Can someone recommend how much wattage,  at what ohm level,  I should need to drive a pair of HD650's  ???   I'm not looking for an amp brand recommendation,  just the amount of headphone amp output power, expressed in watts or milliwatts,  and at what ohms.   Thanks!   John

Hi All,     I'm looking for recommendations on how much power is required to drive Senn HD650's, which, as most of you probably already know, is rated at 300ohm nominal impedance.  I like listening to a pretty eclectic range of jazz, rock and symphonic, but typically listen at fairly loud...