[joe_seattle]

I got a great thrift store deal ($10) on a good pair of Sennheiser PXC-250 noise-canceling headphones. The only issue is that the headphone jack was damaged internally and one of the channels would cut out every so often and require wiggling to get going again. I figured I could easily rewire the phones...basically just slap a new radioshack plug on the end and make the connection with electrical tape and a quick solder job. I also figured I could dump the noise-canceling "wand" that I never use...so basically I planned to cut out the noise-canceling wand, shorten the overall cable length and connect a new jack to the shortened cable. What I found when opening up the noise-canceling wand is that the cable for each ear piece has within it four wires. The cord that goes from the music source/jack to the wand has the standard three wires, but once in the wand each channel gets 4 wires each. As you can see in the pic (sorry for the crappy web cam quality), each channel's cable has two copper wires and a blue and a red wire. To be clear: out of the wand there is a cable to the left ear and a cable to the right ear, and each of those cables contains four wires. Upon cutting into the cable, I found an inner plastic sheath that contained the red, blue and one of the copper wires, and the other copper wire wrapped around the plastic sheath.

What I'd like to know is, how do I wire this thing back up to a standard jack - which wire goes where? Thanks for any help you can provide!

-Joe

 

[Lil' Knight]

Are you sure each channel has 4 wires? It looks like from the pic you took, the wire is under the Y-splitter. If that's the case, then the wiring is pretty straight-forward. Red for right (Ring). Blue for left (Tip). Copper for ground (Sleeve).

 

[joe_seattle]

I just knew someone would ask...because 4 wires PER channel does seem a little crazy - but it's true. four wires per channel for a total of eight wires. See pic.

 

[joe_seattle]

No ideas on what to do? come on people...someone here is brilliant

 

[SRPP]

Not sure if this is still an relevant, but four wires per side makes perfect sense if the microphones for the noise cancelling bit are in the earpads (to minimize the timedelay from microphone to speaker).
But which wire goes where? Hmmm., well the braid is ground possibly of both the speaker and the microphone, and it should have a relatively low resistance with one of the other leads, that's the + of the speaker.