# Gain setting test tones. -10db 1K -5db 40hz, etc



## captainobvious (Mar 11, 2006)

Does anyone have test tones available or a good download for them?

I'm looking for some to aid in amp gain setting.

-10db 1Khz
-5db 40hz

etc...


Thanks


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## minbari (Mar 3, 2011)

Test Tones


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## asoggysponge (May 14, 2013)

Using Audacity, you can generate any tone you want, and subsequently adjust the gain of the tone.


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## miniSQ (Aug 4, 2009)

i was under the impression that gain setting test tones should be a 0db?

I use the cleansweep CD from JL audio 50hz and 1000hz.


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## minbari (Mar 3, 2011)

miniSQ said:


> *i was under the impression that gain setting test tones should be a 0db?*
> 
> I use the cleansweep CD from JL audio 50hz and 1000hz.


alot of wasted power that way. setting gains at -10 to -15 will give you much more range on the volume knob.


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## metanium (Feb 2, 2007)

miniSQ said:


> i was under the impression that gain setting test tones should be a 0db?
> 
> I use the cleansweep CD from JL audio 50hz and 1000hz.


Using tones at levels less than 0dB, allows for gain overlap. As a rule, the following applies:

0 dB Overlap	No-clipping, but good amount of power unused	+/- 0.1% THD
5 dB Overlap	Minor, inaudible clipping (Good compromise)	+/- 0.3% THD
10 dB Overlap	Clipping is audible (Max. overlap to set gain)	+/- 1.0% THD
15 dB Overlap	Noticeable clipping is present	+/- 10% THD


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## miniSQ (Aug 4, 2009)

minbari said:


> alot of wasted power that way. setting gains at -10 to -15 will give you much more range on the volume knob.


so that explains why when i set my gains according to JL's specs that i am finding i need to turn my volume knob up to almost max to get it loud, and my subs sound too soft?


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## minbari (Mar 3, 2011)

very well could be. try setting it with a -10 tone and see if that helps. (or just turn up the master gain to 10db more than it is  )


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## .69077 (Aug 24, 2013)

I too used the cleansweep cd to set the gains on my HD. Im gonna install an MS8 tomorrow so I guess its a moot point now.


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## miniSQ (Aug 4, 2009)

minbari said:


> very well could be. try setting it with a -10 tone and see if that helps. (or just turn up the master gain to 10db more than it is  )


genius


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## captainobvious (Mar 11, 2006)

minbari said:


> Test Tones


Thanks Minbari. I actually have the standard version of the normal tones. I'm looking for -10db and -5db versions for gain setting though.


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## minbari (Mar 3, 2011)

captainobvious said:


> Thanks Minbari. I actually have the standard version of the normal tones. I'm looking for -10db and -5db versions for gain setting though.


take the standard tones with your volume set for 3/4 (or whatever). measure SPL, then turn the volume down till it is 10db less.

set your gains, done!


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## captainobvious (Mar 11, 2006)

asoggysponge said:


> Using Audacity, you can generate any tone you want, and subsequently adjust the gain of the tone.



How might I go about making a -10db 1K tone and saving it as a -10db 1K tone...?

I see the generator option and select a 1K tone, but I don't hear it playing when I hit the play...?


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## captainobvious (Mar 11, 2006)

minbari said:


> take the standard tones with your volume set for 3/4 (or whatever). measure SPL, then turn the volume down till it is 10db less.
> 
> set your gains, done!


I've already measured all of the outputs on my P99RS twice with tones from 20hz all the way up to 20Khz and the deck doesn't clip even at max volume.

Doing your method puts the speakers at risk... I have an Oscope and want to set this up properly at the amp, measuring for clipping with -10db 1K tones for highs and mids and with -5db 40hz tones for midbass/subs. I was wanting to use the CD as source to keep all things consistent, but I'm not finding an easy way to create the tones needed and burn to a disc. I may end up having to just use the aux input combined with my laptop out and TrueRTA's built in generator I guess...?


