I hear a lot about how dark the hd650's are etc. And I hear the term neutral tossed around often when comparing to other headphones (akg k 701). But let me ask you, when you say SSSSSSSSSSSSSSStuff, there is no grating sibilance no matter how loud you say it, I couldn't care less if your headphones are flat if they emphasize a grating sibilance, you can chock that up to the recording all you want, but what I hear is that the hd650's are NATURAL.
When you hear bass, it is not always tight and defined, some artists intend their bass to be heavy hitting, while other music, like jazz, demands a tight string pluck defined.
I feel like the hd650's can do both, while cans like akg k 701 can only do 1.
Natural natural natural, loving my hd650's.
-A R