# How much sub clipping is safe?



## ImK'ed (Aug 12, 2013)

Before i decide i cant live with 500rms on sub, im gonna try re adjusting gains at the moment i used dmm and -5 tones on my jl 900/5 amp but my friend has a oscilloscope so should i use some bass heavy tracks and leave sub connected and then hook up o scope and keep turning up gains till i clip?


----------



## 14642 (May 19, 2008)

use -10dB sine waves to set your mids and highs and adjust the bass amp so that it sounds balanced.


----------



## ImK'ed (Aug 12, 2013)

Say i want most power out of sub channel?


----------



## qwertydude (Dec 22, 2008)

If you're trying to set the gains right, you don't worry about getting the most power. Even if you cut the power in half it only reduces your output by 3 db's. Actually less if you factor in things like power compression and a subwoofers natural tendency to become less efficient at higher excursion.

But if you have overboosted bass heavy songs and set the gains for those to prevent clipping your bass might sound pretty weak when playing your normal music.

Since you will have access to an o-scope. I would say set it normally, 3/4 volume on the head unit and you should set the gain so that you're just about clipping. This ought to maximize the power you're using but keep your amp from unnecessarily clipping when you turn it up.

It might also be good to get the remote level control. JL finally got this feature right on the HD amps, previously they used the knob to control bass boost which runis the equalization and frequency response of the subwoofer. Now on the HD amps they use it to control gain. So you can use it to set your gains a little higher and cut it some with the knob. That way for songs where the bass is recorded light you can turn it up a little and if it's too strong and you start to hear some distortion you can back it off a little.

Don't use it as a volume knob though. What I do is that I keep my bass knob in the middle and set the gains accordingly. Then I can boost or cut the gain level with the knob and know that the middle is where it should be to play safely and balanced with a neutral setting.


----------



## ImK'ed (Aug 12, 2013)

Good idea! Ive got sub level control on hu so i can use that like a sub level remote? Its a sub volume not bass boost, alpine 9855r head unit. And when tuning with o scope should i leave sub connected? So there is a load on amp?


----------



## squeak9798 (Apr 20, 2005)

You don't need an oscope to set a gain. In fact it's probably worse since it gives you a false sense of security.

As Andy said set it by ear so it sounds balanced. It's not more complicated than that.


----------



## qwertydude (Dec 22, 2008)

It's not a false sense of security. If you set it so that it never shows clipping that's as safe as you can get.

The only problem is if the amplifier puts out more clean power than the subwoofer really can handle. That's when setting it by ear is the safer route. But as it stands now the OP I believe has a WGTi. That can most definitely handle 500 wattts so pushing the subwoofer past its power limit isn't much of an issue as much as pushing the amplifier into clipping.


----------



## squeak9798 (Apr 20, 2005)

qwertydude said:


> It's not a false sense of security. If you set it so that it never shows clipping that's as safe as you can get.


It absolutely is a false sense of security. 

Yes, you can set it with a 0db test tone at maximum volume and "never clip", but you also won't get any real power from the amp, have no available headroom to account for source level differences and 99% of users will not be happy with the performance of the system. Pretty easy to prove this true by looking around the forums and seeing all of the threads posted where people were complaining about a lack of system output and asking how to fix it when setting the system with either a DMM or oscope and a 0db test tone. Nobody with any understanding sets their system in this manor.

So, since NOBODY sets their system with a 0db test tone and sets it to "never clip" because the results on the average system are TERRIBLE, people instead use a -6db or -10db test tone to set their system...*like Andy, one of the most respected users on the forum, suggests above. *Now people think that because they used an oscope to set their gain it's "right" and will "never clip", when in fact they clearly can either by playing a track that has a higher average recording levels than anticipated, peaks in the music exceeding the level the gain was set at, or by playing a song with a much lower recording level and turning the volume knob up higher to compensate (since the baseline "safe setting" is now out the window).

So yes, due to the variable nature of the source material it's every bit as inexact and inaccurate as setting it by ear only with the false sense of security that it's set "perfect" and to "never clip". 

Set it by ear. It's no more complicated than that. You don't need anymore equipment than you ear and a screw driver. Sure, it might clip a little, but if it's not damaging anything and you can't hear it...it doesn't matter. So who cares? Setting it with an oscope can allow the exact same thing to happen so what's the difference? Other than the oscope incorrectly makes you think it's foolproof when it's not. That's the only difference.

EDIT: And that's without even getting into the other issues an oscope doesn't take into account like proper level matching, capabilities of the amp compared to power handling of the driver, etc etc. all things considered there is never a need to use an oscope. Using your ears and head are the best choice and all that's required in the average system.