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## captainobvious (Mar 11, 2006)

I think what I'm looking for is Autosound 2000 disc 4. Looks like exactly what I need.

Does anyone have a copy?


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## captainobvious (Mar 11, 2006)

Found EXACTLY what I was looking for right here:

http://www.diymobileaudio.com/forum...dio-discussion/129259-autosound-2000-cds.html

THANKS!


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## Jagged Corn Flakes (Sep 10, 2013)

Most higher end head units these days can be ran to full volume with NO clipping at the outputs. Using your full volume knob gives tremendous results.

I use a 0db track when setting gains and usually go about 10-20 watts or so below clipping on the scope.

I have found that running amps right up to before clipping will give you the absolute most power, but will not sound the best at full volume on the head unit. An amp usually sounds like it's running out of steam and loses some control right before clipping. This can be avoided by leaving a little "headroom" on the gain knob.

I know people are basically stating to go over clipping by running a -db tone. I disagree.


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## ATOMICTECH62 (Jan 24, 2009)

Always set HU and all signal processors,EQ's,crossovers and anything else in the signal chain before the amps at -0db so there will be no premature clipping,then set the amps at -5,-10 whatever works in your system for increased head room.


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## captainobvious (Mar 11, 2006)

ATOMICTECH62 said:


> Always set HU and all signal processors,EQ's,crossovers and anything else in the signal chain before the amps at -0db so there will be no premature clipping,then set the amps at -5,-10 whatever works in your system for increased head room.


Yep, that's the plan


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## minbari (Mar 3, 2011)

captainobvious said:


> I've already measured all of the outputs on my P99RS twice with tones from 20hz all the way up to 20Khz and the deck doesn't clip even at max volume.
> 
> *Doing your method puts the speakers at risk... *I have an Oscope and want to set this up properly at the amp, measuring for clipping with -10db 1K tones for highs and mids and with -5db 40hz tones for midbass/subs. I was wanting to use the CD as source to keep all things consistent, but I'm not finding an easy way to create the tones needed and burn to a disc. I may end up having to just use the aux input combined with my laptop out and TrueRTA's built in generator I guess...?


how so? 

What is the difference if you play a CD with a -10db track at full volume on the HU or turn the HU down 10db from the max volume with a 0db track? the end result is the HU is putting out 10db less than maximum. it really doesnt matter.


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## TOOSTUBBORN2FAIL (Jan 31, 2011)

Captain, did you check the sub channel? My p99 clipped at 62 on the sub channel pretty ugly, no clipping at 61. All other channels were fine at 62.


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## Jagged Corn Flakes (Sep 10, 2013)

minbari said:


> how so?
> 
> What is the difference if you play a CD with a -10db track at full volume on the HU or turn the HU down 10db from the max volume with a 0db track? the end result is the HU is putting out 10db less than maximum. it really doesnt matter.


Or you could just do it the right way by playing a zero db track at max volume on the headunit and then set the gains anywhere you please below clipping. Why make it so hard?


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## minbari (Mar 3, 2011)

Jagged Corn Flakes said:


> Or you could just do it the right way by playing a zero db track at max volume on the headunit and then set the gains anywhere you please below clipping. Why make it so hard?


because unless you have 3-400 watts per channel that method is not going to use all the power very often. CDs, MP3s, etc are not recorded at 0db and people dont listen to systems with the volume on max most of the time.

Its will waste more than half your power and not get very loud. no sensible installer would set gains this way unless you have alot of power to waste.


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## Jagged Corn Flakes (Sep 10, 2013)

minbari said:


> because unless you have 3-400 watts per channel that method is not going to use all the power very often. CDs, MP3s, etc are not recorded at 0db and people dont listen to systems with the volume on max most of the time.
> 
> Its will waste more than half your power and not get very loud. no sensible installer would set gains this way unless you have alot of power to waste.


This is one of the dumbest things I have ever heard. So turn the volume knob up. No matter how you set it, you aren't using most of your power most of the time anyway.


