# Setting the amplifier gain higher makes the amplifier work harder



## trumpet (Nov 14, 2010)

"*Setting the amplifier gain higher makes the amplifier work harder*"

I hear this statement all the time and I'm tired of not knowing for a fact if this is true or false. Usually it goes like this in a discussion: "You want the strongest input voltage for the amp so you can set the gain lower, and this makes the amp not have to work as hard."

The way I understand it is the gain is merely an adjustment to get the amplifier on the same level as the input voltage to avoid clipping. A properly set gain will have the amplifier operating as intended, regardless of how far the knob is twisted left or right.

Am I missing something here?


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## Spyke (Apr 20, 2012)

That's basically it. The best way to do it is to find out where the signal from your hu starts to clip. Most good hu's will be able to go to full volume without clipping. So if your 4v preouts can actually put out 4v after traveling through 16+ feet of rca cable (which I doubt) then you would set the amp gain to 4v. There is always some signal loss in the rca's though. This is why quality rca's are a must. On top of that you would want to set your amp gains with an o-scope but most people don't have one so you could improvise with a dmm which is really frowned upon by some but has always worked for me. Most music is recorded at a lower level so using a 0db test tone may not give the volume that you are looking for which is why some people use a -5db tone to set gains. I use a line driver is one of my systems and that allows me to keep the gain on the sub amp at absolute 0. It keeps noise to a minimum while making the bass deeper and more dynamic. So the line driver is doing the work amplifying the signal and there for the sub needs to work a lot less. Hope this helps.


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## trumpet (Nov 14, 2010)

I'm with you except for a couple of points. RCAs will have an almost negligible voltage drop over a 16 ft run. That would be the least of my concerns for picking a good RCA. It's a low current signal and even your most basic RCAs will transmit the signal adequately. I've demonstrated that countless times to know that it's more important to keep the RCA away from obvious sources of radiated RF energy. In my personal system I use RCAs that I scavenged from boxes of old gear pulled out of customer vehicles. These are nothing more than 2 pairs of jacketed 24 gauge wires surrounded by a metal braid; very old school and no mystery marketing BS. I would have pulled them out instantly if I felt they were a weak point.

The second issue I disagree on is that a line driver results indirectly in making the sub work less. The sub is going to do what it does according to the AC voltage coming out of the amp. Whether you get that voltage from an 8V input or a 4V input, the sub is doing the same amount of work. The voice coil might in theory take on a little more energy due to distortion at the lower voltage(this coming from the gain adjusted higher), but the cone is going to move the same amount.


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## SoundChaser (Apr 3, 2009)

trumpet said:


> "*Setting the amplifier gain higher makes the amplifier work harder*"
> 
> I hear this statement all the time and I'm tired of not knowing for a fact if this is true or false. Usually it goes like this in a discussion: "You want the strongest input voltage for the amp so you can set the gain lower, and this makes the amp not have to work as hard."
> 
> ...


If the goal is and it should be, to set a specific output voltage / power from an amplifier then a 4v deck verses a 2v deck will not make the amp work any harder.

For instance, you’re setting the output of the amp to 25v. Using the 2v deck the gains are set to ¾ max. Using the 4v deck you achieve the same 25v but the gains are only set to ¼ max. Your amp is working just as hard with either deck.


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## envisionelec (Dec 14, 2005)

I posted something in a similar thread.

http://www.diymobileaudio.com/forum/1316593-post26.html

Cranking the amp gain to max makes it work harder _faster. _Meaning, it doesn't take many steps (or turns) on the ol' volume control to reach full output.

By the way, a clipping amplifier is more efficient - so it's actually working more efficiently while you cook your speakers.


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## minbari (Mar 3, 2011)

If the amp put out 100w, then it puts out 100w. Where the gains are set have no bearing on what out will put out. It only has to do with when it will do it on the volume knob.

Sent from my Motorola Electrify using Tapatalk 2


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## Spyke (Apr 20, 2012)

trumpet said:


> I'm with you except for a couple of points. RCAs will have an almost negligible voltage drop over a 16 ft run. That would be the least of my concerns for picking a good RCA. It's a low current signal and even your most basic RCAs will transmit the signal adequately. I've demonstrated that countless times to know that it's more important to keep the RCA away from obvious sources of radiated RF energy. In my personal system I use RCAs that I scavenged from boxes of old gear pulled out of customer vehicles. These are nothing more than 2 pairs of jacketed 24 gauge wires surrounded by a metal braid; very old school and no mystery marketing BS. I would have pulled them out instantly if I felt they were a weak point.
> 
> The second issue I disagree on is that a line driver results indirectly in making the sub work less. The sub is going to do what it does according to the AC voltage coming out of the amp. Whether you get that voltage from an 8V input or a 4V input, the sub is doing the same amount of work. The voice coil might in theory take on a little more energy due to distortion at the lower voltage(this coming from the gain adjusted higher), but the cone is going to move the same amount.


