Pretty well any amp will make M22 shine, except cheapo amps.
A tube or robust amp is the best. I started with a mid range Onkyo TXNR525 was great. Up graded to a Tascam PA-R200 with THX 2 and toroidial transformers. and it was noticeable a lot more detail to the point of " I never heard that before".

The sub and M22 is a must they are great alone, but my M3s have more BASS without a sub than my M22s. If possible highly recommend one.