Looking for a little help from those with more audio/electronics talent than me.

The audio system in my car was there when I bought it 2 years ago. Here's a run down on parts: Alpine deck, Alpine DSP, Alpine CD changer, upgraded speakers (unkown make) in stock locations except in hatch (they've been disconnected), Bazooka tube in hatch, Alpine (MRV-F300) 2/3/4 channel amp (powering all speakers except sub), and a Rockford Fosgate Punch 100a2 amp (powering the sub).

The wiring (electrical and speakers) seems to be of decent quality and gauge.

The problem I'm having has existed since the day I bought the car and has very slowly been getting worse. Here's what's happening: all the speakers (except the sub) will cut out every so often. There's no real regularity to it, bumps in the road don't necessarily make them cut off and on, and I can't make it happen. It use to only cut out just every once in a while, but would generally come right back on within a second or two. Now, it's happening very often and will cut out for up to 20 mins or more. The odd thing is that when the speakers are out, they'll cut on for less than a second (literally) about every 3 seconds (you could set a clock by how often they cycle off and on... very regular). Here's some thing real weird (one of my local audio shops thought I was a nut when I told them this), when it's acting up, I can sometimes fix it by cranking up the volume (real loud) and then down to normal levels real quick. However, that isn't working as well as it use to and generally starts back up right away more often than not.

I've checked the power to the Alpine amp and it's good. I've even checked it when the speakers were acting up and the volts were a solid 12.2. So, I don't believe it's a ground issue. I've been told that I might have a speaker wire that's grounding out, but I don't know how to check for that. Should I be checking resistance (ohms)? If so, what and how do I check? I also thought it might be the RCA jacks on the amp, but wiggling them around doesn't seem to cause or fix the problem.

Hmmm... any thoughts. I really don't want to rip out all of the speaker wiring and reinstall just to find out my amp is screwed (or vice-a-versa).

TIA,
Marc

 

i would say it sounds like a speaker is grounding out.

strat at each speaker, and trace the wire all the back to the amp. Look for cracked, slashed, or crimped wires that have the actual wire exposed. If that is not it, you have have some internal grounding issues going on in the amp. SO what you could try to do is put the RF amp on a pair of speakers, and test them (after you redo the gains, etc.)

good luck

 

does it do it at low volume or high? Or it doesn't matter? If it's going off than back on after a few seconds. Does all the speakers cut off? If so, I would say it's the amp internal ground. If it's only the front speakers or so, than it's a speaker wire grounded somwhere on the front and vice-versa. Of course, this depends on the amp manufacturer too.

It's no doubt a grounding speaker wire or internal ground on the amp but from what I have read so far. I say it's the amp.

 

Thanks for the comments so far. I was hoping I could narrow down which set of wires it might be by checking resistance or something like that. It's gonna be a PITA to pull all the panels and wires with just the hope that I find a wire grounding out somewhere.

Volume doesn't matter. High, low, all the way up (ouch), all the way down,... does it just the same. Some days are worse than others, but lately it seems to do it more often and cuts out for longer periods of time.

The really wierd thing is (like I mentioned above), when it starts cutting out bad (yeah... there's varying degrees of how bad it acts), it acts as though there's no sound at all (except for the sub), but there will be a tick of sound every 3.2 seconds. Yup, I timed it. 3.2 seconds right on the nose. And it's like that whether I'm driving or sitting still (engine running or not).

Wierd...

Thanks again,
Marc

 

Since it's not affected by hitting any bumps. I doubt it is a wiring problem.

Sounds to me like a thermal problem. Either your head unit or your amplifier is getting too hot.