Need verses want verses do they work?
I would say there is probably no NEED for an external AVR cooling fan in most situations.
You may want one just because its not a bad idea to exhaust heat away from electronics you wish to last a long time. When I bought my newest AVR, I decided I wanted it to live a long comfortable life so I bought an external cooling gizmo for it. It is practically invisible as its made to sit right on top of the AVR and blend in.
Its silent. It turns itself on and off when it senses heat above a certain temperature and it sucks the heat away from the AVR.
Do I need it ? Nope. Do I like it ? Yes I do.
AC Infinity AIRCOM S9,. Wonderful little device.
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