using a multimeter to get a perfect gain structure

[ilikesound]

does anyone know what my multimeter should read if i were driving a pair of momo 6.5's and momo 6x9's from a c400.4 amplifier? what is the ideal gain setting for each channel and what should it read? also, if i were to drive a momo 8'' sub from an alpine mrp-m450 monoblock, what should that read? help would be greatly appreciated!:D

[Thom]

You need the Autosound 2000 CD #104. Play the -6 db tracks and use an o- scope to see when the signal starts to clip.

[ilikesound]

hav you seen the tutorial on the JL website about setting gains? that is why i ask, they have a chart that you can cross-reference for their amps which is why i ask

[Josh]

There are too many variables to consider. Like the HU output voltage (3/4 volume doesn't seem very acurate), the battery supply voltage for the amp (from the battery), crossover settings, etc. It's a good start, but not the best method out there. I don't think we have any such settings. I'll forward this to Kim.

[Kim]

All of our MOMO amplifiers allow you to select from two different input Voltage settings.
If the output Voltage of your head unit is 2 Volts or less, then set the input Voltage to low. If the output Voltage is 4 to 8 Volts, then use the "High" setting.

I like to set the gain by turning up the volume on the head unit to the 3/4 position and adjust the gain control on the amplifier until you hear just the slightest amount of distortion, then back it down slightly until it's gone.
This will save both the amplifier and your speakers. Some folks don't like to do this because it doesn't get loud fast enough. But they don't see the advantage. This will reduce the noise floor. You won't hear your tweeters hissing. Unfortunately not too many people are going to have a CD that is recorded at "0 dB" at 50 and 1000 Hertz to set their gain levels.
If you have it, great, then use it. If not, trust your ears.

[PoweredByDodge]

I've been generating 60 Hz tones, throwing them onto a cd, and then playing them. Lets you measure with a 5 dollar hunk of junk meter... but its not going to give you any idea of where clipping is... I only use it AFTER I've set my gains, as a way to make sure that I'm getting the same power to the left and right speakers.

I'll set the left, set the right, and then check them volt with the test tone / meter, and use the lower value of the two as my setting.

It's only for 'balance' (or 'fade' if you're so inclined).

Lacking a scope, I agree wholly with Kim as to how you should set your gains. If you've got a scope, then have fun.

[MacLeod]

Kim gave the best answer on how to set gains. Ive been setting them that way for over 15 years and have yet to blow a speaker. Nothing wrong with using a multimeter but a speaker will be more than happy to tell you when its being overdriven. ;)