Active Loudspeakers.

My reading of this is it isn't quite so simple as electronics in a sealed box.  The two black rigs on the back above the heat sink are bass ports and these are open to the inside of the cabinet and the outside air.   When the speakers are operating air will be puffing in and out, and will to some degree provide ventilation by virtue of the pressure variation within the cabinet.  The heatsink provides cooling to the power amplifier.

I don't reckon that the puffing air, in then out etc. provides any cooling at all. Also the large power supplies needed create large amounts of internal heat. I think that the design is flawed.

www.youtube.com/watch

Z.

No Z, they work just fine. You need to remember these are class D amplifiers, so do not dissipate much heat as they are very efficient, and the power supply is a switchmode type so again very little heat. The dissipation of one of these is probably only 100W, even though the amplifier may produce a kW or more RMS. Technology rules! Failures of reasonable makes are very rare, and they monitor the temperatures anyway and will reduce power if a problem is detected. They are all networked with Ethernet so report the status continuously to the operator.

No Z, they work just fine. You need to remember these are class D amplifiers, so do not dissipate much heat as they are very efficient, and the power supply is a switchmode type so again very little heat. The dissipation of one of these is probably only 100W, even though the amplifier may produce a kW or more RMS. Technology rules! Failures of reasonable makes are very rare, and they monitor the temperatures anyway and will reduce power if a problem is detected. They are all networked with Ethernet so report the status continuously to the operator.