What I soldered together is exactly as WNBC describes - an XLR (female) adapter with four banana plugs. I bought a Q-cable with XLR male, so it's a simple matter of connecting the XLRs.
Soldering was not brilliant but the main thing is to check
with a multi-meter that you have the right pins to the right plugs and good connections (should be zero resistance if you have the right pin/plug; infinite e.g. "0.L" otherwise).
Positives (red speaker terminals) get odd-numbered pins; negatives are evens. Left channel gets pins 1 and 2. A handy source to verify the right connections (and more) is Rob Robinette's site
(aka robrob on headfi I believe).
As the III already has XLR hp sockets, there should be little or no difference between these and the adapter. Might be a difference with adapter versus TRS though? There is definitely a perceived large difference with the model II.
Finally here, XLR socket artfully (ha!) arranged at front of Taboo, is pictorial evidence. Hastily snapped just now with no attention to lighting or composition, make of it what you will
The shocking pink cable received wife approval but was "forced choice". Having ordered new plugs and sockets but finding I had no speaker cable in the house, I butchered the pink speaker cable illustrated instead. Well, at least it saved me soldering the banana plugs I'd ordered...Edited by Argo Duck - 1/28/14 at 2:00pm