GS1000 just needs a very very powerful power with lots of currents through it to make it shine,
you would detect that its signature stays,
1. recessed mids are developed, and you get lots more details,
2. it's not a dark, smooth phone like senns, expects lots of separation, layers, details... as they say the devil is in the details,
3. it has a deep bass which is controlled only when you use a good amp
4. a very good 3d sound signature again only with a good amp and its soundstage is hall-like, needless of a good amp.
over all, it's good at low volume
if u blast your headphones, this phone is not for you,
it's really meant to be enjoyed with all the subtle-ly-ties in the passages of your music,
it picks up all details (ok, not all, as compared to b&w nautilus) but it's by far the can i choose over anything else,
ultrasone ed9, would come close had it been an open can.