Speaker pop during amp shutdown..

[b34tBoX 0]

HU = Alpine 9885

Amp1 (top) = Soundstream 2 Ch 550 Watt Amplifier TRX 2.550

Amp2 (bottom) = Soundstream 1500 Watt Monoblock Class D Amplifier TRX1500D

Speakers (front) = CDT Components 6.5

Speakers (rear) = CDT coaxial 6x9

This is weird, last year I had the same problem but I didn't have the extra battery in the trunk and grounded directly to the sheetmetal.

I figured the amp was to blame after some troubleshooting, I RMA'd it.

This year I added the battery, using the replacement amp which is the same one and the speakers STILL pop during shutdown. Top amp.

Picture of setup.

http://b34tbox.googlepages.com/IMG_2964.jpg

Here's a video of the problem. The speakers pop when the top amp's green light turns off.

http://www.youtube.com/watch?v=p5O6hsgyRC4

It looks like the top amp is not discharging properly.

What else could I check.

How does the light activity look?

[sqjeep 9]

I really couldnt hear the pop in the video. So is it the front speakers or your sub??

[b34tBoX 0]

I really couldnt hear the pop in the video. So is it the front speakers or your sub??

It happens right @ 00:20.

Only the front components, which are hooked up to the top amp pop. The rears which are connected directly to the HU do not pop, nor the sub.

Edited June 30, 2009 by b34tBoX

[sqjeep 9]

The old school Soundstream amp were known for this problem. Now I dont know if they ever fixed the problem or not. The only way i know how to fix it is by wiring a toogle switch which would allow u to turn off the amps b4 you even turn off the vehicle. Even over at DIY they put a delay inline with the headunit so the amps power down before the headunit.

This switch would do the trick Parts Express. Just take your remote wire going to that amp and put this inline with it.

Hope this helps

Edited June 30, 2009 by sqjeep

[Mark LaFountain 1,054]

what is your ground grounded to exactly? Try something solid, like a seat bolt (after you strip it), or some sort of solid frame (after you strip it)

[b34tBoX 0]

The sad part is, I all ready have an inline switch for the remote wire, and it STILL pops when I shut the amps off before the headunit.

Possibly HU ground issue?

I would have assumed that if it were the case, then the rear speakers would pop as well..

[sqjeep 9]

I don't think its the headunit ground but it wouldn't hurt to try it to see if it stops. Also like SSaudio said how and where do u have ur amps grounded??

[b34tBoX 0]

I don't think its the headunit ground but it wouldn't hurt to try it to see if it stops. Also like SSaudio said how and where do u have ur amps grounded??

I posted a picture in the original post.

They are grounded at the same location.

BTW, there's also a video too. =D

Edited June 30, 2009 by b34tBoX

[b34tBoX 0]

what is your ground grounded to exactly? Try something solid, like a seat bolt (after you strip it), or some sort of solid frame (after you strip it)

Just for kicks I changed the -BATT lead from the trunk to the seatbelt bolt.The amps behaved the exact same. =[

[b34tBoX 0]

Right now I have one remote turn-on lead going from the HU to the 1500 to the 550.

As in, the wire goes into 1500, and then another wire goes from that terminal to the terminal on the 500. (daisy chained)

I think last year, I went from the 550 first then the 1500, and my sub popped instead.

Am I running the remote lead improperly?

Maybe there's too much voltage through the remote lead? Maybe put a resistor inline?

Was thinking about doing this: http://www.mobileaudio.com/rac-faq/rac-faq_2.html#SEC14

But figured if I turn the amps off with the switch and they still pop, it may not actually help.

Edited July 3, 2009 by b34tBoX

[b34tBoX 0]

I'm going to measure the voltage of the remote lead during amp turn-on and amp turn-off and see if I notice anything suspicious..

[jcarter1885 995]

I'm going to measure the voltage of the remote lead during amp turn-on and amp turn-off and see if I notice anything suspicious..

Ive had this problem before, check your remote wires' connection at the radio to the amps, and the wire between that for damage. If thats not the problem then split the remote wires before daisy chaining them, maybe the amps dont like to be wired like that. As you can tell when you switched them from last year the sound switched from what speakers it came from, and if it is not the remote turn on wire itself then its the amps; some amps just have a loud delay turn off from some reason.

[b34tBoX 0]

Well the remote read 11.5V at the amp terminals, and no spikes during startup or shutdown.

Actually the noise is coming from 80% the left side. I switched RCA's Left to Right the noise remained the same. Then I swapped the speaker wire for left and right, and the noise moved mostly to the right.

Someone suggested I install a resistor to the remote lead?

[jcarter1885 995]

Well the remote read 11.5V at the amp terminals, and no spikes during startup or shutdown.

Actually the noise is coming from 80% the left side. I switched RCA's Left to Right the noise remained the same. Then I swapped the speaker wire for left and right, and the noise moved mostly to the right.

Someone suggested I install a resistor to the remote lead?

It sounds like whatever side the noise is coming from it may be something wrong with that speaker wire, check to make sure its not pinched or a bad speaker wire from the amp to whatever speaker its hooked up to.