You've made a large statement of preference. I wish you would give us some more details as to what it is about the 500 that makes you like it so much.

I never managed to tame the treble on the HD-800 and I tried numerous valve and SS amps, and the mod as well. It had wonderful soundstaging that is for sure. The bass was good but not outstanding...
 
I think I have over-sensitive hearing and the HD-800 just did not do it for me , even with all its technical prowess...
 
The HE-500 is so much more pleasing to my ears...I love the midrange and the airiness...I seriuosly cannot find a fault with the sound...its only shortcoming is the weight.