Rca's can have an impact on signal transmission. And that's just it, it's a low level signal traveling down a long run of thin wire. If the copper is impure or the connectors aren't very good it will add resistance to the signal. I'm not talking about dropping the voltage by 50% or anything but maybe .2-.5 volts. Why lose that if you don't have to. It's getting to the geeky point but it is true. 

Damn my mistake on that. I meant the sub amplifier has to do less work. Thanks for catching that.


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## Spyke (Apr 20, 2012)

minbari said:


> If the amp put out 100w, then it puts out 100w. Where the gains are set have no bearing on what out will put out. It only has to do with when it will do it on the volume knob.
> 
> Sent from my Motorola Electrify using Tapatalk 2


That's not entirely true. I'll bet I could get my 500w rockford to put out 10,000 watts at 99% thd. If i cranked the gains up and applied a 30v input signal. How do you think those companies that sell 5,000 watt amps for 100 bucks get their "max" power ratings?


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## minbari (Mar 3, 2011)

Spyke said:


> That's not entirely true. I'll bet I could get my 500w rockford to put out 10,000 watts at 99% thd. If i cranked the gains up and applied a 30v input signal. How do you think those companies that sell 5,000 watt amps for 100 bucks get their "max" power ratings?


Good luck with that. I understand you're point (even if it was grossly overstated) but my point is still valid. For a given wattage and thd,etc. Where the gain is doesn't matter. You will just have less volume knob range if it is set too high

Sent from my Motorola Electrify using Tapatalk 2


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## Spyke (Apr 20, 2012)

minbari said:


> Good luck with that. I understand you're point (even if it was grossly overstated) but my point is still valid. For a given wattage and thd,etc. Where the gain is doesn't matter. You will just have less volume knob range if it is set too high
> 
> Sent from my Motorola Electrify using Tapatalk 2


LOL. Yeah maybe a little exaggerated. I get your point I was just being a smart ass. :laugh:


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## envisionelec (Dec 14, 2005)

Spyke said:


> Rca's can have an impact on signal transmission. And that's just it, it's a low level signal traveling down a long run of thin wire. If the copper is impure or the connectors aren't very good it will add resistance to the signal. I'm not talking about dropping the voltage by 50% or anything but maybe .2-.5 volts. Why lose that if you don't have to. It's getting to the geeky point but it is true.
> 
> Damn my mistake on that. I meant the sub amplifier has to do less work. Thanks for catching that.


That's *not* true at all. 

Say the input impedance of the amplifier is rather low at 10k ohm. The RCA cable would have to insert 10k ohms of resistance to drop the voltage level by half. To drop a 2V signal by 0.5V, you'd need ~3,330 ohms of resistance. Unless the cable was faulty, this isn't happening.


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## envisionelec (Dec 14, 2005)

Spyke said:


> That's not entirely true. I'll bet I could get my 500w rockford to put out 10,000 watts at 99% thd. If i cranked the gains up and applied a 30v input signal. How do you think those companies that sell 5,000 watt amps for 100 bucks get their "max" power ratings?


They don't rate them; they just lie. A 500W amp will put out 500W at 99% THD. Power output doesn't go up with THD, quite the opposite. 

Besides, distortion doesn't blow speakers. Duty cycle does. Moving on...


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## minbari (Mar 3, 2011)

envisionelec said:


> That's *not* true at all.
> 
> Say the input impedance of the amplifier is rather low at 10k ohm. The RCA cable would have to insert 10k ohms of resistance to drop the voltage level by half. To drop a 2V signal by 0.5V, you'd need ~3,330 ohms of resistance. Unless the cable was faulty, this isn't happening.


and even if it did (which it wouldn't) bump the gain by a hair and problem solved.


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## Spyke (Apr 20, 2012)

envisionelec said:


> That's *not* true at all.
> 
> Say the input impedance of the amplifier is rather low at 10k ohm. The RCA cable would have to insert 10k ohms of resistance to drop the voltage level by half. To drop a 2V signal by 0.5V, you'd need ~3,330 ohms of resistance. Unless the cable was faulty, this isn't happening.


