I haven’t owned MC2301’s so take my opinion with a grain of salt. I own a pair of 501’s and own an MC2012 and MC275. The MC2102 utilizes 4 KT-88’s. I believe each MC2301 utilizes at least twice that amount. In the summer months the MC2102 generated some heat. With prolonged usage the room warmed up considerably. In the winter, I welcomed the warmth, I live in NJ! It was part of the reason I went with the MC501’s. I get my tube fix with my C500T preamp. Good luck,
Mike
Mike