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## SoundChaser (Apr 3, 2009)

minbari said:


> because unless you have 3-400 watts per channel that method is not going to use all the power very often. CDs, MP3s, etc are not recorded at 0db and people dont listen to systems with the volume on max most of the time.
> 
> Its will waste more than half your power and not get very loud. no sensible installer would set gains this way unless you have alot of power to waste.


I totally agree… Plus, a little clipping once in a while here and there will not harm anything.


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## SoundChaser (Apr 3, 2009)

Jagged Corn Flakes said:


> This is one of the dumbest things I have ever heard. So turn the volume knob up. No matter how you set it, you aren't using most of your power most of the time anyway.


The volume knob goes passed max?


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## Jagged Corn Flakes (Sep 10, 2013)

SoundChaser said:


> The volume knob goes passed max?


Read the thread guy; not one post.


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## SoundChaser (Apr 3, 2009)

Jagged Corn Flakes said:


> Read the thread guy; not one post.


I did read the thread..

“Or you could just do it the right way by playing a zero db track at max volume on the headunit and then set the gains anywhere you please below clipping. Why make it so hard?”

If I set my gains this way I would not only be at max volume on the HU most of the time but would need to go passed max for my listening pleasure. 

I used 0db @ ¾ volume and still found certain material that needed max volume out of the head unit. Now I use a 0db signal with ½ volume on HU to set gains.


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## minbari (Mar 3, 2011)

SoundChaser said:


> I did read the thread..
> 
> “Or you could just do it the right way by playing a zero db track at max volume on the headunit and then set the gains anywhere you please below clipping. Why make it so hard?”
> 
> ...


agreed! it is the same mentality as using a -10db test tone for setting at 3/4 volume. however you get there, you dont want to set it up at 0db with max HU volume. (as you found out)


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## Jagged Corn Flakes (Sep 10, 2013)

SoundChaser said:


> I did read the thread..
> 
> “Or you could just do it the right way by playing a zero db track at max volume on the headunit and then set the gains anywhere you please below clipping. Why make it so hard?”
> 
> ...


Then you lose dynamics and SNR on material that was recorded properly by not using all the voltage your head unit has to give. Not to mention, you are most likely listening to a clipped signal most times.

Either way. If this method suits you, stick with it.


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## BuickGN (May 29, 2009)

Jagged Corn Flakes said:


> This is one of the dumbest things I have ever heard. So turn the volume knob up. No matter how you set it, you aren't using most of your power most of the time anyway.


Still making personal attacks because you don't understand something I see. Someone help this guy, he's going to run out of personal attacks before the day is over. Maybe a car audio tutor? Or maybe a filter for the keyboard. If only there was something upstairs that could filter what you think to what makes it to the keyboard lol.


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## minbari (Mar 3, 2011)

Jagged Corn Flakes said:


> Then you lose dynamics and SNR on material that was recorded properly by not using all the voltage your head unit has to give. Not to mention, you are most likely listening to a clipped signal most times.
> 
> Either way. If this method suits you, stick with it.



The dynamics are in the music, doesnt really matter if the volume knob is 1/2, 3/4, whatever. as long as you are not having to max the volume knob and start clipping the HU. to say I dont get as good dynamics if I dont max my HU out is just nonsense.

SNR is just that! a ratio. If you have 100db SNR, then you have 100 db of signal for every 1db of noise. Doesnt matter if you have the volume set to 1/16 volume or 15/16 volume, the ratio remains the same. most SNR is soo high you couldnt possibly hear it anyway.

not trying to attack you, but what kind of back ground do you have in electronics?


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## Jagged Corn Flakes (Sep 10, 2013)

minbari said:


> The dynamics are in the music, doesnt really matter if the volume knob is 1/2, 3/4, whatever. as long as you are not having to max the volume knob and start clipping the HU. to say I dont get as good dynamics if I dont max my HU out is just nonsense.


So as long as the dynamics are in the music, you can use any equipment you want, set at any volume level, etc., and get the same amount of dynamic sound. Come on, guy. This is getting all too funny now.

You get better dynamics at all levels, not just max volume. As stated, if the other way suits you, then stick with it.

