UKH

Okay, this is completely random even by the standards of UKC but...I've got some sound cancelling headphones where the internal wire going through them has broken. It's a 9 core cable and because of the diameter of the wires it would be a right pain to fix the break but I think I could probably rewire it if I had a suitable (extremely thin) 9 core cable.

Anyone got anything like that hanging about? I only need 30cm of it or something, probably less. They weren't expensive headphones but I just hate chucking things out if they are repairable!

How thin, and can you use 2 cables instead of one? I guess you mean the cable linking the two cans?

Mobile phone headphones with push to talk and a mic' built in have a lot of cores (7 IIRC) in the 1mm ish cable but separating and soldering is a monumental pain in the ass I wouldn't want to repeat!

You can get ribbon cables on that shopping site. You might be able to recycle an old IDE disk drive cable. Just cut it down to the right number of cores.

It's thin, maybe 2mm in diameter! I guess I could do it with 2 cables, I'd have to drill some holes to make another run for the other cable but it's not a bad idea (and yes, it's the linking cable)

I'm not looking forward to soldering this one, my soldering skills aren't amazing!

Hmmm, I think even cut down IDE cable might be too bulky. I might see how bulky the cores of patch cable are although I'm ready to be disappointed, the cores in this cable are so thin!

I believe any kind of basic thin speaker cable would do the job if it's just linking the two cans back together? Noise cancellation comes from a phase inverted mic feeding outside noise back into the cans, so I'd presume independent of what's connecting them?

I've no clue as to what all the wires are for. Some go off to a battery, there's also a volume control on one of the cans. I suspect some go from one can to the other, through some electronics and back to the first can again but who knows, I'm keen to just replace the wiring as is.

Hmm the modern ones do get complicated 🙁 could you describe how the fault is affecting the headphones? 

- no audio passing?

- Left channel working but no Right signal etc?

No sound in either can (I've snipped the cable, the sound had stopped in both by the time I snipped it!)

2mm, that is fiddly!

Does it need to be that thin or would a fatter cable or bundle fit? Farnell do a 5.5mm OD 10way screened cable by the meter. Part no. 1619703

If it's not currently screened you could get the slightly thinner 8way version and use the screen as an extra core. Not really sure where you'd get much thinner than this off a reel (as opposed to by the whole reel)

RS do one at 3.9mm OD but you'd be looking at ~£55 for a whole reel.

I'd Hack up a cheap set of PTT mic+earbud phone headphones, use 2 runs. You'll need a good lens, scalpel and tweezers to find the cores but they're colour lacquered so when you find them you know which is which.

jk

If it is internal wiring and not subject to any strain, then I would look at using 9 strands of kynar-insulated wire (30AWG or 0.25mm). Super-duper thin and you can get 9 strands within a 2mm circle no probs. You might find it sold as suitable for wire-wrapping.