[MikeW]

I recently acquired a balanced headphone amp, I want to re-terminate my Denon D2000 to balanced, I already recabled them a few years ago, I can't remember with exactly what, but im pretty sure it's Mogami 2534.
 
I can easily take apart the TRS connector and figure out what is L+ and R+ but of course then two - connections are together on the sleeve. How do I determine L- and R- without dismantling the headphones and doing a continuity check.
 
Does L- and R- actually have to be on the correct pins?  does it matter if they are switched?
 
Reterminating with Neutrik NC4MXX

 

[PleasantSounds]

It does matter that they are not mixed up.
I used ohm meter to identify the pairs.