----------



## qwertydude (Dec 22, 2008)

I don't think you understand what a false sense of security is. Setting gains with a 0db test tone and an o-scope is a way to 100% guarantee no clipping. I never said it would sound the way you want. I said setting it with the o-scope as such would guarantee you won't clip no matter how loud you crank up the volume. That's 100% safe and 100% secure from preventing clipping. I didn't say it would sound the way you want.

The OP has 500 watts for a subwoofer and want to prevent clipping. If he sets it to prevent clipping and he doesn't get enough bass, the solution isn't to crank up the gains. The solution would be to get a more powerful amplifier or more efficient subwoofer setup.

Read through the many, many posts on this site. GAIN IS NOT A VOLUME CONTROL. You're treating it as such.

And I don't think you understand what 0db means. When you have a source that's peaking at 0db, nothing from that source can ever exceed that level. So setting the gains to not clip at 0db is the safest 100% way to prevent clipping coming out of your amp. Setting gains using -6 db test tones is just a way to ensure that if you have quieter recordings you can turn the head unit volume up and compensate. But setting it with -6db tones does introduce the possibility that if you now have a 0db recording and really crank it up, you'll push your amplifier into clipping. And that's the false sense of security. 0db is 100% safe since no signal from the source can ever exceed that and push your amp into clipping.

And per your edit yes this doesn't take into account level matching for sound. The OP has 500 watts for a subwoofer and want to prevent clipping. If he sets it to prevent clipping and he doesn't get enough bass, the solution isn't to crank up the gains. The solution would be to get a more powerful amplifier or more efficient subwoofer setup. Level matching a subwoofer that's weaker than your mains will inevitably lead to clipping if you don't have a balanced system.


----------



## edzyy (Aug 18, 2011)

Setting for no clipping leaves a lot of clean power on the table. 

A soft clip is good for the soul


----------



## qwertydude (Dec 22, 2008)

That is the point I was trying to make.



> 3/4 volume on the head unit and you should set the gain so that you're just about clipping. This ought to maximize the power you're using but keep your amp from unnecessarily clipping when you turn it up.


That ensures you're just about at maximum power level since you are just about clipping. When you can see the tops of the waves just start to flatten out. Don't go cranking the gains anymore.

I don't know where squeak is getting the idea that somehow setting the gains to prevent clipping is dangerous and gives a false sense of security. If you can never push your amp into clipping, you'll never damage your equipment. Even if it leaves a little extra power on the table, I don't possibly see how that can be dangerous.

But setting it by ear, unless you know how to do this right, that can be dangerous to your equipment. Bass is very difficult to hear distortion. Many people have set their gains by ear and then find out later they were constantly pushing their subs into clipping and either blew their subs or sent their amps into protect. Bandpass boxes are especially prone to this. Since they tend to muffle the sounds of clipping very well.

Using an O-scope is just like using a DMM to set your gains, only it's a more accurate way to do it than just by ear alone or just by DMM which too can show a mismatch if its not a true RMS DMM Since a non RMS DMM will show clipping as a higher AC voltage than it really is. This is how some people end up thinking "Wow my amp is over 100% efficient!" Nope you're just clipping the hell out of it.


----------



## squeak9798 (Apr 20, 2005)

qwertydude said:


> I don't think you understand what a false sense of security is.


Pretty sure I do. Though it doesn't appear you understand the point of the conversation.



> Setting gains with a 0db test tone and an o-scope is a way to 100% guarantee no clipping. I never said it would sound the way you want.


Then it was a pretty stupid point to make. I never said you "couldn't" set a system so it never clipped. Matter of fact I specifically stated that you could, but if you did you wouldn't be happy with the results. Pay attention. You are arguing a point I never made. 



> I said setting it with the o-scope as such would guarantee you won't clip no matter how loud you crank up the volume. That's 100% safe and 100% secure from preventing clipping. I didn't say it would sound the way you want.


And I'll reiterate that it was a ridiculous point to make when no one would set their system in such a manor or be pleased with the results. So not even sure what this has to do with my comments. 



> The OP has 500 watts for a subwoofer and want to prevent clipping. If he sets it to prevent clipping and he doesn't get enough bass, the solution isn't to crank up the gains. The solution would be to get a more powerful amplifier or more efficient subwoofer setup.


Again, not even remotely close to what I said. 



> Read through the many, many posts on this site. GAIN IS NOT A VOLUME CONTROL. You're treating it as such.