All wire has resistance. I am not talking about input impedance. I am talking about the voltage that is lost when traveling from point a "the source" to point b "the amplifier". Not much and prob won't make a huge difference but it is true.


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## minbari (Mar 3, 2011)

Spyke said:


> All wire has resistance. I am not talking about input impedance. I am talking about the voltage that is lost when traveling from point a "the source" to point b "the amplifier". Not much and prob won't make a huge difference but it is true.


we know what you are talking about...........and you wont get a voltage drop without current. take a 1million ohm resistor and touch one end to your car battery. then measure the voltage at the other end...............pretty much the same huh? no current = no voltage drop......this is also why you cant measure voltage drop on an amplifier power wire unless you are running it flat out. there will be no voltage drop on the power cables with no current traveling on them.

since the input impedance of an amplifier is 10-20k ohms the amount of current traveling is nearly nothing. you could have cheap RCAs with 33ga wire, it still wont drop any voltage.


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## MarkZ (Dec 5, 2005)

Yikes. Spyke, you need to quit while you're ahead.


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## minbari (Mar 3, 2011)

MarkZ said:


> Yikes. Spyke, you need to quit while you're ahead.


Quit while he its behind 

Sent from my Motorola Electrify using Tapatalk 2


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## Spyke (Apr 20, 2012)

Damn it. I just tested it. I must have been doing something wrong or with bad cables the last time I did that. O well, At least I learned something.


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## MarkZ (Dec 5, 2005)

Spyke said:


> Damn it. I just tested it. I must have been doing something wrong or with bad cables the last time I did that. O well, At least I learned something.


:thumbsup:


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## envisionelec (Dec 14, 2005)

minbari said:


> and even if it did (which it wouldn't) bump the gain by a hair and problem solved.


Yes, exactly. 

Spyke - everyone has something to learn. No problem. Thanks for not running off the rails.  If you've got cheap RCAs that get pinched/shorted, that's a totally different problem and absolutely will cause problems. Thin RCA cables aren't good for auto installs because of the harsh physical environment.


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## nitrofish72 (Jul 21, 2009)

minbari said:


> Good luck with that. I understand you're point (even if it was grossly overstated) but my point is still valid. For a given wattage and thd,etc. Where the gain is doesn't matter. You will just have less volume knob range if it is set too high
> 
> Sent from my Motorola Electrify using Tapatalk 2


What he said.


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## TrickyRicky (Apr 5, 2009)

This is just my thoughts, but if you do have a HV head unit that means your gain on your amplifier will more than likely be all the way counterclockwise (towards the 2v-5v setting) if your head unit is less than 2v then the gain will be more towards the clockwise (2v-.2v setting). 

Either way you will end up with the same amount of output (amplified signal) from the amplifier.....CORRECT OR WRONG? Having a HV head unit will not make your amplifier have HIGHER OUTPUT, the amplifier will still have its limits.

The thing is a lot of people think of the gain as a volume control, so they think if I go higher (towards the .2v setting) my amp will put out more power----- WRONG it will clip the output singal and damage several things.

If am wrong please correct me.


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## ShutterX (May 14, 2012)

hi folks,

just read thru the thread and learned a lot. thanks to the pros for that. iam more or less noob here, so still need some clarification.

1) i have a 500wrms @ 2ohm mono. its cea 2006 rated. does this mean it will always provide this kinda power? (provided i match gains with input voltage using a dmm)

2) some was saying, 'this amp will produce 500wrms @2ohm no matter where the gain settings are'

if this is true, how come i can use my 300w woofer with this system? what i generally do is set hu volume just below clipping point and set voltage to what ever would correspond to 350wrms and leave it there. iam i doing anything wrong?

cheers


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## t3sn4f2 (Jan 3, 2007)

ShutterX said:


> hi folks,
> 
> just read thru the thread and learned a lot. thanks to the pros for that. iam more or less noob here, so still need some clarification.
> 
> ...


1- Yes it will put out 500 watts when the input signal level and gain setting ask it to.

