zuio I went through this EXACT dilemma recently, my firstwatt f7 in my small non air conditioned bedroom in hawaii was not useable due to heat but it sounded so good. The amp replacement that made me happy is the Folsom TD7297 diy amp pcb and folsom antipole psu, it's a 15 watt class AB amp. You can have a builder make it for you, such as Radu at simpletubepleasures. It makes no heat and sounds as good as my firstwatt, with even more dynamics
Low heat alternative to FIRSTWATT J2 ?
Any Gainclone or Class D or battery power alternatives available? I like the crazy good micro dynamics and rhythmic cohesion of the J2. My speakers are 93db full range. Also interested in AMP/DAC combinations like the devialet or NAD D7050 that meet the J2 performance (those 2 mentioned don't)