It most certainly can be used as such. You've NEVER used it to level match? Any one who has is using their gain incorrectly? In the past decade that's all I've used the gain for...level matching. Of course you don't want to turn it up so high that it clips so bad the distortion so audible and/or equipment is at risk of being damaged. But otherwise it most definitely can be used as a volume control.

*Read Andy's statement above. That is PRECISELY what he is suggesting as well yet I don't see you arguing with him. Why is that ??*



> And I don't think you understand what 0db means.


Of course I understand what 0db means. You just lack reading comprehension and have it stuck in your head we're in this "argument" when 3/4 of your post so far is completely irrelevant to what I've said. You're too focused on being "right" to understand why you're wrong or that we're not even disagreeing on a certain point.



> So setting the gains to not clip at 0db is the safest 100% way to prevent clipping coming out of your amp.


Right, and we've established that it leaves a **** tn of power on the table so no one does it. So stop bringing it up. It's irrelevant. 



> Setting gains using -6 db test tones is just a way to ensure that if you have quieter recordings you can turn the head unit volume up and compensate.


No, you are confused. You could use a -6db test tone, but if you set the gains with the volume at 100% you wouldn't have any extra headroom for lower recording levels. Using a -6db test tone is used to allow for higher average power from the amplifier, resulting in higher average output from the system for a given volume setting. Setting the gain at a volume level less then 100% (I.e. At 75% of max volume) is to allow headroom for lower recording levels. 




> But setting it with -6db tones does introduce the possibility that if you now have a 0db recording and really crank it up, you'll push your amplifier into clipping. *And that's the false sense of security. *


THIS IS EXACTLY WHAT I SAID, SO WHAT THE HELL ARE WE ARGUING ABOUT ???? I even pointed out the instances of when this would occur. This proves my point that this whole time you've been the only one not understanding the conversation and arguing points that didn't need argued just to feel "right" and that you're smarter than the other party. 

All you've done is argue points I never made or points that are completely irrelevant, and restate the same thing I've already said only you state it like it's this big revelation. Reading comprehension and stop arguing just to argue. 



> 0db is 100% safe since no signal from the source can ever exceed that and push your amp into clipping.


And nobody does this. So stop bringing it up. It's irrelevant and I already said this was the case in my original post. 



> And per your edit yes this doesn't take into account level matching for sound. The OP has 500 watts for a subwoofer and want to prevent clipping. If he sets it to prevent clipping and he doesn't get enough bass, the solution isn't to crank up the gains. The solution would be to get a more powerful amplifier or more efficient subwoofer setup. Level matching a subwoofer that's weaker than your mains will inevitably lead to clipping if you don't have a balanced system.


The edit was more of an "in general" statement and not necessarily this particular instance.


----------



## squeak9798 (Apr 20, 2005)

qwertydude said:


> That ensures you're just about at maximum power level since you are just about clipping. When you can see the tops of the waves just start to flatten out. Don't go cranking the gains anymore.


Right, *and if you only listened to that test tone the system would be perfect.* 

What you are ignoring is the variable nature of the source material. Different recording levels, etc all makes it an exercise in futility if you plan to actually enjoy the system. As soon as any of those variables in the source material change and your " accurate setting" goes right out the ****ing window. Lower recoding level and you turn the volume up a little higher...now how do you know where the clipping point is ? YOU DON'T. Higher recording level and you turn the volume up to the same point. Guess what? CLIPPING. 

BUT because it was set with an oscope, the user thinks it's clip-free when that isn't the case. THAT'S the false sense of security that you are not getting. And no, NO ONE SETS THEIR GAIN WITH A 0db Tone, so don't bother bringing it up. 

All variables considered it's no more accurate than by ear, only the user mistakenly believes it's set "perfect" amped to "avoid clipping" so they stop using their head and ears and end up blowing **** anyways. 



> I don't know where squeak is getting the idea that somehow setting the gains to prevent clipping is dangerous and gives a false sense of security.


See above. You are the one not getting it, not me.

Oscope, DMM, DD1, etc all also ignore proper level matching between components, power of the amp compared to power handling of the speakers, other system settings, etc etc. all of which also render the scope methods moot and the ear a better option. You are ignoring this as well. 


> If you can never push your amp into clipping, you'll never damage your equipment. Even if it leaves a little extra power on the table, I don't possibly see how that can be dangerous.


See Andy's suggestion of -10db above. Stop focusing on me. Tell Andy he's wrong. You argue with me because you feel superior, I've yet to see you argue with Andy when he said essentially the same thing I have with fewer words. 



