I did cut mine last weekend, just replaced the plug with a 4pin xlr. I'm extremely happy with the results. I did exactly the same few weeks ago with my Denon AH-D7000 and very satisfied also. According to the tech who did the mod for me, the HD800 have a very high quality cable from factory, copper with silver plating, so it's a waste to replace it . But, like with interconnects, to each his own. I like both headphones with the BHA-1 ( they're completely different ), and the amp drives both very well. Can't comment on the HD800 improvment, as I purchased them after the amp, and never used them with anything else. But the AH-D7000, I've had for a couple of years, and used with different amps, they're much easier to drive compared to the HD800, having 25 ohms compared to 300 ohms, and more sensitive, but regardless, they never sounded as good as with the BHA-1. My sourcs are the BCD-1 balanced , and the BDA-1 unbalanced for now. I would say with the HD800 and BDA-1 unbalanced, you have to increase the volume quite a bit, as I loose already 6 db to balanced connection as James explained it. Once I'm balanced, everything is perfectly OK, even having 300 ohms. Denons, not an issue with any input. End result, I'm in love with that amp.