A lot of people, including myself, would not consider the M50 to be an upgrade from the M22, I have heard both and own the M22, I much prefer the sound from my M22's. The M50 have a more laid back midrange while the M22's have less bass. However, with a sub, the bass gets picked up by the sub anyways.

An upgrade from the M22 would be the M60 or M80.

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