"Wojtas G." wrote in message

I'm going to buy a new shelf unit for my audio set and I'm not sure
that this one will ensure proper cooling conditions for my amplifier.
The max spacing between the top of the ampifier and the shelf above
will be about 1,5 cm (0,6"). The rear and both sides of the shelf
unit are open so the amplifier will have a lot of space around
itself. The amplifier's power is 6x75W RMS and the nominal power is
290W.

Will these conditions be good enough to ensure proper air circulation
and cooling of my amplifier?

Nobody can tell from what is provided here.

The speakers you use, and the power levels (i.e., sizze of room, speaker
efficiency and personal tastes in loudness) and type of music figure into
estimates like this.

A Trevor pointed out, the type of cooling in the amp, whether convection or
fan-induced also matters.

Rule of thumb is leave 2-4" around a power amp on a shelf.