> But setting it by ear, unless you know how to do this right, that can be dangerous to your equipment. Bass is very difficult to hear distortion. Many people have set their gains by ear and then find out later they were constantly pushing their subs into clipping and either blew their subs or sent their amps into protect. Bandpass boxes are especially prone to this. Since they tend to muffle the sounds of clipping very well.


Right. Millions of gains set by ear around the world every year with no damage to equipment. Over how many decades of car audio. It's not even close to as difficult as you make it sound. (Pun intended?) 



> Using an O-scope is just like using a DMM to set your gains,


Right, they are both equally unnecessary and inaccurate :laugh:

Set it by ear and enjoy. It's a gain, not rocket science. No tools other than your head and ears necessary.


----------



## qwertydude (Dec 22, 2008)

Now you're trying to pick apart every sentence I write and doing it wrong in the process.

here's your quote that started it all.



> You don't need an oscope to set a gain. In fact it's probably worse since it gives you a false sense of security.



Ok so tell me EXACTLY why using an o-scope to properly set your gains is a false sense of security. Even though you don't need it, the op has access to one and would like to know how to use it.

DON'T TELL ME WHY IT WOULD SOUND BAD. Why is it dangerous? To me having a system that doesn't clip no matter what you do is very safe. Saying it gives you a false sense of security somehow implies that it is dangerous.

Explain this to me. It's something you've been trying to avoid.


----------



## SPLEclipse (Aug 17, 2012)

Squeak, I think qwerty is just disagreeing on the "false sense of security" thing, and his point is valid. Other than a simple conflict of terms both of you have good advice.

Just to add to the discussion, a little clipping is perfectly acceptable. In fact a LOT of clipping is perfectly acceptable if it's not destroying your equipment, but heavy clipping is definitely noticeable by ear (and sometimes smell). Make sure you check your voltage after you set the gain and reconnect the equipment though. Sagging voltage supply at the amp will start to kill things quickly because it's a positive feedback loop. Because the OP is only running 500w, I think he will be perfectly safe to set things by ear as Andy recommended, but on a higher watt amp or a car with a less-than-stellar electrical system, that would be horrible advice.


----------



## qwertydude (Dec 22, 2008)

So nobody sets their gains with 0 db test tones?

Using Test Tones to Set Amplifier Gain

Autosound 2000 Disc Four Amplifier Optimizer Test CD at Crutchfield.com

That test CD uses 0db test tones.

And if you think setting gains with a -10 db test tone is safe, tell that to people with music that has a wide dynamic range. Classical music like I listen to will go right up to 0 db.

Try listening to Telarc's rendition of Tchaikovsky's 1812 Overture. If you set your gains with -10db test tones and those canons go right up to 0db, if you don't have your gains set right and you want to listen to it at reference levels, you'll blow your subs up or at the minimum drive them into severe clipping. Ever hear what 10 db's of overdrive sound like? It's not pretty. That's like trying to push a 100 watt amp to output 1000 watts. I don't care how much headroom you have that's not safe.

Modern music as a result of the loudness war makes it safe to use -5 db test tones since rarely will there be any dynamic range that can push your system to its limits.

So if I set my system with a -10 db test tone I will most definitely push my amps into severe clipping.

When the violins in a concerto are playing softly and you turn the volume up so that it sounds like a violin playing at normal listening levels it should be about 80 db in loudness, when you get an orchestra going full blast you'll get 120+ db's, 137 db's is the world record by the way.

Unless you set your gains right, trying to listen to music with that kind of dynamic range will sound like crap on the louder sections when you do push your amps into clipping because of using -10db test tones.

Andy is right, more than likely -10db test tones would be safe for the kind of music the OP listens to. But to say that setting gains with 0 db is giving you a false sense of security, that is wrong. It gives you the safest way to run your system, and this is especially important if you listen to music with dynamic range.


----------



## squeak9798 (Apr 20, 2005)

qwertydude said:


> Ok so tell me EXACTLY why using an o-scope to properly set your gains is a false sense of security. Even though you don't need it, the op has access to one and would like to know how to use it.
> 
> .....
> 
> It's something you've been trying to avoid.


:laugh::laugh:

SomethingI've been avoiding? **** man, I've done it atleast twice now. It's not my fault you lack the reading comprehension to understand it.

Read post 8 and 13. If you don't get it, that's your fault not mine.


----------



## squeak9798 (Apr 20, 2005)

SPLEclipse said:


> but on a higher watt amp or a car with a less-than-stellar electrical system, that would be horrible advice.


Over the past 2 decades I haven't done it with anything other than my ear and haven't damaged anything. Millions of people around the world over several decades have successfully set gains by ear. Again, not nearly as difficult as you would like to perceive.


