ls13coco
100+ Head-Fier
I got the K7XX's last year and really dislike them for gaming because I found it difficult to tell where the sounds were coming from. The soundstage is a little bigger than some of my other headphones I've had (HD600 and the HE-400i) but what it gains in soundstage it loses in imaging. The sound gets a little muddy in the transition from the low end to the mid range. That's what I really dislike about the sound on them.
So, I don't use them for gaming or music but I do like them for movies. The HE-400i are better but I returned them due to disliking the build quality, the cord and I experienced some pain in the ear area. But the sound was good. I liked them just a little more than my HD600's.
As for others bringing up the power supply I strongly recommend upgrading. The improved sound quality is just flat out amazing - on speakers. The one I got was on amazon... www.amazon.com/gp/product/B019HW0UBU/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1
Hearing what you said, I'm glad I splurged for the 712 rather than the 7xx.
I just got them yesterday morning, burned in with pink noise for probably 6 hours.
Using them with 2x dual and 2x single Sparkos op-amps, with much experience with the HE400i and HD 598 and I can say that they seem great! Music, and gaming has been what I expected from the reviews. Used them in a competitive FPS called Day of Infamy last night and I'd clearly hear an enemy coming from the left rear and be ready before he comes around the corner.