That way, both transistors aren't both "on" at the same time or "off" at the same time (which gives rise to "gm-doubling" and crossover distortion, respectively). This is commonly done by monitoring the temperature somewhere on the heatsink. Some have argued that monitoring the temperature of the output transistors DIRECTLY leads to much more accurate bias tracking. I bring this up because this is an example of improving a DESIGN considerably without having to incorporate higher quality parts.

So what's better? A GOOD design that incorporates current mirroring and buffering and accurate bias tracking with bargain basement parts? Or a design that DOESN'T incorporate these things but has expensive bypass caps, designer op amps, and precise tolerance resistors?

And you bring up isolation, layout, construction, etc. I agree that these are important attributes of an amplifier DESIGN. But they have almost nothing to do with the quality of the parts (except maybe the board itself).

So I'll just reiterate my original point before we veer too far away here... The "quality" of the parts used is secondary to the actual design strategy. And by design strategy, I'm mostly talking about things like layout, circuit design, grounding strategies, etc.


----------



## paulc35

MarkZ said:


> You're confounding lots of different variables and lumping them all into a single thing called "design", which kind of leaves us back at square one. Let me just clarify my position then. The "quality" of the PARTS you use and the DESIGN can be two different things. You can use bargain basement parts and crappy tolerances but put them into circuits that make the quality of the part and their tolerance unimportant. In fact, not only can tolerances be made to be unimportant, but the actual values of the components can be made not to matter (within a reasonable range, of course)!
> 
> For example, in a typical input stage, you can use current mirrors and other "active" circuitry to generate a constant current that's important for the transconductance between the input stage and VA stage of an amplifier. When you do this, the actual values of most of the resistors within the circuit become pretty meaningless. Doing this, however, means a higher parts count, which I assume increases the cost of the design and manufacture.
> 
> In most schematics I've seen, manufacturers don't do this. As folks like Doug Self and others have written in their design books, its absence results in higher distortion figures. Similarly, the absence of BJT buffers between the supply rails and the input stage can give rise to higher crosstalk (something you mentioned) and poorer PSRR figures.
> 
> Another example has to do with the bias tracking circuit. Some have argued (again, I think Doug Self is one...) that poor bias tracking can be one of the dominant sources of distortion in good designs. For those of you who don't know what it is, bias tracking generally refers to monitoring the temperature of the output stage transistors, making predictions about how the temperature will affect the transistors' electrical properties, and adjusting the bias voltage accordingly. That way, both transistors aren't both "on" at the same time or "off" at the same time (which gives rise to "gm-doubling" and crossover distortion, respectively). This is commonly done by monitoring the temperature somewhere


----------



## paulc35

MarkZ said:


> You're confounding lots of different variables and lumping them all into a single thing called "design", which kind of leaves us back at square one. Let me just clarify my position then. The "quality" of the PARTS you use and the DESIGN can be two different things. You can use bargain basement parts and crappy tolerances but put them into circuits that make the quality of the part and their tolerance unimportant. In fact, not only can tolerances be made to be unimportant, but the actual values of the components can be made not to matter (within a reasonable range, of course)!
> 
> For example, in a typical input stage, you can use current mirrors and other "active" circuitry to generate a constant current that's important for the transconductance between the input stage and VA stage of an amplifier. When you do this, the actual values of most of the resistors within the circuit become pretty meaningless. Doing this, however, means a higher parts count, which I assume increases the cost of the design and manufacture.
> 
> In most schematics I've seen, manufacturers don't do this. As folks like Doug Self and others have written in their design books, its absence results in higher distortion figures. Similarly, the absence of BJT buffers between the supply rails and the input stage can give rise to higher crosstalk (something you mentioned) and poorer PSRR figures.
> 
> Another example has to do with the bias tracking circuit. Some have argued (again, I think Doug Self is one...) that poor bias tracking can be one of the dominant sources of distortion in good designs. For those of you who don't know what it is, bias tracking generally refers to monitoring the temperature of the output stage transistors, making predictions about how the temperature will affect the transistors' electrical properties, and adjusting the bias voltage accordingly. That way, both transistors aren't both "on" at the same time or "off" at the same time (which gives rise to "gm-doubling" and crossover distortion, respectively). This is commonly done by monitoring the temperature somewhere on the heatsink. Some have argued that monitoring the temperature of the output transistors DIRECTLY leads to much more accurate bias tracking. I bring this up because this is an example of improving a DESIGN considerably without having to incorporate higher quality parts.
> 
> So what's better? A GOOD design that incorporates current mirroring and buffering and accurate bias tracking with bargain basement parts? Or a design that DOESN'T incorporate these things but has expensive bypass caps, designer op amps, and precise tolerance resistors?
> 
> And you bring up isolation, layout, construction, etc. I agree that these are important attributes of an amplifier DESIGN. But they have almost nothing to do with the quality of the parts (except maybe the board itself).
> 
> So I'll just reiterate my original point before we veer too far away here... The "quality" of the parts used is secondary to the actual design strategy. And by design strategy, I'm mostly talking about things like layout, circuit design, grounding strategies, etc.



