If you can find one, get your hands on a Audio Research 100.2 solid state amp. I have one and I love it. This amp has the great resolution of tube amps without the problems that you are concerned about (overheating in your rack). The amp does run warmer than most ss designs, but not nearly as hot as tube amps. This amp has truly amazing sound, but they tend to be hard to find on the used market. Good luck on your search
Audio Research vs. Aragon
I'm in the market to add a serious 2 channel amp in addition to an existing 5 ch. Adcom, as my new house has a large great room approx. 20'x 30' with 10' ceilings. I'll be driving a pair of B&W DM-640i's backed up by a 12" Paradigm PS-1200 powered sub, controlled by an Acurus ACT-3 pre-pro, and connected with Audio Stream cables and interconnects. I'm mainly an audiophile (jazz), but enjoy home theater every now and then. I was very close to buying the Aragon 8008BB (200 w/ch) for $2,400 when a recent visit to my local high end dealer uncovered a totally reconditioned and re-tubed Audio Research D-115 (130 w/ch?) for $1,500. I auditioned it on a pair of B&W CDM 7NT's. It sounds great, but I'm concerned about the excessive heat that tubes produce as it will probably go inside of an open back entertainment unit. Which way should I go? Any advice would be much appreciated.