Everytime I powerup the stereo in my truck, I get a loud pop or thunk from my subwoofers. After that they work fine. I just replaced my old Alpine with a new Alpine headunit and they still do the same thing. What could be causing this because it doesnt sound good? Thanks!

 

Deck turn on thump. Can usually be remedied by delaying the amp turn on. Amps also have a turn on thump but most designs are fairly quiet or not noticable...and some are loud.

 

Yup, exactley what he said.

They make turn on delays but I cant remember where I saw them.
Or just put a switch on the REM line and wait till everything is powered up, then hit the switch to turn on the amp.

 

Does it thump when you turn the system off too?

 

If your Alpine has a REM wire, be sure that is the one you are using for the amp turn-on lead. Some folks use the power antenna lead and it doesn't have the delay that the REM wire has...

 

It only thumps when I turn it on. I have the Remote wire tapped into one of the 12volt key on wires on the factory harness. Maybe I should take it off and attach it to the harness on the headunit?

 

STwater - I just recently had a similar experience in my 2000 F150 Extended cab. I am using an Alpine CDA-9831 head unit that made this terrible "POP!" or "THUMP" when I turned the system on or off. I searched around other forums and learned I should check several things but in a nutshell the remedy was simple. My installer hooked the 12V remote wire from my amp incorrectly to the "Ignition Wire" (which is red) on the back of my head unit. This allowed the amp to be fully powerd up and running a few seconds before the head unit booted up (2 to 4 seconds). This also permited my amp to stay powerd on even if I turned the head unit off. Tech support at Alpine said that this is a sure sign that the 12V remote wire to the amp is connected incorrectly.

Last night I pulled the head unit, clipped the amp's remote wire from the red wire and reattached it to the white/blue "remote" lead on my head unit. All is better now. No thump at all. Check yours and make sure your amp's turn on lead is connected to the head unit's "Remote" wire which should be white and blue just like mine.

I hope this helps.

Mike

 

LOL! THATS EXACTLY WHAT HAPPENED TO ME! It was hooked up to the 12volt red wire. I removed it and hooked it up to my blue remote wire and all is well now Thanks guys! Now heres one more situation.... My rear door speakers are much quieter than my fronts for some strange reason. They are new speakers and a new headunit. I tried swapping them with the fronts and they still do the same thing. Any ideas???

 

Good to here you fixed your problem. Dang installers :>/

Do you have your fader set correctly?

 

It sounded a little low in the back so I faded to the rear speakers and you can barely hear the music, but if you fade forward its loud and crystal clear. I can't figure it out. I dont fade it at all when im listening normally but I know it should be a lot louder than it is.

 

If you are powering your door speakers with a four channel amp then try the following: switch the speakers wires on the 4-channel amp so that the front door speakers are being powered by the rear channel on the sub and wire the rear door speakers so that they are powered by the front channel of the sub. (Basically - wire it just opposite as you have it now). Give your system a test and see if the speakers in the front show the symptoms you are having now in the rears. If so then there is something amuck with your amp.

I'm not sure how your amp operates but make sure that the gain setting on the front speakers equal the gain settings on the back. If the gains are set correctly then you may have a bad rear channel output on that amp. Also, check your connections and wiring. You may have a wire that has damaged insulation causing some shorting to ground or your connections at the speaker terminals may be defective.

Let me know how it goes.

Mike

 

This may also be of interest to you. I just got pictures of my new system. Check it out.



http://home.comcast.net/~mrmsudawgs/Truckaudio.html]My System

 

Thats a nice site. The thing is im not powering the door speakers off an amp. They are just being powered off the headunit. The only thing hooked up to my amp is the 2 10s under my back seat. It really weird. Any other ideas? Thanks!

 

It sounds like you have a head unit problem. Fortunately for you its located on the rear speakers and not the fronts where your soundstage imaging is so important. I have mine faded to F7 on my fronts so I can barely hear my rears anyway. Unless it is just one of those annoying things that stays in your mind I would just leave it alone and count your blessings that it is not the fronts with the problem. Otherwise, I'd contact Alpine's tech support line and ask them to troubleshoot it for you over the phone.

Good luck!

Mike

 

Thats the thing though. It did it with my old Alpine and my new Alpine. I know the speakers are good and I have a different wiring harness in there now, Im confused. I think I may have to re run the wire to the rear speakers with some 16 gauge wire.