Rewire old Headphones

somuchdirt74

Estimable
Jun 12, 2014
3
0
4,520
Hope this is the right spot. My father gave me these headphones (Sony Mdr-7509) a while back so I want to fix them because I like them and for sentimental reasons.

Anyways, the left ear works perfectly but there is no sound coming out of the right ear. I've done some soldering before but I'm not sure what to solder in this case.

Right Ear:
Dh3wUBu.jpg


Left Ear:
D3aq5Ok.jpg
 
Solution
As best I can tell from the pictures here is how it is wired:

left side: the input cable from the plug has three wires - red, green, and black. The green seems to be the left signal, the red the right signal, and the black is common. there is a black wire with two conductors which i see leaving l=the left and heading toward the right, but it's not clear how it is connected on the right side.

I see a red wire going from what looks like the interconnect to the right speaker with another red wire. If the gray wire is truly hanging loose, it is likely the common for the right ear, and needs to be connected to the other conductor of the interconnect.
----
To confirm that the right-channel wire is bad in the cord to the plug, simply...
There don't seem to be any bad solder joints but it is hard to tell. You need to check that the speaker itself is not bad. You can apply a headphone level signal to the speaker itself at the point where the red and black wires are soldered.
There may also be a broken wire going into the headphones.
 

somuchdirt74

Estimable
Jun 12, 2014
3
0
4,520



I'm not sure how to apply a headphone level signal to the speaker. I tried looking that up online but I'm not really sure what you mean by it or how to do it.

The pictures are not all that great but I can submit more if I need to. The red and black wire are twisted to each other, they are not soldered to anything in the area where they are joined. The other end of the red wire is soldered. The thick grey wire is only soldered to one side while the other part of the part is just dangling, it is not soldered.
 

tomc53

Estimable
Jun 6, 2014
52
0
4,610


As best I can tell from the pictures here is how it is wired:

left side: the input cable from the plug has three wires - red, green, and black. The green seems to be the left signal, the red the right signal, and the black is common. there is a black wire with two conductors which i see leaving l=the left and heading toward the right, but it's not clear how it is connected on the right side.

I see a red wire going from what looks like the interconnect to the right speaker with another red wire. If the gray wire is truly hanging loose, it is likely the common for the right ear, and needs to be connected to the other conductor of the interconnect.
----
To confirm that the right-channel wire is bad in the cord to the plug, simply connect a jumper fro the red to green wires on the left sie. You should hear something out of the right speaker.

If that does not work, you can confrom that the right speaker is good by running a jumper from the green on the left to the red on the right, and from the black on the left to the gray on the right. if only one of these is needed to get sound, you have found the bas segment of wire, and you can check for loose connections or just replace the wire -> red to red and black to gray.
 

somuchdirt74

Estimable
Jun 12, 2014
3
0
4,520
As best I can tell from the pictures here is how it is wired:

left side: the input cable from the plug has three wires - red, green, and black. The green seems to be the left signal, the red the right signal, and the black is common. there is a black wire with two conductors which i see leaving l=the left and heading toward the right, but it's not clear how it is connected on the right side.

I see a red wire going from what looks like the interconnect to the right speaker with another red wire. If the gray wire is truly hanging loose, it is likely the common for the right ear, and needs to be connected to the other conductor of the interconnect.
----
To confirm that the right-channel wire is bad in the cord to the plug, simply connect a jumper fro the red to green wires on the left sie. You should hear something out of the right speaker.

If that does not work, you can confrom that the right speaker is good by running a jumper from the green on the left to the red on the right, and from the black on the left to the gray on the right. if only one of these is needed to get sound, you have found the bas segment of wire, and you can check for loose connections or just replace the wire -> red to red and black to gray.


I was able to get sound through the right speaker. this is what I did.
Used jumper on green and red.

UFxB48T.png


The thin black cable (interconnect?) has two wires coming out the cable.. red and copper (copper=ground?).. Both wires from the thin black cable are twisted to the red wire (one that is soldered in the circular area).. I twisted the hanging piece from the thick grey wire to the joint where the (interconnect?) and red wires connect. Then I pushed this wires down to the grey area in the picture.

gRC5Axl.png


So I can hear sound from the right speaker when I do all that. If i remove the jumper I don't hear anything so I'm still not sure what to do here.
 
Solution

tomc53

Estimable
Jun 6, 2014
52
0
4,610


It sounds like you have a bad wire from the plug to the headphones. In that case you need to replace that cable.

The easiest way to get a wire like that is to buy an extension cable and cut off the end - (RadioShack or similar - http://www.radioshack.com/product/index.jsp?productId=2103867 or http://www.radioshack.com/product/index.jsp?productId=16126226 depending on what you wnat to plug it into.

Alternate source: http://www.monoprice.com/Product?p_id=645 or http://www.monoprice.com/Product?p_id=4795