The Bose CD/Cassette head unit can be utilized without the Bose signal conditioner. Bose subwoofer amps and speakers by using the head unit four pre-amp outputs to drive external aftermarket power amplifiers and speaker. Use the Shielded wires or chassis for signal return. DO NOT USE signals Common on C4(13), LT BLU or Common C4(7) YEL. These are the only interface to the Bose signal processor.

The head unit RADIO ON output can be used to switch on external power amplifiers. Be safe and use an inline .5 amp fuse to protect the head unit.

Wiring Info
The following are the Bose head unit 4 channel pre-amp outputs
Signal CD/Radio Color Code
LF out C4(9) TAN/BLK
RF out C4(10) LT GRN/BLK
LR out C4(11) BRN
RR out C4(12) DK BLU
Common C4(13) LT BLU – DO NOT USE FOR EXTERNAL POWER AMP
Shield C4(14) Bare Wire
Ground C4(15) BLK

The following are the Bose head unit 4 channel power amp inputs
LF C3(1) DRK GRN
RF C3(2) LT GRN
LR C3(3) BRN/WHT
RR C3(4) BLK
Common C3(7) YEL – DO NOT USE FOR EXTERNAL POWER AMP
Shield C3(8) Bare Wire

The following are the Bose head unit power and control signals
Signal CD/Radio connection
SW+12 out C1(18) DK GRN – Radio “ON” Signal
Power C1(10) ORG
Ground C1(5) BLK/WHT

You will need to use 4 RCA cables to connect the head unit to the amp, not speaker wire. 2 for the front left and right, and two for the rear left, and right.
I bought 10 foot cables at Radio Shack that only had one male end and the other was raw wire. Looking at the cut end of an RCS cable, the outside wire is negative and the inside is positive.

1. If you purchase RCA Cables with two male connectors, cut one end off and strip the insulation.
2. For each channel you will see a thin wire with shielding around it and there will be alot of individual strands of wire around that. Unwrap the individual wires from the shielded wire and twist them. This becomes the negative wire for that channel. You will do this for all channels.
3. Take one RCA connect one of the shielded inner wire and splice it to the LF out C4(9) TAN/BLK wire coming out of the stereo harness. Take the other shielded inner wire from the second cable and splice it into the RF out C4(10) LT GRN/BLK wire coming out of the stereo harness. Take both negative wires from the RCA Cables and splice them into the clear shielded wire coming out of the stereo harness. This completes the front left and right RCA connections.
4. Do the exact same thing with the second set of RCA cable to connect the rears using LR out C4(11) BRN and RR out C4(12) DK BLU coming from the stereo harness. Splice the negative RCA wires into the clear shielded wire coming out of the stereo harness.
5. Connect an 18 gauge wire to the SW +12 out C1(8) DK GRN, Radio “ON” signal coming out of the stereo harness and run this to the amp “Turn On”
6. Run a Power Wire from the battery t the amp
7. Run a ground wire form your amp to a seat belt bolt, or in the rear to the frame. Easily accessed by pulling the rear panel and a taillight.


Hope this helps.

I found that the RCA cable negative wiring that is wrapped around the cable to be pretty tender, you can't mangle it much, otherwise it breaks.

I ran my front RCA's to my amp, don't use rear speakers in any of my setups. They are unplugged.
The amp I am using, an Alpine, has the rear two channels bridged to run the subwoofer.

I was pleasantly surprised at how nice the system sounds with just the stock HU. I have Alpine's in my other cars with similar speakers and it hangs in there.