[bik2101]

can someone tell me which is ground and which is signal on the hd800 connectors?

 

[Iniamyen]

It's not critical, since "signal" goes both positive and negative. If you want to make sure they are both in phase you could probably assume symmetry between the sides, (i.e., both of the "bottom" contacts are "signal.")
 
If you have to be absolutely sure, why not just use a multimeter between the 1/4" plug and the contacts at the headphone?

 

[qusp]

the negative pole has a slightly raised bar on the outside of the barrel, which is also mirrored on the inside, the assembly inside the barrel has a 2 part metal sleeve that surrounds the solder terminals that has a slot cut in it and this will only slide into the outside barrel when it is aligned to the side with the slightly raised bar on the outside. so the negative side has 2 visual indicators that look like a negative symbol. sorry i don't have any pics handy to illustrate, hopefully thats clear.

 

[Toxic Cables]

Quote:

the negative pole has a slightly raised bar on the outside of the barrel, which is also mirrored on the inside, the assembly inside the barrel has a 2 part metal sleeve that surrounds the solder terminals that has a slot cut in it and this will only slide into the outside barrel when it is aligned to the side with the slightly raised bar on the outside. so the negative side has 2 visual indicators that look like a negative symbol. sorry i don't have any pics handy to illustrate, hopefully thats clear.

Sorry to bring up an old thread, i believe the info given above is incorrect (or i just read it wrong).
 
As indicated in the picture below, #1 with the raised bar should be + signal while #2 should  be - return.
 
 

 

[etc6849]

I agree with Toxic. Here's what I get and the equipment I used.