The source material that it was most prevalent with was actually Pandora (used for convenience)... it just seems exceedingly odd for material to sound so poor on the ATH-M50's, where it did not exhibit the "flop" sound on my Sennheiser HD202's or my friend's AT ANC-7b's.  However, it does...

Hey Guys,   I've lurked around for a while but never posted; I usually could just read everything that I needed to know, but I couldn't find a good reference for this, even through search.   I got a new pair of ATH-M50s's and they sound fantastic most of the time.  However, with certain...