We agree!!
I just listen to my ears when I can. Thats the most important part.
I want Helix Tube/Hybrid. Now thats what my ears like


----------



## AAAAAAA

Don't be so quick to think your ears know what they are hearing


----------



## farshad

Hello again,
thanks for the responses, I'd like to know what equipment should be used in the amps test? is it possible to match the levels with a DMM?


----------



## Oliver

up ^^^^


----------



## MarkZ

a$$hole said:


> up ^^^^


Haha you SUUUUUCCCCKKK.


----------



## sn95chico

I switched from Rockford amps to JL amps there was a huge difference 

The Rockford had way to much treble and i always had to turn down my eq gains on the highs 

with the jl amp i had way better sounding car 

I can tell a difference 


but when i went From JL to Zapco i did not hear a difference as much and i did with the rockford


----------



## chad

and here we go... 

the rockfords, at least many, have a preset EQ curve


----------



## paulc35

Being one who comes from Hi End home audio, tube, solid state, and hybrids and some very good car systems I can tell you that amps do alter the sonic signature. Now without hurting anyone's feelings there is a lot of variables in a good system and speakers are going to be as important as the amp. If you have poor speakers, or God forbid using the factory speakers then you probably won't hear a difference in a $100 amp vs a $500 amp. If on the other hand you actually care about how vocals, midrange, and instruments sound and not just how many bolts you can vibrate loose with your subs then I guarantee you will hear difference with different amps. All designers build their amps the way they think offers the truest output, which we know varies. That's why some designers are legends (Zed Audio) and why JL Audio has such a large following. My oppinion only.


----------



## ErinH

Jim, you bastard!!!!!


Yes, all amps sound different. I put grille cloth over my RCAs to cut down on 30khz and up.


----------



## MarkZ

Here's my sonic signature.


----------



## ErinH

MarkZ said:


> Here's my sonic signature.


your view is tainted.




get it?


----------



## lycan

the poll needs to be changed ...

The new poll should be : who even _understands_ option 2 ? 

or : what's the difference between option 2 & 3 ? How does one rule out option 2, in favor of option 3 ?

or : does anyone even care about this post? :laugh:


----------



## ErinH

^ it's simple:
#2: if they measure the same, they sound the same

#3: no matter what science says, I still believe Pluto is a real planet.


----------



## lycan

bikinpunk said:


> ^ it's simple:
> #2: if they measure the same, they sound the same
> 
> #3: no matter what science says, I still believe Pluto is a real planet.


... but i swapped amps, and it sounded different! So that MUST be option #3, right ?


----------



## Hernan

Of course all amps sounds a bit different, but if they measure the same they probably sounds alike.

So 3 and 2 are my choices.

Good article:

http://www.stereophile.com/features/the_carver_challenge/index.html


----------



## Oliver

Snowflakes are like fingerprints [ all are different ], all though in a snowstorm they all seem the same !

Wikipedia:


> Snowflakes are conglomerations of frozen ice crystals which fall through the Earth's atmosphere. They begin as two snow crystals which develop when microscopic supercooled cloud droplets freeze. Snowflakes come in a variety of sizes and shapes. Complex shapes emerge as the flake moves through differing temperature and humidity regimes. Individual snowflakes are nearly unique in structure. Types which fall in the form of a ball due to melting and refreezing, rather than a flake, are known as graupel, with ice pellets and snow grains as examples of graupel.


----------



## MarkZ

a$$hole said:


> Snowflakes are like fingerprints [ all are different ], all though in a snowstorm they all seem the same !


