This is it in brass tacks, The M50s go low, with a recessed midrange and crystalline-like highs. The treble of the M22s is identical with a strong midrange thrown in, while bass presence, in my opinion, is their weakness. They both have their strengths and weaknesses. The M22s are sub-intended. These two speakers are exact opposites. It all depends what kind of sound your looking for. For HT, I would pick the M22s, for an all music system, I might go the other way. If your looking to cover all the bases, from what I have read, you have to slide up to the M60/M80s. That's my story and I'm sticking to it.
