You can add fan it will not degrade the sound, but it will add fan noise to your room.
Is your reciver in a cabnet or on an open shelf??? What kind of air flow is there around you reciver?? John
I have a marantz 4500 receiver and the problem is it gets too hot because it is designed for 6 ohm speakers and my front speakers are 4 ohm so I added 2 ohm registers to each of the front speaker and it helped a little but now I am wondering if I can add 80 mm fan on top of the receiver.
Will the magnetic field of the receiver will effect the sound ?

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