2- That's a true statement but it needs to be qualified by saying that it will put out that power IF the input voltage corresponds to the gain setting you have the amp set to. IE counter clockwise at say ~5 volts will put out the rated power IF you input signal is ~5 volts. Turn the gain up to .3 volts and all you need then is .3 volts of input voltage. So yes "it will put out rated power no matter the gain setting"

(This is also assuming the amp works as it should and does put out rated power at its labeled gain settings)


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## Spyke (Apr 20, 2012)

TrickyRicky said:


> This is just my thoughts, but if you do have a HV head unit that means your gain on your amplifier will more than likely be all the way counterclockwise (towards the 2v-5v setting) if your head unit is less than 2v then the gain will be more towards the clockwise (2v-.2v setting).


Yes.



TrickyRicky said:


> Either way you will end up with the same amount of output (amplified signal) from the amplifier.....CORRECT OR WRONG? Having a HV head unit will not make your amplifier have HIGHER OUTPUT, the amplifier will still have its limits.


Correct



TrickyRicky said:


> The thing is a lot of people think of the gain as a volume control, so they think if I go higher (towards the .2v setting) my amp will put out more power----- WRONG it will clip the output singal and damage several things.
> 
> If am wrong please correct me.


I'm not sure about this. I agree that when you crank the gain up distortion will increase. What I don't know is if the power output from the amp will also increase. I imagine it would to a point though. When I set my gain and am looking for 40v, I can turn the gain up(just for demonstration purposes) and reach 100v which translates to 2500w. Way higher than the amp is rated for obviously. Also note that this is being done with the sub disconnected. I am not in anyway saying that you can or should increase gains to get more power out of your amp.


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## Spyke (Apr 20, 2012)

I also would like to point out that when I set my gains, I always use a -5db test tone. I do this because music is usually recorded at less than a 0db level. If you set the gains using a 0db tone and never exceed the hu level where you set the gains, your amp will not reach full output under most circumstances.


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## TrickyRicky (Apr 5, 2009)

Spyke said:


> I'm not sure about this. I agree that when you crank the gain up distortion will increase. What I don't know is if the power output from the amp will also increase. I imagine it would to a point though. When I set my gain and am looking for 40v, I can turn the gain up(just for demonstration purposes) and reach 100v which translates to 2500w. Way higher than the amp is rated for obviously. Also note that this is being done with the sub disconnected. I am not in anyway saying that you can or should increase gains to get more power out of your amp.


When you do this do you have a scope to see the signal? I know you stated with no load/speaker hooked up so how do you know that the 40v your seeing on your dmm is actually unclipped???

I can do the same and make any amplifier reach crazy voltages by just using my dmm and gain w/no load/speakers. That does not mean it can do it, because it might be beyond clipping.

What amplifier your using that can produce 100v.....unclipped (unless your reffering to peak-to-peak voltage)?


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## Spyke (Apr 20, 2012)

TrickyRicky said:


> When you do this do you have a scope to see the signal? I know you stated with no load/speaker hooked up so how do you know that the 40v your seeing on your dmm is actually unclipped???


Educated guess. Not everyone has a scope.


TrickyRicky said:


> I can do the same and make any amplifier reach crazy voltages by just using my dmm and gain w/no load/speakers. That does not mean it can do it, because it might be beyond clipping.


It *might* be? 2500w from a 500w rms amp and it *might* be clipping?


TrickyRicky said:


> What amplifier your using that can produce 100v.....unclipped (unless your reffering to peak-to-peak voltage)?


Not saying that a 500w amp will produce 2500 clean watts. Just stating that it produces *unloaded* voltage that correlates to some really high wattage figures. Maybe loaded would be a different story.


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## t3sn4f2 (Jan 3, 2007)

Spyke said:


> Not saying that a 500w amp will produce 2500 clean watts. Just stating that it produces *unloaded* voltage that correlates to some really high wattage figures. Maybe loaded would be a different story.


Maybe.


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## TrickyRicky (Apr 5, 2009)

Spyke said:


> Educated guess. Not everyone has a scope.
> 
> 
> It *might* be? 2500w from a 500w rms amp and it *might* be clipping?
> ...


If your calculating power (rms/wattage) there are many formulas to use and different methods. From checking voltage and AC current will give you a good idea of actuall power. Another involves dummy loads (high wattage resistors), then there is the one where you use square root of 2. Keep in-mind the onboard fuses, if your 500watt amplifier has 60-80amperage of fuses then there is no way in heaven or hell that amplifier can or will produce anything near 2500watts.

Which one is more accurate, hell try all three if possible to get the most accurate rating.


