Phiber Optik

iTrader: (2)

No it's a DEI EQ, and it is only hooked up to the sub amp and does have that low level rumble that you described. The 4 channel amp's signal comes directly from my pioneer head unit. I have disconnected the RCA's and the noise does go away, but I ran new RCA cables inside the car and hooked those up and it had the same noise. So I think it is being caused by the power or ground for the deck.

Can someone tell me the best power to use for the constant 12v and acessory 12v, and a good ground location for the head unit.

MIKE-P-28

iTrader: (1)

On all the 7's I did, and mine too. I always, used the cig lighters 12V constant for the 12V constant for the deck. I grounded the deck to the metal substructure below the radio.

Ok so you most definately have pre-amp noise and you are corect that it is coming from the headunit / eq combo.

So if you have noise in the sub amp and also in the high amp. Its most likely the deck.

Sometimes IT may not be how its grounded at all, it may just be a simple input/ output mismatch impedance difference between the rca of the head and the input rca of the amp...

Also you need to remember, you can have noise through the sub amp and it feed back through the high amp.

You need to reduce the system as small as possible and start troubleshooting the system in its smaller form... 1st remove the rca's on the amp, take it out of the loop. Then try to get rid of the noise through the sub amp...

If you have a pair of those RCA inline filters I suggest using them. It will probally solve your problem...

Also have you regrounded the motor to the chassis.

I use to use a piece of 8 awg from the alternator bracket to the strut tower, this used to get rid of noise in some noisey systems, try it... It will only make things better anyways.

LMK what heppens

djmickyg

that goes on the power which is DC but the amp puts out AC
hell no u dont want dc to the speaks, it will only fry the voice coil. and a cliping amp will do the same!

i hate problem solving a trubles car system... theres so many thing to check.

doesnt ur deak have a Triger 12v for the amps?

Phiber Optik

iTrader: (2)

djmickyg: yes my deck has a remote 12v wire...

MIKE-P-28: The cig lighter is only on when the car is on, or in the acc position. I am using thr cig lighter for the accessory 12v but what are you using for the constant 12? I am using the small single lead brown connection for the stock radio for constant 12v.

I ran a wire from the alternator bracket to the top of the strut tower and no improvement.

The noise disapears when the RCA's are disconnected from the amp.

MIKE-P-28

iTrader: (1)

Duh thats right its 84-85 ooops missed that 1.

There is a constant wire back there on later models to use, its single pin

MIKE-P-28

iTrader: (1)

Use a low level in line noise decoupler, the input/output signals are mismatched, this adapter combines the ground of the headunit with the ground of the amp. TRust me here

Phiber Optik

iTrader: (2)

MIKE-P-28: I called a bunch of electronics shops and none of them knew what that was. Then I called the stereo shops and 1 said they had it and it was just the same thing that I bought and connects to the RCA's and it took out some of the frequencies of the music.