Forgot to mention that the main unit of the EF1000 also runs quite hot (mainly from the Pre-Amp tubes) and if you are in a small room with it (as I am) even with UK Summers it can get very hot in the room if you don't have A/C or at least an open window with a fresh air breeze coming through on to your body to give yourself free evaporative cooling. This is the only down side / negative comment I have against the EF1000. It has so many positive sides that this one negative side I can easily put up with on and off (UK weather dependant) over just a 4 month period of the complete year.The EF1000 was re-designed and re-built by Hifiman specifically for the Susvara which is the main reason why I bought one together with the Susvara as a combined package at a reduced cost. Its an awesome Integrated (Pre & Power) Amp which can also give fantastic performance with Speakers.
The AC to DC Power Supply unit of the EF1000 only gets warm even in the UK summer months.