Help! Rear speaker install question?
 

I am replacing the rear speaker deck in my '89 911 Targa. I purchased Alpine 4x6 to replace the Eclipse speakers that were currently in the vehicle. The problem is I have 2 sets of wire for each Tweeter/Woofer hookup and the Alpines only have 2 prongs to connect.

Which do I connect the tweeter or woofer or do I solder each into one?

Here is a link on bi-wiring and bi-amping. There is a diagram that shows a bi-wiring set up. If you can identify that your wires leave the amp in the same fashion as the diagram I think you can easily figure out how to adapt to the single wire setup.

Bi-wire vs Bi-amp - AudioForums.com

Thanks but I do not have it hooked up to an amp just a newer stereo unit. The new speakers I purchased have two prongs to connect (+/-) the old speakers have four prongs (Tweeter/Woofer)

Which do I solder together?

unless there was some form of a built in crossover in the radio, which i doubt, i would think you could use either set without problem.

If I am only hooking up the Woofer, how would i push the rear tweeter?

the new speakers are wired together internally.

So you are saying to talpe off the two tweeter wires and solder the Woofers to the new speaker cable included with my new Alpines?

Based on that wiring diagram link in my first post and what "nineball" says that is what you should do.

I think you can mate the two positives to each other and two negatives to each other as well without harm but the single wire should drive the new speakers just fine. Yes tape off the set you don't use.

doesn't really matter which set of speaker wires you use so long as one is positive and one is negative.

Not too many years ago it was fairly common to have a set of speaker cross-over modules, High-Q and therefore fairly hefty modules, located between the amp and the two separate, mid-range and tweeter, speakers, or ever a mid-range and tweeter speaker assembly, but not interconnected, speakers. my '88 has the cross-over modules in the very front of the door packets, 2 wires into the cross-over network, 4 out.

Your new speakers, with only two connection terminals, will very likely have a simple bi-polar electrolytic capacitor serving as a high frequency "cross-over" network to the tweeter. If you like you can disconnect that capacitor at the tweeter voice coil end and then connect the original tweeter's "positive" power wire to the terminal you just clipped the capacitor off of.

wwest - Good info - so right now it seems there may be two sets of cross-overs - the modules and in the speakers. Suspect only one set is advisable.

If he just hooks up only one set of speaker wires as nineball and I are suggesting will this lessen performance of the new speakers? I assume there is one frequency range in one set of wires and another range in the other set.

Can the two sets of wires be merged together after the cross-over modules and re-combine the frequency ranges without effing something up - if he does not use your suggestion.

In the 87-89 Porsche parts catalog I see and part called a "Di-plexer" in the door. Part number 911-645-575-00. Our host sells the part and calls it a "crossover"

Very good info wwest

Yes, if he uses the old original speaker wires then one pair will be carrying the high frequencies and the other pair the low to mid-range.

Can they be merged together..?

No.

If I wished to go that route I would bypass the original cross-over network modules entirely.

hmmm... if it is mounted in the door it would appear to control frequencies that the door speakers would receive. the pelican diagram doesn't show any wires going into or out of it either, but that just may be an oversight.

there is a really simple solution to see what, if any, frequency control it may have over the rear speakers. connect one of the sets of lines to the new speaker and play something. if you hear no bass at all, or no high end sound, there is a crossover somewhere in the line. if you hear everything it is a full range signal.