I'm listening to Grado SR-325's right now with the Grado RA-1 amp. Too amazing. The Senn 600's are also excellent (also driven by the RA-1 but with the knob cranked), but the Grado's seem to put me right into the music. If you don't mind things in your ears and can be isolated from your enviromment, Etymotic ER-4s canalphones are totally accurate and sound wonderful.
