InfoSponge says his room is very reflective. Of course this means some frequencies are reflected back, and other frequencies aren't as much. If he were to play music softly enough that the sound didn't bounce off the walls, maybe he wouldn't have to worry about equalizing the sound. But I imagine in his 15 x 20 with a 21 foot highly reflective listening room, they'll be plenty of sound bouncing about, in some of the higher frequencies. While equalization alone can't solve all the problems caused by bouncing high frequencies sound waves, it should tame those frequencies somewhat in his listening room. A better approach would be to treat the room itself, but for aesthetic reasons, Infosponge said earlier that "acoustical treatments are out."

Best,

Will