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Warbling earpieces following repair

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throbscottle

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I repaired my daughter's earphones a few days ago, the wire had broken where it leaves the plug. These are Marshall Minor (I think) look like this except the plug is slightly different. It's a T-R-R-S plug
So I heated up the metal plug body (just a fancy exterior for a slim moulded plug) until I could pull it off, removed the plastic moulding from the connectors. I think my mistake was to remove the bits of left over wire from the plug, all the extra heating melted the plastic pretty quickly causing a short between tip and end ring. Resolved by removing the tip. Couldn't see anything causing the short, was ok when I put it back in. Cleaned up the wire, soldered on at right angles to the plug and kind of curled it round to fit in the body. 2 layers of heatshrink, fitted in the metal body with hot glue, checked ok with the multimeter, clicks heard when testing. Gave back to daughter.
When tried with Sony mobile phones, the phones said it was an unsupported type of earphone. Tried it on a tablet. Worked, but now the music sounds kind of bubbly or warbly, or underwater as Mrs described it. Even my indiscriminate hearing can tell it's wrong.
So any suggestions what could be causing this? Should I replace the plug altogether, or is there likely to be some other fault somewhere up the wire?
 

dr pepper

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Most Helpful Member
I had some weird sound effecty type thing on my personal cassette player, yes it was a while ago, the ground at the phones jack was disconnected so the phones coils were in series between left and right, there was still music but only what was out of phase, it sounded really weird, maybe something like thats happened here, newer ones use litz wire its easily damaged with heat.
 

throbscottle

Well-Known Member
That would be good explanation, but each channel gives me 30 ohms-ish to ground, and control gives 1.1k to ground (which I'm assuming is correct, it drops right down when the button's pressed).
I'm assuming I got the wiring right. The control wire has ground wrapped around it as a screen, left is red and right is some other colour, green I think, I know, opposite to normal way. So ground to sleeve, right to ring nearest tip, left to tip, control to extra ring.

All I can think of to do is take the plug off again and try a standard one. If that works I can get far more of the inserts than I need (20 inserts that look like the original) so I could use the original housing, or just get a whole plug and be eternally annoyed...
 

dr pepper

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Most Helpful Member
Yes I have seen that before, I think the manufacts do it to detect when a standard headphone is plugged in, or maybe to detect when this non standard one is plugged in.
 

throbscottle

Well-Known Member
I've now learned that the way I wired it is actually perfectly valid for certain manufacturers - probably just with older stuff though. Nokia is mentioned. I found there's a bunch of different connections for these type of plugs. I just made a mistake based on an assumption, based on what had always worked before with trs and ts plugs.
 
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