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jmw703
09-19-2011, 08:21 PM
Ok so I have an alpine cde 100 and it only has 1 2v output which was to for a 900 rms amp.. So I had to get a PAC RCA signal booster which helped a ton but now I don't know where my gain should be set because idk what my RCA voltage is.

Any ideas ?

slvrado28z
09-19-2011, 08:26 PM
what sub and amp are you running

ace_800
09-19-2011, 08:33 PM
Either set it by ear or the real way with an O-scope. Sub and amp model don't matter.

dragnix
09-19-2011, 08:43 PM
Either set it by ear or the real way with an O-scope. Sub and amp model don't matter.

real expensive way

jmw703
09-19-2011, 09:58 PM
OK so i found out that i had a multimeter to measure the voltage. Just to clarify i want to make sure i set this right.

Heres what i did. I have a 900 rms x 1 channel @ 2 ohm amp.. but i only want 800 rms @2 ohm so 800x2ohm = 1600 , sqrt of 1600 is 40 so i want to turn the gain up until it reaches just under 40.

all bass boosters and eqs were set to 0.

I put in a 50 hz tone into the cd player and turned to 28/40 volume, sub bass knob set to max,

put the corresponding meter terminals to touch the speaker wire terminals on the amp and i raised the gain until it reached just under 40v on the meter.

Is this correct?

BnGRacing
09-20-2011, 05:06 AM
OK so i found out that i had a multimeter to measure the voltage. Just to clarify i want to make sure i set this right.

Heres what i did. I have a 900 rms x 1 channel @ 2 ohm amp.. but i only want 800 rms @2 ohm so 800x2ohm = 1600 , sqrt of 1600 is 40 so i want to turn the gain up until it reaches just under 40.

all bass boosters and eqs were set to 0.

I put in a 50 hz tone into the cd player and turned to 28/40 volume, sub bass knob set to max,

put the corresponding meter terminals to touch the speaker wire terminals on the amp and i raised the gain until it reached just under 40v on the meter.

Is this correct?


It's a correct use of Ohm's Law, however you can still be clipping. The only way to really tell if you set the gain correctly is if you used an o-scope. There's also no reason to set your gains lower on the amp b/c you have a thing called a volume knob. The amp's gain has absolutely nothing to do with what subwoofer is hooked up to it. If you're worried about overpowering, keep the sub volume on your HU down a click or two.

subzero
09-20-2011, 07:01 AM
Ok so I have an alpine cde 100 and it only has 1 2v output which was to for a 900 rms amp.. So I had to get a PAC RCA signal booster which helped a ton but now I don't know where my gain should be set because idk what my RCA voltage is.

Any ideas ?

test the RCA voltage with a dmm set in ac settings. if it is a true 2vout, then you should see 2v. playing test tone of 60hz. Once you confirmed that you have 2v, you should step it down a notch till you read like 1.8v. That should prevent clipping. Now you can hook up the rcas to the sub amp and begin setting the gain. turn up the gain till you notice the distortion. It wont get any louder, but it will get more clipped. Thats where an oscope comes in. which is why I siad 1.8v That should be sufficient to keep it from clipping. too much