I have a Harman/Kardon AVR 325 surround-sound receiver with Polk Audio RTi6 speakers. Rock, pop, string quartets, and orchestral music sound EXCELLENT, but choral music and certain piano sonatas which emphasize mid-range frequencies sound absolutely terrible -- kind of like they were recorded from within a tin can, and as though the microphone was placed way to close. A graphic equalizer helps a lot, but it still feels like mid-range just isn't what it's suppose to be. Also, much of the mid-range problem seems to get eliminated using a pair of Grado headphones.
Has anyone else ever experience similar problems? Any advice on a new speaker system?
My musical taste is usually mellow, in a small office, without a lot of bass or volume.