There are many scopes, they range from 60.00 (handheld/digital) to 400.00 (used CRT scope/ Tek scopes). I have a OLD Tek 465 and it does a wonderful job and has very nice clean traces when compare to a handheld scope. Sinewaves on a handheld scope look all squiggly and not even curvy (sorta like trying to draw a curve on windows 90 paint program----NOT COOL).


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## Spyke (Apr 20, 2012)

Ok ok let's back up. Line 1. I was being sarcastic. I calculate power and set it according to voltage.

Line 2. Again, being sarcastic. Notice the boldface on the words might

Line 3. Reread and notice the boldface on the word unloaded.

Me and you are on the same page. I am in no way shape or form saying that you can get rediculous amounts of power by turning up the gains. I also think that setting gains using a scope is by far the safest and most accurate way to set gains. On the other hand, if you can get it in the ball park using a dmm and aren't stupid with the volume knob you won't have problems either. I have been doing this for 16 years and have never once blown an amp, sub, speaker, or tweeter.


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## chad (Jun 30, 2005)

you and I


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## TrickyRicky (Apr 5, 2009)

Spyke said:


> Ok ok let's back up. Line 1. I was being sarcastic. I calculate power and set it according to voltage.
> 
> Line 2. Again, being sarcastic. Notice the boldface on the words might
> 
> ...


Trust me I know you were being sarcastic, but the young fellas reading this will take it seriously. Before you know it everyone will do your way "formula" and come up with crazy numbers - you forgot to plug in AC current. Just throwing that out there.


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## Spyke (Apr 20, 2012)

TrickyRicky said:


> Trust me I know you were being sarcastic, but the young fellas reading this will take it seriously. Before you know it everyone will do your way "formula" and come up with crazy numbers - you forgot to plug in AC current. Just throwing that out there.


Yeah I should prob be more careful. There's enough bad info out there already.


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## Spyke (Apr 20, 2012)

chad said:


> you and I


Shut up Chad.


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## TrickyRicky (Apr 5, 2009)

Spyke said:


> Shut up Chad.


lol his a funny guy. I remember this joke he made about a post I made about a year or two (something to do with batteries and a dildo, still to this day I think about that joke every other time I get on DIYMA) lol.


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## Spyke (Apr 20, 2012)

Hey, since this is a grammar lesson now. What is the correct way to word this sentence?
1. My car needs to be washed
or
2. My car needs washed

I vote 1.


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## TrickyRicky (Apr 5, 2009)

Spyke said:


> Hey, since this is a grammar lesson now. What is the correct way to word this sentence?
> 1. My car needs to be washed
> or
> 2. My car needs washed
> ...


WTF even my 4year old knows which one. You probably meant "My car needs a washing" on #2, but thats just my guess.


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## Spyke (Apr 20, 2012)

TrickyRicky said:


> lol his a funny guy. I remember this joke he made about a post I made about a year or two (something to do with batteries and a dildo, still to this day I think about that joke every other time I get on DIYMA) lol.


Yeah he seems it. It was funny because of how random it was.


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## Spyke (Apr 20, 2012)

TrickyRicky said:


> WTF even my 4year old knows which one. You probably meant "My car needs a washing" on #2, but thats just my guess.


No seriously. That's the new way people are talking and I absolutely hate it. It's even been on the radio. "to be" is left out in sentences like that. I live on the east coast so maybe it's local. I got to go, my amp needs installed. aaaarrrrghhhh. hate it.


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## chad (Jun 30, 2005)

I define random.

I can make anything blush.


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## subwoofery (Nov 9, 2008)

TrickyRicky said:


> lol his a funny guy. I remember this joke he made about a post I made about a year or two (something to do with batteries and a dildo, still to this day I think about that joke every other time I get on DIYMA) lol.


Link?  

Kelvin


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## TrickyRicky (Apr 5, 2009)

subwoofery said:


> Link?
> 
> Kelvin


Its going to be impossible for me to find it, but maybe Chad can remember what thread it was. Darn it I didn't want to say it but heres how it went.

Me: "That gives me an idea" Wait I think it was on a forum dealing with an OLD SCHOOL german car audio competition youtube video, I think they had spinning woofer enclosures. Some weird crap thats when I made that coment....and Chad came out of no where :surprised: with the following...


Chad: "what.. put a 12v battery on your dildo" - or something like that, it was funny :laugh: as crap that I couldn't even get mad cause I was laughing so hard.


I hope someone can post a link am too lazy to find it, lol.


