Same old question... with a twist.

[scotty3x3]

Ok. So I know how to check the amp gain levels with the multimeter and test tone. What I don't understand is why we should set the gains with a flat eq. What confuses me is this... I set my amp gain with my eq completely flat. I don't listen to music with my eq completely flat... I add low bass, cut some mid bass around 500hz and then add some highs. If I set my gain at max without clipping with a flat eq, won't I start clipping when I push more bass from the headunit's eq? Also... what if I have a crossover that has a variable frequency bass boost like the 6 channel clarion. Say I want to boost down around 27-30hz for the really low bass... won't this then push my amp into the clipping range?

Or am I missing the fundamentals of how amps work?

Thanks!

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[garychurch84 10+ year member]

Set your HU they way you want it then set gains on the amp.with that being said any boost can promote clipping

 

[bradl79 10+ year member]

I don't know why either, maybe BC of possible distortion. I always set mine with EQ on

 

[Da64u 10+ year member]

Ok. So I know how to check the amp gain levels with the multimeter and test tone. What I don't understand is why we should set the gains with a flat eq. What confuses me is this... I set my amp gain with my eq completely flat. I don't listen to music with my eq completely flat... I add low bass, cut some mid bass around 500hz and then add some highs. If I set my gain at max without clipping with a flat eq, won't I start clipping when I push more bass from the headunit's eq? Also... what if I have a crossover that has a variable frequency bass boost like the 6 channel clarion. Say I want to boost down around 27-30hz for the really low bass... won't this then push my amp into the clipping range?
Or am I kissing the fundamentals of how amps work?

Thanks!

The moment you boost anything you bring distortion into the equation.

 

[bbeljefe]

You can accomplish the same sound preference goal by attenuating all but the frequencies you like while leaving them flat and doing so before you gain set will ensure that you aren't clipping. However, setting with a multimeter can not ensure that you're not clipping... regardless of where you have the EQ set before gain adjustments.

Using a multimeter to set gain is like using a hammer to install a screw.

 

[hispls 5,000+ posts]

The moment you boost anything you bring distortion into the equation.

Including turning up the volume? Calling BS on this. There's plenty of equipment that can boost without any significant distortion.

Ok. So I know how to check the amp gain levels with the multimeter and test tone. What I don't understand is why we should set the gains with a flat eq. What confuses me is this... I set my amp gain with my eq completely flat. I don't listen to music with my eq completely flat... I add low bass, cut some mid bass around 500hz and then add some highs. If I set my gain at max without clipping with a flat eq, won't I start clipping when I push more bass from the headunit's eq? Also... what if I have a crossover that has a variable frequency bass boost like the 6 channel clarion. Say I want to boost down around 27-30hz for the really low bass... won't this then push my amp into the clipping range?
Or am I kissing the fundamentals of how amps work?

Thanks!

The point is your amp sees a different load at every frequency so the whole idea of setting gains at one frequency with a DMM is absurd and your magical SMD black-box is even more absurd.

If you want to play music set the gains using your ears. If you're chasing numbers, set the gains using the termlab.

 

[scotty3x3]

Including turning up the volume? Calling BS on this. There's plenty of equipment that can boost without any significant distortion.


The point is your amp sees a different load at every frequency so the whole idea of setting gains at one frequency with a DMM is absurd and your magical SMD black-box is even more absurd.

If you want to play music set the gains using your ears. If you're chasing numbers, set the gains using the termlab.

The goal is simply to not damage my equipment. I installed a Kicker CompR loaded enclosure with two 12" subs (800 RMS Each) and a Pioneer 9601 (800 RMS) mono amp. This is nowhere near extravagant as some of you guys' equipment but I still don't want to destroy it. I don't change EQ settings very often, but I do turn the system WAY up when driving with the windows and sunroof open on the interstate. I don't want to turn the system up for a 30 minute drive and end up damaging any of the components. I figure if I set gains to 2 or 3 volts LOWER than where they start clipping, I shouldn't have to worry about that. Is this train of thought on the wrong track?

 

[OzNath 10+ year member]

That's a question i always wondered about. This is how i set my gains. Say on my hu my max sub volume is 6 i set my gains with it 1 below max and with a flat eq on, i don't use multi metres to do it, i just uplug my 4 channel rca and play a 50 hz tone or some really bassie song that slams the lows and just turn the gain up untill distortion and back it off a tad and then go in my hu setting and put the sub control to 3 or 2 and adjust my eq the way i want. I know i won't clip because i set the gains with the sub control up and now i have it down a fairbit to make adjustments with the eq =)

 

[scotty3x3]

Ok so I created the test tone and put it on a thumb drive. I left the EQ as it was and turned the volume up to 3/4. This particular amp, instead of having gain 0-12 or the like, it has readings... "6.5v" is lowest then "H" which the manual says is for 4 volt RCA outputs (this is only about 1/4 of a turn from all the way down), then "normal" which is for 2 volts etc. I have 4 volt RCA so I should be setting it at "H". We'll, wouldn't you know it, the volt reading is right where it is supposed to be when I get to the "H". So, the manual is correct when it says going over the "H" will introduce distortion. That's great.

