Okay, here's the deal. I bought an 87 iroc a few weeks ago. The car was originally optioned with the Bose system, 4x6's in dash, 6x9's behind the sail panel, and 4x4?'s in the rear hatch cargo lid. However, when I got the car there was a bunch of wiring, 2 pioneer TS-A1670Rs (6.5 screwed to the cargo lid, no 6x9's, and stock 4x6's up front with a Clarion DB245 unit (whose display I really dislike). I don't care about having a loud thumping system, but I'm not particularly an audiophile either, I want something dependable that sounds good and is reasonably priced. I want all the speaker slots filled with appropriately sized speakers and I don't particularly want to have an external amp (can I drive all six without one?). Sorry for the newb questions, just want to get some decent sound going. I'd like a stock look (head unit and speaker grilles in back), but I know the cost of one of those units can be about the same as a modern head unit, no custom boxes, etc, etc. Would like to hear your speaker suggestions and what is necessary to drive all 6 speakers. Most of the manuals I've looked at describe 2 front and 2 rear speakers, than specify two subwoofer ouputs (some through an amp). So do I run the sub output to the 6x9 spot, or what should I do...? Thanks for your suggestions.

Congrats on the new car. It's always nice to know one has ended up in a new home!!!
All new car stereos on the market will only support 4 speakers due to the amount of resistance the speakers place on the unit's internal amp. If you put 6 speakers on the wires, you end up too much resistance on the amp and too much resistance=heat, i.e your stereo will get too hot and fail. The only way to get 6 speakers is to add an additional amp to run either 2 or 4 of the speakers.

The sub output on decks is called a Pre-out signal. it is a low level, un-amplified, signal around 2-4 volts thereby keeping the signal clean, (amplification=distortion) if you hook speakers directly up to these outputs, you will have no sound. (ok, maybe just a little sound, but you get my point, I hope)

My recommendation is add a small 4 channel amp and use it to run the 2 6x9 speakers in the sail panels and the 2 rear speakers, and let the stereo run the 2 front dash speakers. Typically the aftermarket amp will have a much cleaner sound due to higher quality parts (depending on brand).

I have personally installed systems in 3-4000 cars (yes, Thousands) and in the majority I have used Pioneer speakers. not just for the sound quality, which is good, but I never have to worry about them fitting, their depth fits most vehicles, including our dashes, with no modifications. your stereo head unit should be your choice, since you already brought up looks as being important, stay with the major name brands (alpine, Kenwood, JVC, Pioneer, etc, NO dual or jensens, and get one with 3 sets of RCA outputs, 1 front, 1 rear, and 1 sub out; in case you ever want to upgrade, possibly 1 or 2 8" subwoofers in the rear cover since they are already cut >Just a thought<

Lastly, Find a qualified installer in your area that you trust, ask to see photos of prior work if you are shopping for one. The quality of ANY system is in the install. usually the smaller independant shops will do a better job the the Best Buys, etc, because their reputation is their future business. Good luck with the project, PM if you need any more help. Mike

Thanks for taking the time to write out that reply! That's pretty much exactly what I needed to know.

What you said makes perfect sense to me. I don't like the clarion b/c it's got blue illumination with white lettering, almost impossible for me to read except for at night. It needs to look clean, but its got to have functionality too. I've had a Pioneer head unit before and was well pleased with it's quality. I did a little bit of looking, it seems like the Pioneer GM-6400F is suited for what I want, along with a complementary set of Pioneer speakers. I'm open to recommendations on either amp or speakers if you care to throw a couple out there. May just get a set of 6x9's and stick with what I've got available right now. I've done up my home theater system nicely and now that I've been doing some reading I don't think this will be too terribly difficult, seems pretty similar just on a different platform of sorts. I've tracked down a lot of what the p/o had done and things are much cleaner now! Thanks again.

http://www.memphiscaraudio.com/produ...ss-amplifiers/
16-MC4.75 amp

http://www.pioneerelectronics.com/PU...neer/TS-A6993R rear

http://www.pioneerelectronics.com/PU...cation/TS-P462

http://www.pioneerelectronics.com/PU...llow/TS-SW841D if you decide on a sub

Good advice, but you got the above backwards and it depends on whether the additional speakers are hooked up in series or in parallel.
Adding speakers in series increases resistance. This rise in impedance reduces an amplifier's effective output. The danger isn't heat but rather a decline in speaker output.
Adding speakers in parallel effectively does the opposite. As resistance decreases the load impedance on the amplifier also drops. With less resistance to electrical flow the amplifiers output increases. In other words to little, not to much resistance generates heat. Basically what would happen is that if the resistance drops far enough (approaching zero) what you would end-up with is a short (a fried amp). Most car audio amps are designed for 4ohms. Some will overheat and shutdown at 2ohms. Some can even go as low as 1ohm before they melt.

Headunits typically have fairly weak internal amplification and they leave little room for messing with. With external amps a person can get quite creative and design some pretty elaborate wiring set-ups. Some even combining series & parallel circuits on one design. But you need to know what your doing.

After much research today, I discovered that you were in fact correct and the person who explained all that to me was wrong. The funny part about it was that if explained his way, it also would be "correct", in theory. He stated That the lower the value in ohms, the greater the resistance. so 2 ohms is more than 4 ohms etc. I often wondered about that, it didn't seem right.