NEED HELP! Speaker problems.....

The Mach 460 System works weirdly... if you want to replace anything you bet get ready to buy converters. a lot. or buy a new receiver/rear speakers and subs... good luck

i am in no way audio inclined to be considered knowledgeble, but this much i think i know

A neat trick we'ld use in the stereo world to connect a small amp to all the speakers w/o running new wires would be to loop the fronts and the rears together at the harness behind the stereo, run the front outputs from the amp to the rear "input" wires going to the speakers, and the rear speakers directly off the amp.
When I changed the stereo in the 98, I began to do that. Didn't have any wire color codes for any of the speakers (i.e.brown/red is Leftfront+), and thought I could wing it by using a speaker tester from the amp side of the harness, and listen to which speaker made noise.
Right front. Cool, I was in business. Got up there, and for some reason, the driver's side was also making noise.
I ended up re-wiring the entire system, which is what I should have started to do in the beginning.

To "amplify" the Mach460 wiring delema, I did a simple amp w/sub in a friends '00. Thought I'ld use the amp turn on from the stock head unit, and all would be golden. NOT! With the aftermarket amp turn on connected, the factory amps wouldn't turn on. Thought that was wierd, and disconnected the wire. Amps turned back on. Got out the multimeter to check polarity, and the amps turned off when probed . Ended up using a secondary switch to turn the sub amp on.

Just ranting...

don't know about the speaker unless there is something that senses an impedance mismatch.
reguarding cannections from stock wiring, keep in mind there is another computer that has a lot to do with all interior lights , theft system, radio, amps and more, it is called a GEM. That may be what causes some problems with aftermarket equipment. ( on 99+ )

With the Mach system, there are three amps total. One powers the front and rear tweeters, one controls the frond mids and one controls the back mids. Unless you shorted something when you connected wired it up, I can't think of any reason right now why it won't work. I wouldn't recommend just changing out the speakers unless you run them off an afterkarket HU or amp. The front mids are low-passed and putting aftermarket speakers in there wouldn't really make much of a difference.

I'll try to think of a reason why it won't work. I'm pretty sure the rear 2 amps share a fuse, along with the front amp, so I don't think it would be that. The only other thing I can think of is that the Alpine's are 4ohm and if the stocker's are 8ohm, the amp might not be capable of that low of a load.

Yeah, I think it's probably the amp. When you connected the speaker and turned it on for the first time, it was probably too much of a load on the amp and it blew it, that's why it won't work now. I don't remember if it was the left or right amp that powers the fronts. If you still have the stock speaker connected, try switching the connections on the amps in the back and see if it works.

Exactly what happened to me. I tried replacing the stock door speakers on my '00 GT with the Mach 460 and the amp gave out... sucks, but from what I understand the factory system is just flat not compatible with aftermarket speakers. I ended up replacing the amps with some nice small 2 channel Kenwoods (to get them to fit in the stock placement on my vert), re-wiring the system and wiring a sub through the sub-out on my Pioneer head unit. Sounds great now, but what would have been a couple hour job (at most) turned into a weekend project and more $$ than I wanted to spend.

By the way, before the amp went out it took the tweeters on the Infinity door speakers I bought with it....

GT2000JAY said:

Exactly what happened to me. what would have been a couple hour job (at most) turned into a weekend project

Click to expand...

I agree with everybody else its the factory amp cutting them out. It doesn't have enough power to push the aftermarket speakers and usually cuts out after a hint of bass, well thats what happened with mine anyway. I had to wire the speakers directly into the deck and bypass the Mach soundsystem.

i think it is the left rear amp. I will check for sure. wheather an amp has low or high power it should drive a speaker. It may be a fuse or an impedance mismatch. If interested I will look it up.