The op-amps are NE5532AP, not bad, but high-end modders probably would replace them.
If time allows, I'll try it on two channels and see if the result justifies the effort
The DA converters are 18-bit Phillips TDA 1305T, not big in numbers, but great in sound
And they have a good reputation by those capable of listening to the growth of grass...
AD converters are SAA 7367T with up to 18 significant bits, same as above regarding quality.
The box has a two part powersupply - the wall-wart transformer and the stabilizer inside the box.
It's the latter that's responsible for the heat. The regulating circuits are mounted on an alloy cooler, which itself is directly mounted on the bottom of the case.
You can improve heat dissipation a lot if put the unit flat on a large metal part (preferably alloy, 5-10mm strong).
In a rack mount it would be best if it's the top unit with some space above, but mount it upside down to improve heat flow
It's a really strange design to use the PSU as a heater BELOW the active circuits
Imho it's totally safe to operate it without fan if one takes care of the above points.
cheers, Tom