Yet they all _look_ the same to us because our eyes are very imperfect machines.


----------



## BadSS

Hernan;1073510)
Good article:
[url=http://www.stereophile.com/features/the_carver_challenge/index.html said:


> Stereophile: The Carver Challenge[/url]


Yep,, I ran across that article about a year ago when doing a little surfing. Very fitting link for this thread.


----------



## Hillbilly SQ

I have a couple amps on the way to try out (bought one but another is being sent to try out to see which I like better). I chose this brand because he builds his amps right and doesn't charge an arm and a leg for them. One is a regular production model and the other was a custom order someone flaked out on. The custom amp is supposed to be a little more over built so insanely dynamic music doesn't get brick walled when the amp runs out of steam. It will also pull well over 100a if I let itThe amp I just described will probably sound different than the production model at times because the designer gave it a "no holds barred" design to pull all the power it needs when needed. I'll send the one I don't want back after playing with both. And my x100.4 is starting to fook up


----------



## Oliver

Hillbilly SQ said:


> It will also pull well over 100a if I let itThe amp I just described will probably sound different than the production model at times because the designer gave it a "no holds barred" design to pull all the power it needs when needed.


Make sure your charging system is able to supply the power required to run this amp, otherwise you'll pay dearly !


----------



## Hillbilly SQ

a$$hole said:


> Make sure your charging system is able to supply the power required to run this amp, otherwise you'll pay dearly !


160a alty stock


----------



## Oliver

Some sounds different


----------



## lycan

read the poll carefully ... as of today, 9 members think that two amps with gains set VERY differently (one at max gain, other at min gain) will sound the same. Filters don't matter either ... according to the language of the poll.

These threads always tend to devolve into two camps :

1. All amps sound the same NO MATTER WHAT. For example: two amps from the same production line, with one set at *max gain* and the other set at *min gain*, will sound exactly the same. At least 9 members are in this camp. One amp set with a 200Hz high-pass, other set with a 200Hz low-pass ??? No matter ... these amps will sound the same, because after all, they are still amps ... and all amps sound the same.

2. No amps can possibly sound the same, NO MATTER WHAT. Nothing you can possibly do with "mere electronics" can possibly make two amps sound sonically indistinguishable. There's some "magic connection" ... some gestalt, some "symbiotic communion" ... between amps & speakers that transcends measurement, that transcends all known electronic theory. At least 150 members are in this camp.

BOTH camps are flat out wrong.


----------



## cvjoint

The poll is now closed it appears. When I made this thread I had slightly different beliefs on the issue. 

Over time I came to one realization:
We should have all voted *"All amps. sound the same IF they measure the same."*

The reason is simple, it is the ONLY option given that has been tested thoroughly. The RC challenge can be replicated and similar results will ensue. Regardless of what YOU believe, unless you have an experiment set up that is properly administered and replicable that supports your view, personal beliefs are of little importance. 

In the world of car audio the _majority is not always right._ In the world of car audio we are often either uninformed or irrational. 

I hope this thread will underline these features of this hobby and make a larger portion of our community challenge their own views more thoroughly.


----------



## RattyMcClelland

I had the Genesis Series 2 & 3 amplifiers running my mids and tweeters and then changed to the Sinfoni AMplitudes.

The difference was very apparent without touching the headunit. Made the Genesis sounds peaky and harsh, the Sinfoni was more dynamic, transparent and had way way more headroom despite running less power.

Tell me its Psychoacoustics all you want. i dont care. I heard a difference. A big difference and im not alone on that. Shame though as i loved my Genesis Amps. It was a nice modified DA110. 

But the Sinfonis seem to play exactly what the headunit is giving it. Not adding anything but amplifying the signal..


----------



## lycan

RattyMcClelland said:


> I had the Genesis Series 2 & 3 amplifiers running my mids and tweeters and then changed to the Sinfoni AMplitudes.
> 
> The difference was very apparent without touching the headunit. Made the Genesis sounds peaky and harsh, the Sinfoni was more dynamic, transparent and had way way more headroom despite running less power.
> 
> Tell me its Psychoacoustics all you want. i dont care. I heard a difference. A big difference and im not alone on that. Shame though as i loved my Genesis Amps. It was a nice modified DA110.
> 
> But the Sinfonis seem to play exactly what the headunit is giving it. Not adding anything but amplifying the signal..


so ... based on THAT experience, which way would you vote in the poll?

