Senns HD650 vs Grado 325i

[Kaboom]

I'm using a chinese-built "Darkvoice" tube headphone amp which i am quite satisfied with. I do, however, find the sound at loud volumes to be quite harsh when paired with the grados. Not a real problem since i don't listen at high volumes (i'd like to keep my hearing in place so i can blow the walls apart when i listen through my speakers).
Nordost Solar Wind/amazing handmade solid silver litz interconnects... Cambridge Audio transport and TriVista 21 DAC.
ALL kinds of music! from Classical to Jazz to Prog to Rock, pop, Punk and even heavy metal sometimes (noticed how pop and heavy metal are the only two genres without a capital letter? teehee).
The how do i like my question is a tough one. If i'm LISTENING to it, as in critical, concentrated listening, i love detail. as much as possible. I'm the kinda guy who likes listening the the little clicks of the opening and closing of the valves on wind instruments, and i also love pinpoint imaging.
Trouble is i'm doing a lot of reading lately, and the excess reading can be a little fatiguing. But i can live with that.
Cheers!