TheExaminer

I bought this 92 Formula last winter, and with all the work I've done I'm just now getting around to the sound system. The radio is a decent Kenwood (KDC-BT645U), but the system the PO had is partially removed. The radio works, but no sound comes out of the speakers because I don't think they are connected to this radio. I have the wiring harness pictured below in my rear hatch. I'm guessing the four copper wires are speaker wires, and the blue wires are already at the back of the radio. The larger copper wire looks like the one that is connected to the battery, and that runs through the firewall. The black and red I'm not sure about (the little blue one is ground?) Is this amp power? If so, then what is the copper wire from the battery for? I don't know much about car audio, but it looks like the hardest part is done. Do I just plug and play here? If so, what plugs into what? I'd like to get a modest system in there, 250 watts is fine. But if the box is in the hatch, will it project toward the front enough to make a decent sound? Any help would be appreciated!

TheExaminer

Here's the under hood wire. Looks like it needs a fuse?

Stauf

iTrader: (2)

Yeah fuse is missing. Blue wire maybe a remote "on" for amp. When Ign is in on position, it supplies power to amp. Really cant tell from just the pics.

Joe Tag

iTrader: (4)

Red is constant hot to amp, blue is signal to turn amp on, black is ground, RCA jacks are input to amp from head unit. You're gonna have to figure where the speaker wires go.

Disclaimer: This is the best guess I can give without being there. But colors seem to fit this. red and black, obvious, blue is typical power antenna signal also used for amp, RCAs, obvious. Red wire goes to the underhood inline fuse.

TheExaminer

Ok, kind of makes sense, I'll have to think it through and look at it more. Is there any common amp that would be easy to plug into this setup that you could recommend that would support a good box with 4 speakers at 250ish watts? Maybe two woofers and two tweeters? Or one woofer a mid and a couple tweets--however it works--I know little about audio. I'd rather have the tweeters in the front dash, but I don't know how to connect them if the box and wiring is in the back.

devestator_x

iTrader: (1)

Ok, best I can tell, this was a 6 channel setup with a single 6 channel amp. The RCA cable with the 4 ends would be your mid range speakers front and rear, while the other one with 2 would be the subwoofer. It's up to you if you want to go that route or just get a 4 channel amp.

I can tell you that 250watts to a pair of subwoofers in the trunk will be more than loud enough if you only want a modest system, HOWEVER, you wont find a 5 channel or 6 channel amp that only puts out 250watts.

I think something like this would work for you...
http://www.sonicelectronix.com/item_...-OA1100.5.html
Match that up to a sub box that can handle 350watts @ 4 ohms or 500 watts @ 2 ohms and you will be golden. It will be MORE than enough to hear from the rear of the car.

I have a 250watt amp running 2 12" subs and I can shake the car with it. The reason is the shape of the rear hatch. It creates a folded horn effect. A small space that opens to a larger space and amplifies the sound created in the smaller space. Similar to a megaphone.

devestator_x

iTrader: (1)

Oh and as far as connecting it, Im assuming the 4 "copper" wires you have are already connected to the speakers in the factory locations, front and rear. Use a multimeter and set it to ohms and connect one wire to the red lead, then touch the black to each of the other wires until you find a combo that gives you a value other than 0. That means those 2 wires go to a single speaker. You can have a friend connect a 9v battery to each wire and listen for a small "pop" sound. All it does is push the speaker out or in once. This will help you try to find which wire goes to which speaker. Keep popping the speaker until you figure out where it is. The sub box wiring is obviously missing, but a few lengths of speaker wire and your good there.

TheExaminer

Ok, so you're saying you think the bundle of four wires need to be connected to the new amp, and then the speakers will work. The sail speakers looked ok, but the dash speakers are bad. The drivers side is totally roached, and the pass side had a silly 2" tweeter in it that I assume the PO put in. I don't know if either one of them work. I'll do those tests you suggested when I get home tonight. Thx. I have a lot to learn, but this is a start. I'm sure I'll have more questions. I might also be able to adapt a headphone to the RCA wires. Even a pre-amp signal usually shows up in that test--I've done it before with home audio equpt, but I've never messed with car audio. In fact, I have a 250 watt amp I use for my home theater system that I might be able to connect the speakers to just to see if they work. I have a small, crappy guitar amp that I might be able to use too. Til now I never thought of the two as compatible even for a test, but I guess the principles are all the same.

TheExaminer

We're not worthy, we're not worthy! Devastator, you nailed it my friend. Six outputs at the radio, 4 speakers and 2 SW's. I connected them all back up and did my headphone test at the RCA wires, and it worked! All 6 of them! Turned on the radio and I got sound in my headphones, so I know the RCA wires are connected and work. You are also right about the 4 copper wires, they are wired into the car speakers. I did the ohm test, and got a reading when I touched each wire to itself, meaning each each separate double wire, etc. So now I know they are connected to speakers. Now all I need is an amp and a box, and to replace those two front speakers! I think I know what to do, but may need to come back here if I have a question. You've been a huge help, just needed a few tips to point me in the right direction.