Well, there is a major difference in clarity. The M50s tweeeter is much sweeter, and cymbals sound like my son's do when he plays his drums. I haven't had much time with the speakers yet, but initially the bass semed about as deep as the old Toshibas, and I sort of expected more. Nonetheless, the more I listen to the M50s, the more I like them. The M50s also play louder, and without strain, even though I will not push them until I get my new receiver this week. That's also when I can try the Qs4s!