----------



## squeak9798 (Apr 20, 2005)

qwertydude said:


> So nobody sets their gains with 0 db test tones?
> 
> Using Test Tones to Set Amplifier Gain
> 
> ...


:laugh:

Linking to 1 article giving bad advise doesn't make you right. 

BTW, that disc also includes -10db test tones. Do you know why? Because A2K, Richard Clark and David Navone, suggested 1:1 gain overlap (0db) for line level sources *and 3:1 gain overlap at the amplifiers*. Do you see a trend? Guys like Richard Clark, Davod Navone, Andy above recommend -10db tones....seems to be the suggestion of most of the industries top veterans....

I see your article and raise you a post by someone who actually matters. Here is RC's comments on 3:1 gain ratio at the amp: http://www.audiogroupforum.com/csforum/showthread.php?p=51692&highlight=gain#post51692



> And if you think setting gains with a -10 db test tone is safe, tell that to people with music that has a wide dynamic range. Classical music like I listen to will go right up to 0 db.


3:1 gain ratio was/is very popular among SQ competitors. You don't think they listen to dynamic music? You don't think RC listened to dynamic music in the GN? You don't think Andy listens to dynamic music?



> Now you're trying to pick apart every sentence I write and doing it wrong in the process.


Gain setting, YOU are doing it wrong :laugh:


----------



## qwertydude (Dec 22, 2008)

Posts 8 and 13 still don't explain why 0db is dangerous. The entire posts of 8 and 13 only relate to why you think it would sound bad, perhaps too "quiet" But not dangerous. Again referencing your own material.

You've set gains by ear for 20 years. So have I, and I've also set them by O-scope and will agree that it is the more conservative setting, I've never blown my system up either. So how can it be more dangerous to use more conservative settings? That's the point you're not explaining very well. Each time you try to do it you end up just trying to say it wouldn't sound good, or it would sound quieter, or it won't be level matched. But you still avoid why it's dangerous, which is what your initial post is implying. Why does setting gains with a 0db test tone offer a false sense of security? What danger does it pose to your equipment?

3:1 gain structure? [Archive] - CARSOUND.COM Forum

This is the point I'm trying to make and that you keep ducking.



> I'm not arguing against a 3:1 gain overlap. I agree wholeheartedly with David Navonne's fundamental premise that you want the hottest possible unclipped signal at the end of the processor chain and that you would like every part of that chain (head unit, crossover, etc.) to clip at roughly the same time. That is going to give you the max available S/N ratio and dynamic range. (For the sake of discussion, lets call this signal 3 volts for a typical system.)
> 
> I further agree that if you want to have the ability to extract max SPL from your amplifiers, the 3:1 ratio makes sense (1 volt in = max undistored output). That is going to give you the ability to drive the amps into hard clipping, even with a source disc that is low in level. Of course, a sensible user is probably not going to twist the volume knob to the point where they are constantly driving the amp into hard clipping all the time, but the ability is there from the basic gain structure.
> 
> ...


"That is going to give you the ability to drive the amps into hard clipping, even with a source disc that is low in level." Did you read that? It gives you the ability to drive your amps to hard clipping even with a low level source disc. My music will go to 0db and if I turn up the volume it will most definitely clip the hell out of the amplifier. That's why I want to set my gains using 0db.

Read up on that 3:1 argument. You can most certainly drive your amps into severe clipping with 3:1 gain settings. Setting the gains with a 1:1 structure would be 100% safe. And that's what I do because I don't want any clipping in my signal path. It's conservative sure. But I also make sure that I have enough amplifier overhead to begin with so that I can still drive the speakers to the db levels I want and guarantee they're getting 100% clean power.

This is the reason why so many of us on this site have so much amplifier headroom, often 2-3 times the RMS ratings on the speakers. Not only does it give you very good dynamic range ability but it does so without stressing your amps to their limits.

There's a difference between increasing the average power using a 3:1 gain structure and having music where you'll actually hit that ceiling and the high levels of short term average power ends up clipping and you can hear it. In the post above using a 1:1 gain structure, it's claimed you only use 10% of the average power the amp is capable of. Music itself only reaches its peak about 10% of the time anyways. But if you start getting areas where you do use the peaks and are driving them into clipping, you won't hear it the majority of the time with the quieter sections, but you will most definitely hear it during the peaks. This is dynamic range compression, something I want to avoid. And also something pretty much eliminated by the loudness wars. Just my music never suffered from the loudness wars so setting gains with 0db test tones still makes sense to me since I also have the amplifier headroom to ensure I get the loudness I want and never clip the amps.

