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83 Posts
Discussion Starter · #1 ·

I have searched till I am blue, and I still can't find an anwer to these questions. I am looking to upgrade the subs, and add a dedicated sub amp (Or simply replace the stocker), but need some answers:

1. From the schematics, it appears as if the stock amp in the trunk only drives the 6.5" subs. Correct?

2. It also appears as if the amp gets it's signal from line level output from the rear, two way speakers. Correct?

3. If so, is the signal from the rear speakers crossed over or low pass filtered before entering the amp, or does the amp have an internal crossover?

4. Finally, if the signal is crossed over/filtered before the amp, what is the frequency?



· Registered
92 Posts


GM Engineers scatch thier heads when you ask about Sub, mid & High freequencies and respond with, are you having whistling sounds come out of your engine?

Dude, first buy new speakers all the way around, but some real subwoofers 10" or 12's. Buy an amp for the subs & and amp for the four rear speakers. I recomend buying any head unit that has 3 pre-outs in the rear, preferably Eclipse. Three pre-outs, one for HIgh's, Mids & Non-Fade/Subs, Hook up your Non fade Output to the sub amp & hook up your 4 channel amp to your four mid output to the back speakers, even if you have to piggy back the amp. Your head unit will be pluged into the front speakers if your using a harness. Adjust the balance of the head unit concentrating to the face to the front speakers. Now put you stereo on a satisfactory high volume and adujst the sub amp to satisfactory position, same with the back four speakers.

four the best cleanest sound, target your front speakers to high frequency ranges and attempt to minimize the Bass volume to the front, let your amps controll the bass volume and boost. Focus your four rear speakers to a High- to Mid range frequency thru the in-amp cross over. And channel the sub woofer to sub frequencies only.

Always adjust stereo system with "loud" feature off, for best modification.

If you don't live to far from me I can help you out just supply lunch! I know how to install car stereo systems, provided you have all the goodies!

I work for Fujitsu who also owns Fujitsu-Ten who Makes Eclipse Mobile Audio components. Yes I get a killer cost discount and no i cant get you any speakers or head units. they are strict on employee purchases.

anyway's take care and good luck.


· Registered
108 Posts
Goatmann, good tips, but I don't want to go all out... I am looking to do the same thing, just wanting to replace the stock sub setup. Not looking to add stuff to the trunk, etc. I just want to find an upgrade for the two rear stock sub locations (Don't care about a bigger size, not looking to compete here) and add an aftermarket amp. Anyone ever done this before?

Thanks for your input,

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