Mach 460 Audio Nightmare!!!!

[Saleen613]

Hi all,
New to the site and looking for you audio experts out there, especially when dealing with this MACH 460 stuff. Now before anyone says to take it out, or MACH 460 sucks, please understand, that I'm not trying to go crazy on car speakers/amp/subs. Not my style. My friend has the MACH 460 and it sounds pretty damn good, IMO, for a factory setup. Long story short, the car started out as a 98 V6, it now has a 99 GT motor in it, along with all the wiring converted for 99+. The donor car also had MACH 460 stuff. I moved it over to mine and hooked everything up just as it was in the other. Problem is, I turn the car on, and the only sound thats coming out, is from the tweeters, but only if i turn the factory radio all the way up, and you can barely even hear that. No sound coming from the 5x7 in the doors, or the rear deck. I have read that the front amp/radio controls the 4 tweeters/midrange and that the front amp also sends a signal to the rear amps to turn on. I did check the rear amps by swapping with a buddy of mine that also has a 98 GT with MACH 460 and the rear amps are fine. Put them back in mine, still no dice. WTF??? I checked the two audio fuses and they're fine. I did notice a fuse that was blown that controls the cigarette lighter but, that wouldn't cause the speakers not to turn on, right? Any help on that matter would be a huge help.
Thanks in advance!

 

[Saleen613]

UPDATE:
Problem solved. I was using the factory headunit that came with MY mustang when I bought it back in 1998. I did not use the donor as I assumed since they looked the same and harnesses plugged right in, it wouldn't be an issue. Installed an aftermarket deck and voila! All 8 speakers came on.

 

[Saleen613]

UPDATE:
I linked two videos of my install for a better visual of my ordeal. Enjoy!!!

 

[kalvick]

an aftermarket radio usually sounds murky with a mach 460. i think the amplifier on the head unit goes to the amplifiers on the mach and the sound quaility goes done. Can you try to donor radio and test it out?

 

[Saleen613]

Kalvick
I'm not sure I follow your question.

 

[kalvick]

the stock reciever sends a signal to the amps on the mach 460 and you get ok sound. when you use a aftermarket radio with a built in amp, you are sending the amped signal to another amp in the mach 460. then the sound gets murky. I suggested that you use the donor car reciever and plug it in. if the fidelity sounds much clearer than your aftermarket radio then you know there is a still a problem with your setup and you need to use a non amplified aftermarket reciever.

 

[Saleen613]

That may be, but the problem I had was a.) My stock receiver was not a MACH 460 and b.) it may have been fried as I was only getting signal to the tweeters. I then plugged in an aftermarket HU and all the speakers came alive.

 

[kalvick]

When I first got my mustang, the first thing I did was rip out the stock receiver (cuz i wanted to play MP3's) I never even turned the stock radio on and I plugged in my aftermarket stereo. the sound was always meh, but I chalked it up to being crap paper speakers. my wife gets into my car one day (she hates being in my car) and I had the stereo on and she said it sounded like ass. Then from that day on I noticed every distortion and low fidelity sound. I took it to an audio shop and they told me, my aftermarket reciever had a built in amp and I was sending an amped signal to the mach 460 and all the audio was being phased out and distorted. thats when I ripped out the mach 460 and got an aftermarket amp / speakers and the sound quality was night and day difference.

I know you want to keep the mach 460, thats why I am suggesting you make sure the after market reciever is not being pumped thru any internal amps.

 

[Saleen613]

I get what you're saying, but again I had NO SOUND whatsoever. So by replacing with an aftermarket HU, and for all 8 speakers to come on, was a relief in itself. I have replacement speakers for all, and so far so good. Thanks for the info.

 

[IcedTea]

Just a word of advice if you plan on putting aftermarket speakers with the mach amps. 4ohm after market speakers will burn your 460 amps up eventually . The stock mach 460 speakers are 6 ohm speakers wired in parallel for a final impedance of 3ohms. So if you just plug and play some 4ohm after market speakers they will have a final impedance of 2ohm when the amps are designed for a 3ohm load.

 

[40oz]

When I first got my mustang, the first thing I did was rip out the stock receiver (cuz i wanted to play MP3's) I never even turned the stock radio on and I plugged in my aftermarket stereo. the sound was always meh, but I chalked it up to being crap paper speakers. my wife gets into my car one day (she hates being in my car) and I had the stereo on and she said it sounded like ass. Then from that day on I noticed every distortion and low fidelity sound. I took it to an audio shop and they told me, my aftermarket reciever had a built in amp and I was sending an amped signal to the mach 460 and all the audio was being phased out and distorted. thats when I ripped out the mach 460 and got an aftermarket amp / speakers and the sound quality was night and day difference.

I know you want to keep the mach 460, thats why I am suggesting you make sure the after market reciever is not being pumped thru any internal amps.

If you are replacing the stock head unit, you might as well replace the whole system, as you found out. The Mach 460 system is pretty good as stereos go, especially for a stock system. But if you are intent on an aftermarket system, yes, you need to replace the system, not just swap in a headunit and think that's good.