So saying nobody sets gains using 0db test tones is ridiculous. A lot of people do it. I've done it before. And even people on the Steve Meade Forum understand that 0db is the safest, most conservative way, to set gains. It might make your music a little quieter, meaning you might have to turn the volume on the head unit up a little, but it's not giving you a false sense of security.

So, how many out there set gains with 0db instead of -5db tones? - Head Units-Processors and Eq's - SMD Forum

So even though it's safe to push your amps into clipping a little. If this is a site dedicated to sound quality, even if it's feasibly safe to clip a little. Wouldn't you want to know that you're not clipping at all if maximum sound quality is what you're striving for? Sure your music is only distorting at the peaks, but for classical music the peaks is where you'll absolutely hear the distortion and I most certainly have when setting with -10 db. Slightly less so with -5db but I most certainly did hear it when my music went to 0db.

So again tell me why does it give you a false sense of security? At what scenario will it be dangerous to equipment?


----------



## Hanatsu (Nov 9, 2010)

Holy crap... what a discussion. I use -8dB tones to set gains then level match with the DSP. Always worked for me, never in my life blown a woofer because of my gain setting. Using 0dB tones to set gains wastes a lot of available power on the MAJORITY of records out there, but sure if you got a ton of power available and feels the output is adequate you can go ahead and set gains with a 0dB tone, nothing wrong with that - it's indeed the most conservative and safe way to set gains. 

There have been lots of times I've just set it by ear because I knew I was never gonna push the system to it's limits anyway, if it sounds bad just turn down the volume... It can be an issue with BP enclosures that mask the distortion, they are more prone for failure cause the the distortion ain't very audible.

Edit: Transient distortion is less audible than steady state distortion but having too little power will effectively reduce the dynamic range of the record. Having enough power and a good enough recording to hear reductions in DR or transient distortion while still enjoying the music is a luxury everyone don't have (those good recordings tend to be 'boring' music IMO. I tend to listen to lots of that "compressed to ****" music lol)


----------



## Hanatsu (Nov 9, 2010)

I also wanna add that settings gains right is also about the noise floor. You wanna have as high unclipped input as possible to keep the possibility of noise down. ^^


----------



## squeak9798 (Apr 20, 2005)

qwertydude said:


> Posts 8 and 13 still don't explain why 0db is dangerous. The entire posts of 8 and 13 only relate to why you think it would sound bad, perhaps too "quiet" But not dangerous. Again referencing your own material.


Holy **** sticks, learn to read. I never said 0db was dangerous. I said it was so conservative that no one with any understanding uses it. How many times do I have to repeat the same **** over and over again in this conversation with you? Reread the thread. If you don't get it, then that's on you, not me. Reading comprehension would do you well. It's all here. I don't think anyone but yourself is confused on my viewpoint. You disagree and that's fine, you are entitled to your wrong opinion. But I'm over continually being asked to answer the same questions that I already answered because you just can't seem to get it. 

No need to try to school me on amplifier headroom. You are talking to a guy who was running 600w per side to his passive components, and wrote an article in favor of headroom for another forum. I am familiar with the concept of amplifier headroom and used it successfully for a decade. 

At this point we can agree to disagree. You can stick with Crutchfield and SMD, I'll stick with the knowledgable folks and pioneers of the industry. 

Trying to avoid all clipping is ridiculous and completely unnecessary, just like feeling you need to have a device to properly set a gain. No wonder you support both, they go hand in hand...


----------



## qwertydude (Dec 22, 2008)

> In fact it's probably worse since it gives you a false sense of security.


What do you think this means? Everyone who reads this, and actually has a fundamental understanding of English, would equate your phrase with thinking that setting 0db gains is somehow dangerous.

Hiding behind a piece of plywood in a gunfight is a false sense of security. IE you might feel you're safe, but in reality you're not. That's what a false sense of security means.

Setting your gains with a 0db test tone is not a false sense of security. It's exactly the opposite. It's so conservative that there is absolutely no way you could drive your amps to clipping. There is nothing false about that. It's 100% true.

You think I'm dense for trying to point out the very first error you refuse to admit? When all the posts you put yourself more support my point of view that setting gains with 0db is safe, conservative but still safe. And that the more dynamic your music, the more important it is to set gains more conservatively.



> What you are ignoring is the variable nature of the source material. Different recording levels, etc all makes it an exercise in futility if you plan to actually enjoy the system. As soon as any of those variables in the source material change and your " accurate setting" goes right out the ****ing window. Lower recoding level and you turn the volume up a little higher...now how do you know where the clipping point is ? YOU DON'T. Higher recording level and you turn the volume up to the same point. Guess what? CLIPPING.
> 
> BUT because it was set with an oscope, the user thinks it's clip-free when that isn't the case. THAT'S the false sense of security that you are not getting. And no, NO ONE SETS THEIR GAIN WITH A 0db Tone, so don't bother bringing it up.


