I've never heard either one. But since you have them both your best bet is to put each one into your
primary system and report back. I've played with way too many mid range amps over my 30 audio
history. All in all, aside from a few standouts, most amps at that price range will probably sound the
same. I know some will argue that but again, at that price point most will sound very similar.
Listen to each for a couple of days or even have a friend swap them out...blind test. Glaring, obvious
sound characteristics may quickly reveal themselves or it could be much harder to tell one from the other.
I guess I would probably lean towards the Carver because its THX certified. At least it has the power/reserves available if needed. Completed ebay sales have very few Carvers but quite a few Kenwood M2s. A couple of midrange standouts I've heard include Odyssey Stratos, Jolida 302, A couple of Hafler PA amps too (yup, not all PA amps are junk. I have a couple of other recomendations from this arena but too many audiophiles poopoo PA amps). Good luck and let us know. Based on specs/history/my own personal (unfounded) opinion: +1 for the Carver.