I've heard these at several meets and at member's homes. I was just not quite in tune with them as I felt they were a little lean. I've had them at home on my tube amp/NOS dac and I got to say I finally hear what many of you have. These are the best dynamic piston driver headphones I've yet heard. I am sorry Lord Sennheiser for doubting your capability. They are running neck and neck with my HE-6 on speaker amps. They both have their own strengths so take your pic.
Duke, Bubu, I have seen the error of my ways.
Do you think this is a result of the Single Power? Maybe you need to come get the Balanced M^3 as well to compare.
Shahrose can comment on tube vs. SS with the HD800s