You see this is more wrong thinking. If you set your source with a 0db test tone and an o-scope, a quieter recording will still come out quieter. Unless the music itself was clipping, you can never drive your amp into clipping with a quieter music piece because the source would never drive the head unit to its clipping in the first place, and since the source isn't driven into clipping, how could it possibly send the amp into clipping?

So yes setting with a 0db test tone can lead to quieter output when playing back quieter recordings. But that's what setting the gains with the head unit volume at 3/4 is for. You get a 25% leeway to bump up the volume with the head unit when the recording is quieter. So turn up the volume a little and where is your clipping point? It's exactly the same as before, you'll just never reach it with the quieter recording. This is the reason I'm harping on your advice, it makes zero sense. You're assuming that somehow the recording level in your music somehow changes the clipping point of your system. It doesn't.

If your music is recorded at such low levels that's not a problem with your settings, that's a problem with the music you're playing. And setting your gains to play your quietest music to clipping is certainly a dangerous game to play.


----------



## squeak9798 (Apr 20, 2005)

qwertydude said:


> What do you think this means? Everyone who reads this, and actually has a fundamental understanding of English, would equate your phrase with thinking that setting 0db gains is somehow dangerous.


No one with an understanding of English who has read this entire thread took that statement to mean 0db when I've clearly explained that in later posts. You therefore self-admittedly lack reading comprehension and a fundamental understanding of the English language. You are the only person not getting it, because that is the only premise in which you could possibly "win" so you are sticking to your guns on it despite the fact I've clarified on multiple occasions.



> Hiding behind a piece of plywood in a gunfight is a false sense of security. IE you might feel you're safe, but in reality you're not. That's what a false sense of security means.


A false sense of security is also believing you have your system set to "avoid clipping" because you set it with an oscope/DMM/DD1 and a non-0db test tone when in fact due to the variable nature of the source material and other factors clipping is in fact still possible. Again, due to your admitted lack of reading comprehension and fundamental lack of understanding of the English you are the only person not grasping this concept. 



> Setting your gains with a 0db test tone is not a false sense of security. It's exactly the opposite.


It's also ill-advised as it's a waste of amplifier power, a very poor method in which to set a gain and a moronic pursuit to "avoid all clipping" 



> It's so conservative that there is absolutely no way you could drive your amps to clipping.


It's so conservative no one with any understanding of the subject uses it as a method of setting a gain.



> There is nothing false about that. It's 100% true.


I've already said that. It's also 100% true that it's a really poor method of gain setting and no one with any understanding uses such a method. 



> You think I'm dense for trying to point out the very first error you refuse to admit?


No, you are dense for thinking you are continually pointing out an error I didn't even make, and every time I point that out you simply don't get it. You take one sentence and ignore everything else I've said which completely clarifies my initial comment, why your understanding of that statement is wrong and you still just don't understand what is going on. That's what makes you dense. 



> When all the posts you put yourself more support my point of view that setting gains with 0db is safe, conservative but still safe.


And this is another example of why you are dense. I've already stated in multiple posts that it is correct that a 0db gain setting at 100% volume is "safe" but so dumb of an idea that no one with any understanding does it. You are the only one not getting it because you are so focused on being "right" instead of understanding what I'm saying. I bet this is the 5th time I've said it in this thread, yet here you are trying to argue with me about it yet again like it's some new revelation.



> You see this is more wrong thinking. If you set your source with a 0db test tone and an o-scope, a quieter recording will still come out quieter. Unless the music itself was clipping, you can never drive your amp into clipping with a quieter music piece because the source would never drive the head unit to its clipping in the first place, and since the source isn't driven into clipping, how could it possibly send the amp into clipping?


No, the only wrong thinking here is yours. Another example of your lack of reading comprehension. If you had read I specifically stated that since setting gains with a 0db test tone is ridiculous and no one with any sense does it I was not referring to those instances, because I already knew that would be your only response. 

However, you are still wrong. If one were to set the gain at, say, 75% of maximum volume with a 0db test tone and they turn the volume up past 75% it's still entirely possible for them to clip the amp. 

Now, if you are suggesting that someone instead set their gain with a 0db test tone at 100% volume all in the pursuit of avoiding clipping I would laugh in your face as that would be the dumbest method of gain setting someone could ever use.



> So yes setting with a 0db test tone can lead to quieter output when playing back quieter recordings.


