Pro 900 Owner here. They are my first set of Ultrasones and actually closed cans. I absolutely love them. I listen to Hip Hop, EDM( Glitch Mob, Cutline, Skrillex, Magnetic Man, etc), and Les Claypool, Tool, Toadies. I drive them with a Audio-Gd NFb12 and a UDAC2 when on the go. I will be sticking with Ultrasone for awhile. Id really like to see if the pads from the new signature series will be my pro 900s. That would be excellent.