what is the difference in sound from the m50 to the m60 is the m60 that much of a step up

I have the M60's. I've not heard the M50's but from what everyone has said the M50's sacrifice detail and clarity for a bit more smoothness and warmth. The M60's sacrifice that smoothness and warmth for amazing clarity and detail. Most Axiom fans prefer the clarity of the M60's, but it's ultimately personal preference.