The problem is that there is virtually no sub sound whatsoever when I set it there. I have 100 watt rms to my kappa door speakers from an alpine amp. To get the sound to balance at all, I have to turn the speaker level down to -11 and the sub level up to max, which is +10. Even when I do this, the subs are still WAAAAAY under performing.

When I reconnect the bass knob that came with the amp and have it to max, the voltage jumps by 20 over what the max says it should be. Even then, I feel that the subs are not producing what they should. I know 800 rms split to two 800 rms subs is only 400 each... but still, there's no way that 400 total watts for door speakers should be more than 4 times as loud as 800 total watts coming from subs. I shouldn't have to lower the db of each door speaker by 11 and boost the subs by 10 to get balance. Any ideas what could be wrong???

 

[hispls 5,000+ posts]

Ok so I created the test tone and put it on a thumb drive. I left the EQ as it was and turned the volume up to 3/4. This particular amp, instead of having gain 0-12 or the like, it has readings... "6.5v" is lowest then "H" which the manual says is for 4 volt RCA outputs (this is only about 1/4 of a turn from all the way down), then "normal" which is for 2 volts etc. I have 4 volt RCA so I should be setting it at "H". We'll, wouldn't you know it, the volt reading is right where it is supposed to be when I get to the "H". So, the manual is correct when it says going over the "H" will introduce distortion. That's great.
The problem is that there is virtually no sub sound whatsoever when I set it there. I have 100 watt rms to my kappa door speakers from an alpine amp. To get the sound to balance at all, I have to turn the speaker level down to -11 and the sub level up to max, which is +10. Even when I do this, the subs are still WAAAAAY under performing.

When I reconnect the bass knob that came with the amp and have it to max, the voltage jumps by 20 over what the max says it should be. Even then, I feel that the subs are not producing what they should. I know 800 rms split to two 800 rms subs is only 400 each... but still, there's no way that 400 total watts for door speakers should be more than 4 times as loud as 800 total watts coming from subs. I shouldn't have to lower the db of each door speaker by 11 and boost the subs by 10 to get balance. Any ideas what could be wrong???

500w would sound roughly twice as loud as 100w assuming equal efficiency between the two systems and no losses or compression.

Use your ears and some common sense.

 

[scotty3x3]

500w would sound roughly twice as loud as 100w assuming equal efficiency between the two systems and no losses or compression.
Use your ears and some common sense.

What? Where do you get 500 from? The door speakers put out 100 each for a total of 400 and the amp should be putting out 400 to each sub for a total of 800. So with that being said, the subs should be twice as loud as the door speakers. Yet, I have to turn the door speakers down and the subs up for them to balance. To me, that's exactly opposite of what I SHOULD have to do.

I don't see how I'm not using common sense. Especially when the manual says to set it at "H" for 4 volt preamp outputs. I'm trying to not damage my equipment and wondering if you guys think something might be wrong with my amp.

 

[hispls 5,000+ posts]

What? Where do you get 500 from? The door speakers put out 100 each for a total of 400 and the amp should be putting out 400 to each sub for a total of 800. So with that being said, the subs should be twice as loud as the door speakers. Yet, I have to turn the door speakers down and the subs up for them to balance. To me, that's exactly opposite of what I SHOULD have to do.
I don't see how I'm not using common sense. Especially when the manual says to set it at "H" for 4 volt preamp outputs. I'm trying to not damage my equipment and wondering if you guys think something might be wrong with my amp.

Sorry. 800W will be a little less than "twice as loud" as 100W.

Set the gains so that things sound good and you have enough flexibility to have adequate volume even on songs with low recording levels. When you use your volume knob and hear things distort, hear the woofer bottom out, or smell something burning turn things down.

The point being that if you like to listen to anything else besides a 0db 50hz test tone setting gains based on that is absurd on its face.

 

[T3mpest 10+ year member]

Sorry. 800W will be a little less than "twice as loud" as 100W.
Set the gains so that things sound good and you have enough flexibility to have adequate volume even on songs with low recording levels. When you use your volume knob and hear things distort, hear the woofer bottom out, or smell something burning turn things down.

The point being that if you like to listen to anything else besides a 0db 50hz test tone setting gains based on that is absurd on its face.

Agreed on all points, I've ranted on this so many times I've given up, but it's good to see people coming around lol.