Geneva Braided 3.5mm/6.35mm Upgrade Cable for Sennheiser HD600/650/660S2/6XX/58X

Works well!

Sound precision increased a tad, actually. I wasn't' sure it a difference could be heard, but there is a slight difference in fact! Music is a little cleaner especially in high frequencies and the difference was enough to be able to push transcription verification speed up another 10 - 20%. What's nice too is there is hardly any audible noise from cable movement. To be fair, the original cable on the HD600 is longer, so the cable length may or may not be a factor too. Overall, I am pleased with it.