Good head units don't clip at max volume.


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## minbari (Mar 3, 2011)

Jagged Corn Flakes said:


> So as long as the dynamics are in the music, you can use any equipment you want, set at any volume level, etc., and get the same amount of dynamic sound. Come on, guy. This is getting all too funny now.
> 
> You get better dynamics at all levels, not just max volume. As stated, if the other way suits you, then stick with it.
> 
> Good head units don't clip at max volume.


where would the dynamics be exactly? your gear cant put dynamics in music that isnt there to begin with.


not going to comment on the rest of my post?


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## Kriszilla (Jul 1, 2013)

Jagged Corn Flakes said:


> Then you lose dynamics and SNR on material that was recorded properly by not using all the voltage your head unit has to give. Not to mention, you are most likely listening to a clipped signal most times.
> 
> Either way. If this method suits you, stick with it.


Holy hell... My electrical theory professor would have had a field day with this one...


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## HiloDB1 (Feb 25, 2011)

:lurk:


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## neo_styles (Oct 18, 2012)

Seems like this topic never has a right answer. And isn't this all dependent on the type of music that will be listened to? Hip Hop, Drum & Bass, pipe organ music, and gregorian chants are going to have a different threshold to clipping than, say, smooth jazz and classic rock.

I was always raised in the school of thought that you set your dB overlap based on where you fit into the musical spectrum of taste. I most certainly wouldn't recommend a -10 tone to someone who will listen to music that is essentially poorly-mastered, compressed beyond all recognition, and already recorded at or near clipping. It's just a recipe for disaster. That being said, I HAVE been in the camp of using a 0dB tone on speakers and a -5dB tone on subs for a little extra oomph (I can always use sub level at the HU to attenuate). Seeing as how I'm changing decks this weekend, I'll revisit the concept and probably adopt a -3 or -6dB tone for setting gains the next time around.

Furthermore, who here has the listening threshold to keep their volume maxed out with gains set like this? Even at 0dB, I need windows down and no passengers to even THINK about playing music up where my gains were set. If I set gains at lower than 75% volume, I also have a lower volume level for comfortable listening (example: setting at 35/40 results in listening levels of 15-18/40, setting at 25/40 only requires a 7-9/40). This leads me to think it's more of finding a happy medium than one standard rule.

Also (and I know this is going to invite some flaming), look into how instructions for the infamous DD-1 are outlined. You set max HU volume before clipping at 0dB, speaker volume at -5dB, and sub volume at -10 or -15. Just seems horrible in practice. So where are the standards and relevant proof substantiating the claims here?


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## BuickGN (May 29, 2009)

You guys don't even want to know how I set mine lol.

I take the lowest SPL speakers which happen to be my midbass and set those to the max without clipping with the stock HU at 30 out of 40, 0db, since it starts lowering the bass pretty badly after that. I can take it to the full 40 out of 40 without much clipping so I have a big margin for error. Once I have the first set of speakers setup, I level match the rest to them. It's worked well so far. I have MB300x2, MR150x2, TW150x2, and SUB500x1 (250x2). The speakers that get the most power are the weakest ones ironically. I have no clipping on any other channel even at 40 out of 40. 20 is the highest I ever go unless someone wants a demo. That works well because the HU is not altering the FR much at normal loud listening levels and by the time I get into a range where it starts it's EQ thing it's far beyond any sound quality style listening. It seems as I've gotten more and more headroom in the system I've been a lot "sloppier" about setting the gains.


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## captainobvious (Mar 11, 2006)

minbari said:


> how so?
> 
> What is the difference if you play a CD with a -10db track at full volume on the HU or turn the HU down 10db from the max volume with a 0db track? the end result is the HU is putting out 10db less than maximum. it really doesnt matter.



Because the speakers are playing high duty tones. If your head unit clips, your putting your speakers at risk at high volume. Why not just disconnect the speaker wires and then use the oscilloscope right at the amplifier outputs? First you have to determine the point at which your head unit begins to clip, then that becomes your "maximum" volume you shouldn't turn it past. Set it there, then run the -10db tone and measure with the o-scope at the amp outputs and adjust gain until just before clipping.

