Stereo connections to 12v system
My boat came with a 4-channel stereo/cd player that wasn't hooked up, and no manual either. The PO had wired everything to one speaker and that was good enough for him. I've been trying to get it set up right, but I'm running into some strange problems.
My speakers are very basic 6" paper cones, and there are only two of them mounted on the cabin bulkhead. The wires run to where the batteries are kept under the main cabin settee, and are marked with a black stripe to signify the ground for the speaker.
The wires from the tuner are a hot red and ground black, and green and grey wires that (I presume) carry the front and back channels. This is the setup I'm using: the ground wires from the speakers are spliced together and connected to the battery negative terminal, and the positive leads form the speakers are connected to the leads from one color of wire from the tuner -- in this case, the green wire.
However, I'm getting some very strange behavior from the system. When I connect the two ground leads from the speakers to each other, I get sound from the speakers. Yet neither speaker is connected to ground, only to each other, and both are mounted to a teak bulkhead. When I connect them to the negative battery terminal I get much better sound quality -- but here's the weird part: if I turn the radio off and back on again, the speakers don't work. However, if I disconnect the main negative lead from the battery and reconnect it, the speakers start working again.
It's got nothing to do with the radio: its light comes right on every time. It's just the speakers that refuse their duty unless I disconnect them from the negative lead and reconnect them.
If anybody has an explanation for that behavior, I'd love to hear it.