Tune gains to decrease 1700RMS to 800RMS??

[osamio]

uhh guys DMM? Set the dmm to ac volts, turn evreything down, then put gain up until it reaches 28 volts. Done.

why did it take some long for someone to finally say the right answer..

just remember to disconnect the subs when you do this

Anymore detail on how to do it? i have a dmm and stuff, and i'll disconnect the subs, hook the mm straight to the amp output? + to + and - to - ? then what?

The math behind it is easy. you have and equation for power that is: P = V²/R, p is the power your setting it too, V is the AC voltage being produced, and R is the resistance(your final ohm load)

you need to solve this equation for V so you now have: V² = P * R

So you want to do 800 rms at 1 ohm you have V²= 800 * 1, => V = sqrt(800) => V = 28.28volts

now when you do this, have you sub woofer settings on your deck set to the highest level youll ever play it at, and the volume at about 75% unless you know where it starts to clip. Disconnect the sub, wire a DMM to the pos and neg of the amp. and play at test tone. Start off with the gain on the amp at min and work you way up till the DMM reads 28.28 volts. make sure the DMM is set to AC volts

But doesn't there need to be a load on the amp? like, the subwoofer? can i just hook the dmm to the output while the subs connected, starting at low gain, then working my way up..

The multimeter act as a tiny load, That how a multimeter measures voltage from anything. Think of it like checking a batteries voltage that have just laying around.

but if you hook a sub up to it, it will be loud for testing, and youll have voltage drop which will skew the results.

Ok thank you. I was worried about shorting out the amp, but now that i think about it that's a stupid question.