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## ShutterX (May 14, 2012)

t3sn4f2 said:


> 1- Yes it will put out 500 watts when the input signal level and gain setting ask it to.


i see. thanks. but what if we go over that point? is it sure to distort/clip thereafter?

cheers


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## t3sn4f2 (Jan 3, 2007)

ShutterX said:


> i see. thanks. but what if we go over that point? is it sure to distort/clip thereafter?
> 
> cheers


Depends. You can over drive gains by quite a bit before you begin to hear a difference. By as much as demanding twice the rated output (ie going from 5 volts to 2.5 volts or .5 to .25 on the gains). This is because music has an average demand of 5 times less power then the rated output of your amp, and the peaks that you will be over driving come and go too fast for you to detect whether they were 15dB or 12dB in amplitude (ie 3dB corresponds to twice the power increase). 

Music also has more energy in the bass and mid bass bands then the midrange and up. So the _compression_ of the output peaks tends to happen more so in the bass and mid bass bands in typical music. And since we are less sensitive to distortion in that range, you will notice the degradation even less. 

In the end you are if you don't push the gains too far, you are just doing a crude but effective form of the "dynamic range compression" used in modern LOUD tracks. Which in a noisy environment is accepted and probably needed.


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## wildnimal (Mar 29, 2008)

Ok Guys a simple question.

I have an ABC HU and XYZ Amp.

Lets suppose XYZ HU puts out 8 unclipped volts @ 50 volume (this is max volume). And ABC amp takes input from 8 to 0.2 v and puts out 100 x 4 W RMS.

Lets see XYZ HU gives 6volts @ 40 Volume and the gain pot on ABC amp is at 8 volts (lowest). Now i match the voltage to 6Volts. The speakers will get louder right ? As the voltage is matched. 

Now when i turn the Gains knob down why is there a drop in output / speakers are not loud ? Amp is still putting out 100 x 4 right ?


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## MarkZ (Dec 5, 2005)

Because the gain control IS a volume control. No, seriously. It's a potentiometer in a voltage divider circuit. We call that a volume knob. 

You turn it up, things get louder. You turn it down, things get softer. It doesn't add distortion, it doesn't make the amp work harder. Some of you guys are overthinking things.

Here's a diagram:

CD -> HU volume knob -> amp gain ctrl -> amplifier

The last stage ("amplifier") has a constant gain (let's say... x 10). It also has a maximum output. Manipulating the two volume controls in front of it allows you to achieve that maximum output. That maximum output never changes. Doesn't matter where any of the volume knobs are, or whether it's a head unit, ipod, or sine wave generator providing the input signal.

You can keep the HU volume knob at a fixed setting and go to your trunk and turn the gain knob to control volume, but that's a pain in the ass. So people usually keep the gain knob at a fixed setting and use the HU volume knob to control volume. Makes much more sense.

But make no mistake about it. It's a volume knob. I think when people begin to realize this, they'll have a much easier time understanding what they're doing when they turn that gain knob.


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## t3sn4f2 (Jan 3, 2007)

wildnimal said:


> Ok Guys a simple question.
> 
> I have an ABC HU and XYZ Amp.
> 
> ...


No, it's not putting out rated power then. It is putting out ~56 watts.

If you have the head unit set to 6 volts out and you move (ie lower) the gain from 6 volts to 8 volts it will lower the output because you are setting the amps gain knob (ie trim pot, ie volume knob...not master volume knob) to a point where it needs more input voltage (ie 8 volts) to put out rated power. The lowest gain setting (ie most counter clockwise position) requires the largest input voltage to put out rated power, as indicated by the label. And vice versa.


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## TrickyRicky (Apr 5, 2009)

I agree with t3sn4f2, atleast thats the way I see it. I dont like to think that the gain is a VOLUME......for me its more of a attenuator that goes for my radio too, lol.

I know we were just using examples but in reality HU can claim up to 8v output signal, but it will usually be half of that and only reaching the peak (8v) in milli-seconds if not nano seconds, lol.


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## 14642 (May 19, 2008)

I love this one. If you say the amp must work harder, then we can speak in Joules, which is a defined measure of work. A Joule is the energy expended in applying one Newton of force through one meter or in passing one amp of current through a resistance of one ohm for one second. For electricity, we can simplify that to one watt for one second. So, if our amplifier puts out 100 watts for one second, it does 100 Joules of work. 

Doesn't matter what the input voltage is, so long as it puts out 100 watts. 

Simple.


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