wiring a 4 channel amp.

[impaled 10+ year member]

i already have my new sub amp in, so now its on to the 4 channel. for some reason it just dawned on me that i do not only have the 4 door speakers to wire to the amp, but i also have 4 tweeters as well. the 4 tweeters (and the rest of the system) were installed at a shop by the previous owner of my car.

the amp is pushing 4 x 111 at 4 ohms. the speakers are 4 ohms and the tweeters are also at 4 ohms.

for some reason i cannot think correctly... i could run one speaker and one tweeter in parallel on each channel and be at 8 ohms... right? could the amp run safely at 8 ohms? if that would cut the wattage in half, it would actually be ideal because i am over amping the speakers at 111 by a little bit.

if you have any ideas that will work, please do not hesitate to post.

please do not flame me, im just trying to learn.

thank you for your time and for any advice that you may give me.

Click to read more...

 

[kross 10+ year member]

There should be a passive crossover for those speakers. The crossover splits the signal coming from your amp for the midrange speaker and the tweeter. If they aren't in the back located by the amp, then they might be mounted inside the door.

So the previous owner upgraded the speakers, and kept the amp when he sold you the car? Or the speakers are, and always have been, running off of HU power?

And never just wire the midrange and tweeter in parallel!

 

[impaled 10+ year member]

all of the speakers and tweeters were ran off of the head unit, and now i am deciding to amp them.

if i shouldnt run them in parallel, what should i do???

 

[kross 10+ year member]

There are a couple reasons why you wouldn't wire them in parallel. The main one, is you'd be sending high-power, low frequency signal to the tweeters, which would destroy them. Sending high frequencies to the midrange won't damage it, but it would sound better if they were filtered out. This is what a crossover does. It sends the lows to the midrange speaker, and the highs to the tweeter.

The second is, by wiring them in parallel, you'd end up with a 2-ohm load, which may or may not be what you want.

You say you have 4 sets of component speakers. Are the rears mounted in the rear deck? Can you inspect the wiring from the trunk? If so, hopefully you'll find crossovers for those speakers mounted close to the speakers. It's a box with a single pair of wires coming from the HU, and 2 pairs of wires coming out, one to the midrange, and one to the tweeter. If you can find it, then great, you'd just wire your amp to that, for the rears anyway. For the fronts, common mounting locations for the crossovers might be inside the door panel, or under the dash somewhere.

I hope this helps!

-- Kevin