Your choice is between option #2 and option #3. Please THINK, and choose carefully 

Then, please tell us why you discarded one of your options in favor of the other.


----------



## schmiddr2

This is hilarious. :laugh:

Lycan you crack me up. You ask people the exact questions that they are not asking themselves.

If they "heard a difference" they just say because they know it was the amp; all the while not asking why the amp sounds different. :laugh:


----------



## RattyMcClelland

Well im not standing 100% by my answer as im still learning.
But id say option 3 from my limited knowledge.
Different amplifiers use different internals, different resistors, caps, wire lengths and so forth.
Surley the signal gets manipulated ever so slightly passing through these components.

I had a 23w x 2 Genesis B40 on my tweeters and i preferred the sound it produced to my DA110. B40 sounded smoother and less peaky. The Sinfoni 45.2x bettered it further adding the obvious more power but more transparency.
Did the DA110 on the mids and then the 45.2x. The 45.2x was more delicate and dynamic. Way more headroom with less power and fuller rounded bass. Again more transparent.

Of course these are all what i heard with my ears. And my ears preferred the Sinfonis. 

Now when i switched the amps over i cannot guarantee the gains were all identical. They were all on minimum and i used the headunit to level match but TA and EQ were left well alone, amp crossovers either never existed or were bypassed.


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## lycan

honestly NOT picking on Ratty ...

BUT, this issue comes up ALL THE TIME in the great "amp debate" 

Is there any _informative_ difference between these two statements:

A. "_I swapped amps, and the difference was night & day. Therefore, amps sound different! And all this crap about measuring doesn't mean anything. Amps are different!_"

B. "_I swapped amps, and the difference was night & day. SO, we decided to measure WHY they sounded different. We measured gain, power, frequency response, noise & distortion ... and sure enough, there was a few dB difference in the frequency response of the two amps._"

*In other words ... if you just swap amps, and hear a difference ... what exactly have you done to rule out option #2? How do you know whether or not that difference you heard can be attributed to gain, power, frequency response, noise or distortion ... unless you MEASURE them and compare the results?

Swapping amps and hearing a difference does NOT automatically lead to option #3.

Option #2 ALSO explains, and allows, that AMPS SOUND DIFFERENT. Option #2 just goes one step further, to explain WHY.*

Or, try this : Ratty i'm going to suggest that the difference you heard was because one of the amps has a gentle EQ curve built-in, in order to sound better. Is there any way we can possibly determine if my suggestion is true? Wouldn't you be interested in the answer?


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## RattyMcClelland

lycan said:


> honestly NOT picking on Ratty ...






lycan said:


> Or, try this : Ratty i'm going to suggest that the difference you heard was because one of the amps has a gentle EQ curve built-in, in order to sound better. Is there any way we can possibly determine if my suggestion is true? Wouldn't you be interested in the answer?


Yes please fire away, id be interested to know.


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## lycan

RattyMcClelland said:


> Yes please fire away, id be interested to know.


how can we _possibly_ determine if the difference we heard between two amps was because one of them had a non-flat frequency response?

Do we consult a fortune teller?

Do we consult the "golden ear" down at the stereo store?

Do we maybe mount them in a different car, and hope that tells us something?

Maybe try the amps on different speakers? Change the speaker wire?

How can we possibly resolve this dilemma?

Does option #2 in the poll anticipate ... and allow ... that amps sound different?


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## RattyMcClelland

lycan said:


> how can we _possibly_ determine if the difference we heard between two amps was because one of them had a non-flat frequency response?
> 
> Do we consult a fortune teller?
> 
> Do we consult the "golden ear" down at the stereo store?
> 
> Do we maybe mount them in a different car, and hope that tells us something?
> 
> Maybe try the amps on different speakers? Change the speaker wire?
> 
> How can we possibly resolve this dilemma?
> 
> Does option #2 in the poll anticipate ... and allow ... that amps sound different?


Some interesting points. But im still not convinced. 
I cannot believe a 2 channel Sony Xplode amp will sound the same as a £4k Audiowave CR amp given that they are setup correctly.
What about the op amps and the Analogue to ditial conversions in the amps. Amp classifcation. Its ability for dynamic headroom.

We need some amp builds on here.


