Speaker buzzzzzz!

[zplan]

My Mach 460 sound system occasionally has a high pitched buzz sound in speakers. It goes up in pitch with engine RPMs , then quits beyond ~2000 RPM. Also hear a "pop" sound in the speakers when I step on the brake pedal. Neither problem happens all of the time, but both always occur together. The volume control has no effect on the loudness of these sounds. Dealership says the amp is bad, but can be easily repaired for a small fortune. Doe anyone know the cure? Where can I get schematics/wiring diagrams for the amp(s)?

[tireburner163]

it sounds like you have some interference from your alternator.

[bwscowboy]

I have the same problem in my 94GT. I don't know how to properly fix this problem, but when I have the amp on the driver side unplugged, I don't have the problem. Even with it unplugged the sound is good enough for me (I don't notice any difference actually). Sometime down the road I guess I'll put in a better system. If anyone has had this problem and fixed it, what did you do?


Jim

[scout928]

My 94GT (Mach-460) has recently started to experience a similar buzz from the driver-side rear speaker and was told the amplifier needs to be replaced. The noise occurs with the factory or alternate headunit. One thing about it, the buzz is not consistant and occurs depending on outside temperature or if I hit a deep pothole -- what is the possibility of a loose wire connection on the rear speaker/amplifier?

Does anybody offer refurbished OEM Mach 460 amplifiers? My 94GT car is still in stock condition w/95K miles, no leaks and want to keep it in original condition prior to selling it down the road.

Thanks - Scout

[Meotchh]

Hmm sounds like it could be a bad amplifier, a loose ground or a speaker wire shorting to ground? Those are the three areas I would concern myself with. Not knowing much about the reliability of the Mach460 system I would first check the grounds before opting for a new amp.
It is not "interference" from the altenator. Rather it is the induced noise of the charging system. This could also be caused by loose component(s) inside the amplifier.

[scout928]

I had a after market stereo installed, Eclipse, with the Soundgate module and dual connectors for quick-connection to factory wire harness. I'll either pull the head unit out to check for chaving and verify all wires are connected securely via electrical tape (prefer solder). This gives me the ability to quickly connect the factory Mach460 Stereo to see if the same noise occurs, if so it's what you mentioned previously.


Thanks - this gives me something to checkout!

scout