Have you heard the HD650? They are detailed and 100% non-fatiguing, not sure if the meridian will be able to power them properly.
Actually... let me check.... I have both...
EDIT: Oh yes, that will definitely work. Very impressive PRAT, drive and bass definition for such a puny device! Sounds great! Get the HD650, you should definitely like those with the Meridian Explorer!
Many people like HD 650 and 600 with just Explorer, apparently it can drive them well. I haven't heard the HD 650 but HD 800 seems so cool, and people say it sounds amazing so they kind of seemed like the king of all headphones to me. :) I'd better take the Meridian Explorer with me, go to the Sennheiser dealer and try both of them. Thanks for the recommendation.