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## lycan

Don't focus on components ... instead, focus on the SIGNAL you measure at the two output terminals. After all, that's _exactly_ what your loudspeakers are doing 



RattyMcClelland said:


> Some interesting points. But im still not convinced.
> I cannot believe a 2 channel Sony Xplode amp will sound the same as a £4k Audiowave CR amp given that they are setup correctly.


They may, or may not. It's more than "set up". That Xplode amp may very well have a midrange EQ "built-in". Or, it may roll off the high treble, or low bass. Or, it may not make rated power, into a complex load, without significant distortion. HOWEVER ... in any & all of these cases ... the effects are MEASURABLE. And if they measure the same as any other amp, then the two amps have no choice but to sound the same.

If they MEASURE differently, then they will SOUND differently. Option #2 in the poll *allows & anticipates* that amps sound different. HOWEVER ... you can't "rule out" option #2, without MEASURING the amps. Just swapping amps, and "hearing a difference", does NOT rule out Option #2 ... this is simple logic, nothing more.


> What about the op amps and the Analogue to ditial conversions in the amps. Amp classifcation. Its ability for dynamic headroom.
> 
> We need some amp builds on here.


If opamps, capacitor type, solder type and Class of operation do NOT impact the *power, gain, frequency response, noise & distortion* of the signal at the amplifier's output ... then they can NOT impact the sound either.

An amplifier provides a _signal_ at it's output terminals. That _signal_, is the only thing the speaker "knows". And the ONLY characteristics of a signal are : power, gain, frequency response, noise & distortion. In fact ... a couple of these are redundant. The only things needed to characterize a signal are frequency response, noise & distortion.

*In short :* you swapped amps, and heard a difference? FINE  You should pick option #2 in the poll (unless proven otherwise).


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## t3sn4f2

RattyMcClelland said:


> Some interesting points. But im still not convinced.
> *I cannot believe a 2 channel Sony Xplode amp will sound the same as a £4k Audiowave CR amp given that they are setup correctly.*
> What about the op amps and the Analogue to ditial conversions in the amps. Amp classifcation. Its ability for dynamic headroom.
> 
> We need some amp builds on here.


Exactly, they are likely to _when set up correctly_. Correctly being the variable that no one understands or follows. 

View attachment 20062


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## gijoe

t3sn4f2 said:


> Exactly, they are likely to _when set up correctly_. Correctly being the variable that no one understands or follows.
> 
> View attachment 20062


Because "correct" settings don't exist. It isn't a question of whether the amp is set up "correctly" it's a question of whether or not they are set up to measure the same. There is no correct gain, you set the gain to what works in your install. There is no correct FR, you set your EQ to what works in your install. 

If you set the amps to measure the same, they will sound the same. I'm not saying it is always possible to get 2 amps to measure the same, but I think with some pretty basic tools it's not difficult to get most amps to measure close enough to be indistinguishable.


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## lycan

Ratty, please consider this :

I put super-dooper opamps in my new power amplifier. The loudspeaker connected to my amplifier ONLY sees the voltage presented to it's terminals. So ... if the opamp swap did _not_ impact the voltage at the speaker terminals, how could the speakers possibly sound any different with the new opamps in the power amp?

"_Well,_" you say, "_the swap DID impact the voltage at the terminals!_" FINE. All i want to know is this : did the opamp swap impact the gain, power, frequency response, noise or distortion of the signal at the output terminals? There's simply no other "aspect" of the signal that can be impacted  And ... all of these are measurable! There's nothing about the "sound" of a voltage at loudspeaker terminals that can't be measured & quantified.

So ... which is it? Did the opamp swap impact (improve) the : frequency response, noise or distortion of the signal?

There's no other choice.


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## RattyMcClelland

That does make more sense Lycan..you word it quite easily. 

So do alot of amps have an EQ curve in them?


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## lycan

RattyMcClelland said:


> That does make more sense Lycan..you word it quite easily.
> 
> So do alot of amps have an EQ curve in them?


An EQ curve may take the form of bass roll-off in a vacuum tube amplifier (due to output transformer bandwidth, on the low end). Or it may be intentional ... at least one known example (i forget the brand, somebody remembers). Probably more, but nobody bothers to measure amplifiers, it seems ... many would rather attribute the sound to "mysterious SQ pixie dust".

