car audio

[bungea]

im installing a sub and amp to my aftermarket stereo. I have everything hooked up and when i change the track on my cd player i hear a thump. On lpf on the amp i can hear the music with little distortion but on full or hpf i hear a thumping sound making the sub continuously. Im running a 200 watt mtx amp with a 200 what max mtx sub.

I don't want to use a ground loop, id rather find the source and fix it.

Car is a 2007 grand prix gt if that info is needed. power wire is ran on passenger side do to battery on that side, and remote and rca on the other. ground is by the bolts on trim on rear seats where the top of the seat latches and to bring down the seats for more cargo room

[Stealthee]

LPF is short for low pass filter, HPF is short for high pass filter. What that switch is is for a crossover. When set to low pass it will only let the low frequency signals through. With the subwoofer you want it set on low pass.

It sounds to me like something is not hooked up properly or something is not making proper connection. I have the exact same amp and it works flawlessly.

[Moppie]

Originally Posted by bungea

im installing a sub and amp to my aftermarket stereo. I have everything hooked up and when i change the track on my cd player i hear a thump.

Had an old head unit that used to do this through the speakers.
Was something in the head unit that put out a signal during changes in track.
Sounds like the amp is picking it up and amplifying it through the sub.

[bungea]

yes i do have an old aftermarket stereo, but buying a new head unit a jvc kd s27 i believe does the same thing. i'll have to check all my wiring again, hopefully not down pouring like it is today, but im sure all connections are tight.

[bungea]

does the ground wire placement matter where i have it or would it be better by the seat belts? Also when i take the rca's out the noise stops, i put one in and other out and noise isn't there either, place the other in and the noise begins. I'm almost thinking its the rca's.

[Moppie]

Originally Posted by bungea

does the ground wire placement matter where i have it or would it be better by the seat belts? Also when i take the rca's out the noise stops, i put one in and other out and noise isn't there either, place the other in and the noise begins. I'm almost thinking its the rca's.

Could be a bad connection inside the RCA?


The earth contact just needs to be metal to metal, and directly to the frame of the car to be sure that is a good connection.

[bungea]

the connection I'm using right now is metal to metal. I don't know if your familiar with the 04 to 08 grand Prix;s but the rear seats fold down and there's a plastic trim but behind is a metal washer then my ground wire, then the metal of the chassis.


regarding the RCA's, i just bought a new pack of RCA's and will be trying that out tomorrow along with checking for tightness on the other wires from the deck.

[bungea]

to let you guys know the issue was the rca cables. thanks for the posts.

[Moppie]

Originally Posted by bungea

to let you guys know the issue was the rca cables. thanks for the posts.

Awesome!

Glad you got it fixed, how does it sound now?

[bungea]

alot better then what it did in my 97 grand prix. Only thing is that the bass rattles the right rear speaker a little. trying to figure how how i can re-mount them so it don't happen.