weird speaker setup, how to connect?

turbochris · 07-08-2004, 02:57 PM

I'm getting rid of the head unit in my car and replacing it with the carputer and an amp. The car has some nice speakers in it already, but what's weird is there's 4 speakers in the front, two 5 inch 4 ohm and two 3 inch 4 ohm tweeters with a crossover built into them. These are connected in parallel for the left and right channels, wouldn't this appear as a 2 ohm speaker to the amp? The rear 6x9 speakers are 8 ohm. What kind of amp should i use and how should I hook it up?

I just installed an old soundblaster AWE64 Gold soundcard in the carputer, I tested it with some good PC speakers and it sounds really sweet!

brandon · 07-08-2004, 03:00 PM

the tweeters and mids both run into a crossover before making it to the amp, correct?

turbochris · 07-08-2004, 03:18 PM

The tweeters have the crossover built into them, it's a coil and a capacitor, the mids go right to the amp. Pretty weird, huh?

brandon · 07-08-2004, 03:43 PM

Uncommon to me, but I'm sure others have seen it before. I feel automotive manufacturers should keep out of the audio industry and let others take care of it for themselves. or at least contract some real experts to design the systems... anyhow.
It's very common to run more than one speaker or set of speakers on each channel of an amp.
In parallel wiring, which if the speakers are identical, would halve the impedance, dividing the channel's power between the speakers.
If you have two 4 ohm speakers and wire both directly to the single channel of an amp, the amp will see a 2 ohm load, and divide it's 2 ohm rated power between the two speakers, giving each speaker the amp's full 4 ohm rated power. (or close to it. keep in mind there are other factors like efficiency and loss to heat)
I'd assume you could run the tweet and the mid to the same channel, but hopefully someone who has encountered this will chime in.
Time for me to go to work.

Jailer · 07-12-2004, 09:25 PM

As long as the tweeters are crossed over you should be able to run the 5" and tweeters on the same channel provided your amp is 2 ohm stable. Most amps are 2 ohm stable so this shouldn't be a problem unless it's a very low end amp. If it is 2 ohm stable, wire the 5" and tweeters in parallel and you'll present a 2 ohm load on the amplifier. Is this a factory setup or are they aftermarket speakers? As far as what type of amp to use I'd say check out either Orion (their HCCA amps are excellent, a lot of bang for the buck) or Phoenix gold if you've got the cash for them. I'm sure everyone else would be more than willing their personal favorite also.