That's how I thought it was supposed to be done? 

EDIT: Also, I'd probably be more inclined to do -5db on highs/mids and -10db on midbass/subs (had that reversed earlier on in the thread). Clipping at the sub level is probably less disturbing than in the vocal range. That, and my mids/tweeters are fairly efficient as it sits so they don't need too much of a boost.




TOOSTUBBORN2FAIL said:


> Captain, did you check the sub channel? My p99 clipped at 62 on the sub channel pretty ugly, no clipping at 61. All other channels were fine at 62.


Oh , and BTW I was wrong, my P99RS DOES in fact clip, on *one* of the outputs (left mid) at 59/62 on the volume knob :surprised:
*Output Voltage at volume*
High Left 3.43 at 58 
High Right 2.73 at 58 
Mid Left 4.89 at 58vol clips at 59 at 1k 
Mid Right 4.37 at 58 
Low Left 2.48 at 58 
Low Right 3.5 at 58 
Sub Left 1.24 at 58 
Sub Right 2.20 at 58


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## minbari (Mar 3, 2011)

captainobvious said:


> Because the speakers are playing high duty tones. If your head unit clips, your putting your speakers at risk at high volume. Why not just disconnect the speaker wires and then use the oscilloscope right at the amplifier outputs? First you have to determine the point at which your head unit begins to clip, then that becomes your "maximum" volume you shouldn't turn it past. Set it there, then run the -10db tone and measure with the o-scope at the amp outputs and adjust gain until just before clipping.


I never said that the speakers _had_ to be connected. you can definitely do it this way.

either way you do it, you are gonna wanna set up your gain structure for clipping or you will never get all the wattage out of your amplifiers that you paid for. 

contrary to popular believe, clipping doesnt hurt speakers. A speaker doesnt know the difference between a squarewave and a sinewave. Its all about power and while it is true that a full squarewave is 2x the power of a sinewave, how often do you listen to your system flat out?


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## captainobvious (Mar 11, 2006)

minbari said:


> I never said that the speakers _had_ to be connected. you can definitely do it this way.
> 
> either way you do it, you are gonna wanna set up your gain structure for clipping or you will never get all the wattage out of your amplifiers that you paid for.
> 
> contrary to popular believe, clipping doesnt hurt speakers. A speaker doesnt know the difference between a squarewave and a sinewave. Its all about power and while it is true that a full squarewave is 2x the power of a sinewave, how often do you listen to your system flat out?



I guess I misunderstood your post then. When you said "measure SPL" I thought this is the method you were prescribing 
Agreed on the sine wave thing as well. That's a benefit of setting gain _using_ the sine wave actually. 

Can you elaborate on the clipping not hurting speakers thing? I've always heard/read the opposite.

Thanks


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## minbari (Mar 3, 2011)

captainobvious said:


> I guess I misunderstood your post then. When you said "measure SPL" I thought this is the method you were prescribing
> Agreed on the sine wave thing as well. That's a benefit of setting gain _using_ the sine wave actually.
> 
> Can you elaborate on the clipping not hurting speakers thing? I've always heard/read the opposite.
> ...


its all AC, a speaker just goes back and forth. weather it is music, pure sine wave or squarewave, the speaker just goes back and forth. as long as you are not exceeding mechanical or thermal limits, the speaker will be just fine. 

Mechanical is easy. once it starts making funny noises, you went too far 

For thermal you just have to look at what the speaker can handle. If it is rated for 250 watts RMS, then it will handle 250watts of heat and not be damaged. would it matter if that heat comes from 250 watts of a sinewave or 250 watts of a squarewave? watts are watts. The speaker doesnt know the difference, its just heat.