More likely: one of the amplifiers _fails_ to make rated power into a complex speaker load. And distortion results.

Bottom line : if the output terminals of two audio power amplifiers MEASURE the same, they have no choice but to SOUND the same. How could connected loudspeakers possibly react to anything else?

And the list of "parameters" to measure is actually quite short 

"_But wait, what about the super-hyper-flux-geometry wires used in MY amplifier?_" *If the type of wire doesn't impact the frequency response, noise & distortion of the signal at the output of the amplifier, the loudspeakers ... or, your ears ... can't possibly recognize the difference.* The loudspeakers don't know how much money you spent on that wire  they only know the voltage that's driving them 

"_But i swapped two amps, and i KNOW they sounded different!_" Fine ... let's assume you really did a double-blind test, so you weren't biased by brand names or purchase price. Have you really PROVEN that the sonic difference was NOT something that can be measured? Or ... did you just assume it was somehow mysteriously beyond the ability of science to _explain_ the difference?

EDIT : *You swapped two amps, and heard a difference. Fine ... pick Option #2 in the poll, because it agrees with you ... AND it explains why.*


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## cvjoint

That's fine as a theoretical exercise however I remember seeing the Zapco tests and virtually all those amplifiers have negligible distortion right up to clipping. I'm inclined to believe that the rise in distortion only happens in the vicinity of the clipping point. It ain't no speaker.


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## Dangerranger

cvjoint said:


> That's fine as a theoretical exercise however I remember seeing the Zapco tests and virtually all those amplifiers have negligible distortion right up to clipping. I'm inclined to believe that the rise in distortion only happens in the vicinity of the clipping point. It ain't no speaker.


Very true. Amps tend to have lowest distortion right before the point of clipping too as it's where the devices are most efficient. Most of the better Zeff designed amps use Bipolar output devices which are more linear overall, that combined with the feedback means they are clean, but when they do clip, they clip HARD. There's no gentle transition into clipping. Not that there is such a thing, but some amps more than others.


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## Dangerranger

cajunner said:


> to me, all we're really saying is that a commercially produced amplifier will follow known performance curves that are analogous to the inaudible threshold of the human hearing mechanism.


True, I'd probably change "will" to "should". The biggest offenders are the extreme low end and the extreme "high end".


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## Oliver

Hmmmm


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## Winno

And who's going to defeat the filtering, cross overs, processing, etc in their amp for the sake of this?
I would say that many, if not most will by their amps BECAUSE of the filtering, cross overs, processing, etc.

I think that despite these additions to amplifiers there's still differences in amps but these additions and features ADD to the differences we hear.


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## AAAAAAA

I miss lycan


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## subwoofery

I know it has been beaten to death already but I like to post my findings since it hasn't been discussed extensively in the other thread... 

Here's what I "believe" from comparing different tests done for some amps: 


subwoofery said:


> Buy looking at some tests done on some amps, I've noticed a trend - the warm sound we hear from some amps doesn't come from the freq response but from the distortion figures over the whole spectrum (usually above 1kHz). Here are a few examples:
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> I also want to point out that the distorsion figures we see doesn't necessarily mean that "warm" amps have the highest "Total Harmonic Distortion" numbers.
> Said to be "Warm" amps:
> Audison - THD @ 4 ohm is 0.138%
> DLS Ref - THD @ 4 ohm is 0.029%
> Mosconi - THD @ 4 ohm is 0.07%
> Sinfoni - THD @ 4 ohm is 0.02%
> 
> Said to be "Clinical" amps:
> Brax X2 - THD @ 4 ohm is 0.44% (not a mistake)
> DLS TA2 - yes, this hybrid tube amp actually exhibits more of a clinical sound. It's THD @ 4 ohm is 0.046%
> Focal - THD @ 4 ohm is 0.028%
> Zapco - THD @ 4 ohm is 0.005%
> 
> Let's discuss
> 
> Kelvin


I do believe that amps that measure the same, sound the same and that differences are attributed to things that CAN be measured like gain, power, frequency response, noise or distortion

You can see in my quoted post that distortion can be measured and can have a very large difference from 1 amp to another... therefore, I also do believe amps can sound different and that the brain is complex enough with the ability to discern little differences when A/Bing 2 things... 

I'm not talking about if you can hear 0.1%, 1% or 5% distortion here... 

Kelvin


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