Mach 1000 Head Unit Replacement Help!

Discussion in 'Mustang Sound & Shine All' started by sseeba, Sep 17, 2012.

  1. So my Mach 1000 head unit in my 2003 vert has hit the fan. After months of temperamental ejecting/loading CDs, it has finally hopelessly jammed one. I am experienced with HU replacement and I intend to replace it with an aftermarket head unit but have some questions about how to wire it to properly integrate the factory amps/subs. I’ve been trying to read these forums and elsewhere but it has left me with questions…

    I know I need this harness - The Metra 70-5519. It appears the HU will power tweeters with the RCAs sending a signal to the amps for the car woofers and trunk subwoofers. But why is there only one set? Does one go to the woofer amps and the other to the subwoofer amps? This would make a weird setup that could be solved with RCA Y-adapters (although still mono). Or do they daisy chain in stereo to all amps? Do I need to set a low pass filter or do the woofer/subwoofer amps have a built-in crossover?

    I also know I need a high pass filter solution for the tweeters, this seems to have been done from the factory HU. What frequency should I set the high pass crossover to?

    Any recommendation on what RCA output voltage I should look for on the new HU? I would think higher is better, like 4v? I don’t know what the factory unit provided to the amps.

    Finally, do the factory amps require a different voltage than the 12v amp turn-on lead provided by aftermarket head units. I was reading it worked for some but others had to add resistors to drop voltage to something like 5v to prevent turn-on noise/popping. Would this product work for that - The Metra AFDI-5V.

    I love my Stang and the sound of the Mach 1000 but man is it unnecessarily complicated.

    Any help would be appreciated. Since a comprehensive Mach 1000 tutorial seems unavailable online, I will take detailed pictures of the wiring/install and detail exactly what I did so others can do this a little easier than me.

  2. I was a professional installer for years, and if memory serves me correct that system will work better with a 5v amp turn on signal. Yes, that should be the correct harness and yes that 5v adapter will work. When I didn't have those, I made my own voltage dividing network to drop the HU '12v' remote wire in half and also a resistor to provide a 'slower' turn-on, thus eliminating any audible turn on 'pop'. I never had a vehicle come back doing it this way either. Also, there are only 2 RCA connections beacuse the amps get a mono signal, 1 RCA per amp. Somehow I managed to always hook them up and have correct sound position (subconcious memory, like firing order/plug orientations?). Don't quote me on everything, I haven't done one in years. I know this post is a couple months old, but if you still need help I can surely dig something up from my past.

    I may have my Ford systems mixed up, I've seen so may since the 80's standard and premium packages. You either Y the Rights and also Y the Lefts or the way i mentioned above. It's a simple trial/error with the RCAs either way. Depending on the new HU, you would either set a HPF for the internal amp (regular harness' wiring) or use inline caps on the wiring if the HU isn't that fancy.