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## captainobvious (Mar 11, 2006)

minbari said:


> its all AC, a speaker just goes back and forth. weather it is music, pure sine wave or squarewave, the speaker just goes back and forth. as long as you are not exceeding mechanical or thermal limits, the speaker will be just fine.
> 
> Mechanical is easy. once it starts making funny noises, you went too far
> 
> For thermal you just have to look at what the speaker can handle. If it is rated for 250 watts RMS, then it will handle 250watts of heat and not be damaged. would it matter if that heat comes from 250 watts of a sinewave or 250 watts of a squarewave? watts are watts. The speaker doesnt know the difference, its just heat.


Yes but the big difference between music and a sine wave is that music is dynamic with varying frequency and intensity, whereas a pure sine wave is not. You're senidng a stronger signal, more consistently by using a sine wave vs music. IE- with music you're not baking the driver with a constant wattage, no?
The problem is that once you reach a thermal or mechanical limit, it *may* already be too late. Some drivers are far more sensitive to this than others (think planars and ribbons).


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## Mic10is (Aug 20, 2007)

disconnect speakers from amps when doing this


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## minbari (Mar 3, 2011)

captainobvious said:


> Yes but the big difference between music and a sine wave is that music is dynamic with varying frequency and intensity, whereas a pure sine wave is not. You're senidng a stronger signal, more consistently by using a sine wave vs music. IE- with music you're not baking the driver with a constant wattage, no?


absolutely, which is why you want your speakers rated for RMS or avg power. Again, does it matter if i play music at a level that the avg power is 250 watts or a sine wave that the avg power is 250 watts? Granted it will take less to get to that 250 watts with a sinewave.(as you mentioned, it is a constant tone, vs a dynamic nature of music) But assuming you dont ever hit mechanical limits, 250 watts is 250 watts. ( in reality you will almost always hit mechanical limits with music before thermal.)


> The problem is that once you reach a thermal or mechanical limit, it *may* already be too late. Some drivers are far more sensitive to this than others (think planars and ribbons).


yup, you have to know your gears limitations. some speakers are more forgiving than others.


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## captainobvious (Mar 11, 2006)

Mic10is said:


> disconnect speakers from amps when doing this



I did when I just did this a couple days ago. I started off with 0db tones first and adjusted amp output to just below clipping (I had previously had amp gains at minimum). That already made a significant difference in the available output. I think -5db should give me more output than I will ever need.


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## Jagged Corn Flakes (Sep 10, 2013)

captainobvious said:


> I did when I just did this a couple days ago. I started off with 0db tones first and adjusted amp output to just below clipping (I had previously had amp gains at minimum). That already made a significant difference in the available output. I think -5db should give me more output than I will ever need.


And more clipping than you'll ever need too at those last few clicks on the volume knob. Woo hoo!


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## ErinH (Feb 14, 2007)

Jagged Corn Flakes said:


> And more clipping than you'll ever need too at those last few clicks on the volume knob. Woo hoo!


Don't turn up the volume louder than is reasonable. 

Gain knobs (which is what a volume knob can also be inside red) aren't all or nothing.


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## Earzbleed (Feb 10, 2013)

Jagged Corn Flakes

Banned
Aww, bugger. I enjoyed reading his rants.


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## cleansoundz (May 14, 2008)

Great information.


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## mirko88 (Aug 26, 2014)

Great info in this thread.

My preferred method to set gains is to establish maximum output level on the HU with a scope and test track at 0dB.
At that maximum level on the HU I play the 0dB test tone and with the scope, set the gain on the amp just below clipping.
I write the output voltage down.

Then I play the -5dB test tone with HU at max unclipped level and set the gain on the amp again to the same output voltage as recorded in the previous step. 

Now, my question is this, because I lack the technical knowledge:
If I add a sound processor, like the RF 3Sixty.2 into the equasion. I generally would want to control all system settings on the sound processor. I would still determine the max unclipped levels for each component, including the 3Sixty. But for achieving system balance between front, back and sub, I likely attenuate 1 or 2 channels. What does that actually do besides attenuation?
Do I loose dynamic range or output power of the amp because I turn down the output level of the 3Sixty?
Should I have any concerns on being 'sub-optimal' when applying attenuation for system balance?


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