Car Audio Help

[GilpinGuy]

I bought this truck (from a forum member) with a pretty bad ass sound system. I usually have podcasts going but when I crank the tunes, it's awesome. The best sounding system I've ever owned.

There are some sub woofers under the rear seat. I've had this deep sound coming from them over the last few days at random, even when there's nothing playing and the volume is down to zero. It's a real deep "whump", sometimes a few in rapid succession. Also, when I turn the ignition off, I get one final "whump" every time.

It's not very loud, but it's noticeable. When I first heard it when idling I thought it was my exhaust kind of puffing out of the tailpipe in a weird way and I actually got out and went to the tailpipe to listen.

I'm not real good with this audio stuff. Any ideas on where to start trouble shooting?

[SouthPaw]

Check grounds?

[ChickNorris]

Can't say myself. Bill @ premier car audio in denver is a +1. I miss his mobile business. He'd probably just help over the phone since you're so far out.

[Grant H.]

Agreed.

Check the grounds on the amps.

Also, check to see if there are power caps for the amps. If present, check that the connections are tight. If they are going bad, it's harder to diagnose, but it is possible. Get a multi meter and watch the voltage across them while turning the truck off (from being on). If the voltage spikes, then it is likely the cap is failing.

[Honey Badger282.8]

Pops are usually caused by an improper delay between the headunit powering up/down and the amp powering up/down. Since yours is popping at random, you either have a bad ground or something in the amplifier is shorting out. Check your connections first, then lightly shake the amplifier and listen for something rattling. If you’re not worried about a warranty you could open the amp and look for any bad caps or signs of a short.

[BPTactical]

Careful with the caps, they can bite you.

[GilpinGuy]

Ok, I'll look into connections and such when I have a chance. I don't even know where the amplifier(s) are. LOL Under the seat is my guess.

[Graves]

What kind of truck is it and what components are in it right now? Factory head unit?

Might be a ground issue but unlikely. Lots of variables here, is the amp tied in through a line out converter? Also could be an issue with the amp too. Is there a direct remote wire ran to it, or is it set up to power up when it senses audio? Take a pic of the amp's control panel (usually on one of the sides with the knobs and switches).

My money is on a factory sound system with an aftermarket amp/sub combo wired in with a line out converter because if it does it when you listen to podcasts which usually have no bass, most line outs are set up to power the amp up once it senses any type of good quick bass regardless if the stereo is on or not. It's a feature that deals with most factory head units not having a remote wire output.


ETA: also post a pic of the wiring to the amp.

[KS63]

Tried contacting the member you bought it from and ask if he’d know what might be the culprit?

[GilpinGuy]

What kind of truck is it and what components are in it right now? Factory head unit?

Might be a ground issue but unlikely. Lots of variables here, is the amp tied in through a line out converter? Also could be an issue with the amp too. Is there a direct remote wire ran to it, or is it set up to power up when it senses audio? Take a pic of the amp's control panel (usually on one of the sides with the knobs and switches).

My money is on a factory sound system with an aftermarket amp/sub combo wired in with a line out converter because if it does it when you listen to podcasts which usually have no bass, most line outs are set up to power the amp up once it senses any type of good quick bass regardless if the stereo is on or not. It's a feature that deals with most factory head units not having a remote wire output.


ETA: also post a pic of the wiring to the amp.

Aftermarket head unit. 2001 F-150. I can't answer the rest of your questions yet. If I can't figure this out I'll post pics, etc. Thanks!

[SideShow Bob]

Careful with the caps, they can bite you.

And accidentally short the wrong thing out & they will go KABOOM......

[GilpinGuy]

I don't even know what "caps" are or look like, but I don't plan on disassembling any amps or anything. Basic looking and stuff and making sure all connections are tight is about as far I'll go for now.

[Honey Badger282.8]

I don't even know what "caps" are or look like, but I don't plan on disassembling any amps or anything. Basic looking and stuff and making sure all connections are tight is about as far I'll go for now.

They look like a tube with power wires connected to it.
76470

The ones iside side the amplifier look like short AA batteries and are soldered to the board.
https://d2gg9evh47fn9z.cloudfront.net/800px_COLOURBOX1700060.jpg

[colorider]

The noise you are hearing can be caused by a cell phone. Get in the vehicle with no phone with you or nearby and see it it still happens.

[Irving]

The noise you are hearing can be caused by a cell phone. Get in the vehicle with no phone with you or nearby and see it it still happens.

I've heard that happen on desk top sound systems before, right before you receive a call. I haven't heard that in a long time though.

[GilpinGuy]

I've been connecting my phone to the system via bluetooth for a few years and never had this happen before, but I'll give that a try anyway.

Thanks for all the tips guys.

[Irving]

Some of my devices do what you're describing when they are plugged in, but not playing anything.

[00tec]

Have you replaced/messed around with the battery lately? In my experience, startup/shutdown pop can be caused by a loose ground.

Otherwise, these are the other options:

http://caraudioadvice.com/how-to-fix-amp-speaker-turn-on-turn-off-pop/