It's quieter when playing back any recording. 



> But that's what setting the gains with the head unit volume at 3/4 is for. You get a 25% leeway to bump up the volume with the head unit when the recording is quieter. So turn up the volume a little and where is your clipping point? It's exactly the same as before, you'll just never reach it with the quieter recording.


BUT YOU DON'T KNOW WHERE THE NEW CLIPPING POINT IS ON THE VOLUME RANGE, SO IT NOW COULD BE POSSIBLE TO CLIP THE AMPS. That is what you are not getting, and holy **** I already pointed this out I post 13. How in the hell are you not getting this ???



> This is the reason I'm harping on your advice, it makes zero sense.


The only thing not making sense here is you. From your lack of reading comprehension to your terrible advise that users set their gains with a 0db test tone in the idiotic pursuit of avoiding any possibility of clipping...to this....



> You're assuming that somehow the recording level in your music somehow changes the clipping point of your system.


The average recording level affects where you turn the volume knob which can affect the clipping especially if it causes you to go past your "safe" volume setting.


----------



## squeak9798 (Apr 20, 2005)

Whatever. I'm done with this thread. You clearly just don't get it, and I,honestly just don't care anymore. I can't explain things any more clearly than I already have, and you just ignore it and stick to the misconception you have in your head. I'm not sure why I cared this long, I shouldn't have especially since it's like talking to a damn wall. You just keep circling back to things I've already clarified in detail but you still misconstrue them, you argue against points I never made, you restate something I already said but say it like it's new information, and your idea of proper gain setting is just laughably bad.


----------



## hot9dog (Mar 23, 2013)

:laugh: your funny:laugh:


----------



## estanley1 (May 4, 2013)

Ho. Lee. ****.


----------



## ImK'ed (Aug 12, 2013)

I did it with dmm last time set it 38.7volts as im running a 3 ohm load so thats about 500 watts with a -5db 40hz tone. Today i did it with same -5db tone but by ear till i heard a faint buzz through sub then slightly back and left it at that, when measured with dmm im getting 44volts. This isnt perfect because im sure i must have some slight clipping with some tunes but i have more bass output and it doesnt sound distorted. I will test it with oscope when i get a chance


----------



## Negolien (May 17, 2010)

These forums can be tedious and tiring with all the measuring and arguing.


----------



## ImK'ed (Aug 12, 2013)

Right tommorow im going to use my friends scope, its a pico scope he using for car diagnostics, should i leave subwoofer connected? And use a -5db tone?


----------



## 14642 (May 19, 2008)

Set the mid and tweeter gains with a scope and a -10dB sine wave and then set the sub amp gains so it sounds good. 

If you can't get enough bass that way, then you either need a bigger amp or you should turn the other amp down. Doesn't have to be any more difficult than that.


----------



## ImK'ed (Aug 12, 2013)

Ok kewl thanks for reply, say i want to set sub at max power how would i do that?


----------



## ccapil (Jun 1, 2013)

Nice thread and wee bit of arguing, lol.
So a truth is : EVERYONE clips their amp, even if it is very very little. If you don't clip your amplifier, then you surely won't be happy with the output and therefore the overall sound. Now to avoid clipping, even minor clipping, either set the gains with a true RMS DMM or an oscope, or both. Using an oscope is a proven way to accualy SEE what the music or sine wave is doing, but it all depends on the track. It changes with every song. Since music is very dynamic, older music that is recorded in higher quality usually has way higher crest factor than say a 2013 recorded song. It all depends, one song you will have no clipping, and other track with a lower crest factor, you could be clipping the amplifer minorly, or a lot. The aim is to set the gain with no clipping at all or just a little, little clipping is FINE, it's when you get into more of a square wave and major clipping happens and problems can occur. Have the gain set to clip when the volume knob is up the higher end of the scale, eg 34/40. For the OP the best solution, possibly, you could think about getting a amplifier with more power and therefore headroom, this will allow for the gains to be lower also, less chance of noise also. BUT that mean more strain on the alt. so I would set your gains by ear, then get a true rms dmm and check your voltage on the terminals doesn't exceed the voltage for 500 watts rms (if you are wired to 500 watts) basically it's just ohms law - voltage = square root of watts x ohms. 
If you set by ear, it is OK, but there's always that one person, who thinks they have the golden ears and can set gains perfectly. You could be setting them to clip majorly. Your better off to use a oscope or multimeter to back that up. You won't be setting the sensitivity so it puts out max power of the amp, it will allow you to have a good overlap with the headunit so you don't overdrive the amp majorly.


----------

