There are several of us out here who have been very happy with the GS-X driving the HD800. I have heard the HD800 with various "tuby" goodness, and found that I liked control and clarity without coldness that the GS-X delivered. Yes, there were a number of tube amps I liked with the HD800, my favorite was the EC Balancing Act, but over all I liked the sound (or is that lack of sound) of the GS-X, and certainly appreciate the simplicity of operation. I found the GS-X/HD800 in the same SQ league as KGSSHV/Stax SR-007s and second only to my favorite pair which is the BH/SR-009. Given relative costs, and that I can use the HD800 portably with the likes of the Pico Power and HiFi-M8, it was a strait-forward decision for me to lock in on the GS-X and HD800 and use the rest of my money for *gasp* things besides headphones.
Edited by verber - 9/5/13 at 11:00pm