Actually, the bluetooth module probably has left signal, left ground, right signal and right ground. Positive and negative terminals are only seen on equipment handling balanced signals, which anything with bluetooth doesn't do.
The standard way is the following:
- left signal -> tip
- right signal -> ring
- left ground -> sleeve
- right ground -> sleeve
Or just cut the cinch connectors off of a standard $3 stereo cinch to 3,5mm jack cable. Shielding = ground, Center core = signal.
EDIT: The above is wrong.
It seems I was wrong, and the output is actually balanced. Your module seems very similar to this one:
And in there it says the following:
AUDIO_OUT_P_RIGHT and AUDIO_OUT_N_RIGHT
Right channel audio output. The au dio output lines should be routed differentially to either
the speakers or to the output amplifier, depe nding on whether or not a single-ended signal
is required. Use low impedance ground plane dedicated for the audio signals.
AUDIO_OUT_P_LEFT and AUDIO_OUT_N_LEFT
Left channel audio output. The same guidelines apply to this section as discussed
You could try to put both negative pins and check if that also shuts down the module (probably, given your earlier result). If not, that could be your way to do this. Alternatively, you could ignore the negative terminals, and just connect the positive ones and the ground of the board but this is a bit of a hack:
- left positive -> tip
- right positive -> ring
- ground -> sleeve
Note that this will leave you with half the signal amplitude, and possibly a degraded signal.
To do it properly, you need a circuit that converts between balanced and unbalanced, also called a balun, or, in electronic terms, a differential to single ended circuit.
You can do this with transformers (http://www.jensen-transformers.com/faqs.html#faq4), there are IC's to do this, or circuits with an op-amp that require a bit more electronics knowledge, like this one: http://www.ecircuitcenter.com/Circuits/adcin_diff_se/adcin_diff_se1.htm or the stuff that's discussed here: http://www.electro-tech-online.com/general-electronics-chat/92142-differential-single-ended-output-2.html
More about the transformer way of doing this (note that they describe mono signals):