[elwappo99]

I've searched high and low for an answer, with no luck. Any help? 
I know they are basic, but I really appreciate the help.
 
1. If you use a multimeter (digital) what ohms setting should be used?
 
2. Could you cut a headphone cable (with 4 wires inside) and then probe those cables to see which makes a circuit to determine which is a ground for the left and right channels, or can that damage the drivers? 
 
thank you so much in advance

 

[Juaquin]

1) Any ohm range that would be applicable to the resistance you are measuring. You can't hurt anything by going over or under - if you go under it will just show 1. (meaning that the resistance is over what can currently be measured), if you go over you'll just lose precision and can step down the range to the correct one. Headphones are generally 32-600 ohms (some are more, a few may be less).
 
2) The easiest way to determine ground would be to place one probe on the ground of the jack (the "sleeve" portion of the jack, farthest from the tip), and then probe the other wires for continuity (your meter should have a continuity setting where it buzzes - if not, just set to the lowest resistance range and look for near-0 resistance). A multimeter should not damage headphone drivers AFAIK.
 
Most headphones have only a single ground channel (shared between left and right), unless they are high-end "balanced" headphones. What pair do you have?
 
Nice to see someone else from UCLA on the board!

 

[elwappo99]

Thank you so much for your help!
 
that's what I figured for the checking of a headphone by the TRS connector, but I didn't want to blow a driver.  I was thinking of other applications for this, like testing a newly installed headphone cable to check if any issues came up.
 
I was going to reterminate my pair of Grado sr225's, which from what I read, has 4 wires in it. I'm later on making cables for my hd650, and I was going to use a stock cable to probe as a guide for cable making.
 
There's actually a few head-fiers at UCLA. I'm really surprised. In my dealings I've met about 4, and heard of a few more.

 

[Juaquin]

If it uses a TRS connector (which is unbalanced), then two of those 4 wires will be ground, so there should be almost 0 resistance between them and it doesn't really matter which goes to which driver. Make sure to post pics!