I got rid of the one a s only set of headphones I ever liked (mostly because I was never exposed to anything better...) - Sennheiser HD 280 Pro because, even after one year of being stretched over a bunch of books, it still hurty head after a few hours of wearing them... I was reading Sennheiser HD 660 S reviews and the only real Con that reviews mentioned was the clamping... Has anyone been able to compare HD 660 S to 280 Pro's? Was the clamping uat as bad? My audio card is ASUA Xonar DGX and I like it because it's the only damn card with such excellent low-latency UNi Xonar drivers... Creative drivers such in comparison, BUT they are more recent and updated with better support for Windows 10, so I am not sure... Does anyone remember the impedence formula? I think it was something like 10 ohms for the audio card ana 150 for the headphones... Finally, is there a relatively cheap DAC or amplifier or whatever else that would go well with UNi Xonar DGX and Sennheiser HD 660 S? Once again, I could live without that if it's not worth it and justnspend $500 on HS 660 S? Are there even better headphones for $500 - $600? I want something that would let me hear tll HQ wave and flac files like they should be heard - with HQ hardware!