What are some albums that are absolutely transformed when you get new (read: better or different) headphones?
69 Love Songs (Magnetic Fields) It just gets clearer and clearer.
Experimental Jet Set Trash and No Star (Sonic Youth) Going to Orthos makes this album feel like a night with the band.
Stunt Rock Vol. III (Stunt Rock) (this is a low quality recording to begin with, but it's better with HE-500) Ortho separation mostly.
I put this in Headphones because it's less about the music than the way it is transformed by the quality of the headphones.