Thud Coming from Subs

[ephebus]

Hello,

New to the forum and have already learned a great deal on problem solving what I have going on. Basically every time I adjust the volume from the lowest to the next level up I get a thud (drum like) through only my subs. I also get the same thud when I switch from CD to radio, and the radio stations as well as a few of the sub settings.

These are the things I have checked.
1. HU ground (not using the factory ground)
2. All the speaker connections to the HU
3. The power supply, REM cable, and Ground to the AMP
4. Readjusted all my settings on the amp it's self
5. The static shield on the HU (was = 0)
6. Tried new RCA cable and REM cable

It never did this until yesterday, when I installed my subs after camping, so I am not sure what else to check. The only other thought I had was that maybe there was a chance something blew on my AMP, but I am not sure how to check it. Any help will be much appreciated.

Pioneer 3800 HU
Jensen 400W AMP
10" Subs

Evan

[Lsharptec1]

Evan,

You say this did not happen until you installed your subs after camping.

Please explain that event in greater detail.

I suspect that something is different now, compared to before.

Did you change subwoofer enclosure size, or box type?

Larry

[ephebus]

Evan,

You say this did not happen until you installed your subs after camping.

Please explain that event in greater detail.

I suspect that something is different now, compared to before.

Did you change subwoofer enclosure size, or box type?

Larry

Sorry, Poor choice of wording. I reinstalled my setup into my truck and by reinstall, I mean I have my Amp mounted on top of my sub enclosure with my 2 subs sealed into place. The only Wires I removed from the Amp when I removed the unit was the 12+, REM, Ground, and 2 RCA plugs.

I did a little more problem solving today with a friend and I found that it was only the right Sub that was making the "thud." After eliminating all of the left component stuff from the equation I plugged the left RCA plug into the right RCA Female end (this was all done on the Amp side of the wire. When I switched that over, the right Sub worked perfect with no "Thud." This leads me to believe that there is a defect in the right RCA output on the HU. Tried a new RCA cable to eliminate the possibility that the hidden one in use was the problem. So know knowing that the right RCA output is the problem where should I go from hear? Do I have any options as fixing the problem? Can I split the Left RCA signal? Or is it to the point I should just purchase a new HU. Thanks for your help.
Evan

[I Am An Idiot]

Chances are you connected your power wire and your RCA cables before you connected the ground wire to your amp. What this did was opened a fuse on the shield of the rca inside your radio. To verify that this is your problem take a short length of small wire, strip both ends, ground one end and touch the other end to the outer part of your rca cable, the shiny part of it that you can see when it is plugged in. This should make the noise go away. Let us know what happens.

[Lsharptec1]

Evan,

You can always split the Left RCA at the amp input using a "Y" adapter.

Sadly, trying to repair a problem like this may be more costly and time consuming than replacing the HU.

I Am Not An Idiot may be correct in his remarks, but my experiences in dealing with Chinese HU manufacturers leads me to suspect that there are no fuses on the shield side of the RCA's inside the HU.

Good luck.

Larry

[audiobahnkid592]

I've always had pioneer HU's and a few newb mistakes blew a few of the outputs on them very sensative...i think you blew the chip out of the unit its a small chip probally a IMH3A.