The front firing fan was more appropriate since the back of my cabinet is closed and the front door with a glass insert is bulged outward. I've an additional set of 120mm fans (one intake, with a filter underneath the receiver and one exhaust in the upper part of the cabinet toward the back) to renew the air inside so with this arrangement, I felt it was the best way to go. Not to mention that I wanted to be able to put another receiver on top of the Denon in case the 3 Fosi small amps I added (outside the cabinet in the back) wouldn't suffice or last for my 12 speakers setup. (6.2.4 with 4 fronts).
As far as noise is concerned, I learned how to use the T10 and actually, the speed you set in the "on" mode will be the same in auto and smart modes. I was on speed 4 wich is audible even with the door closed. I'm still monitoring the temps and now use the smart mode since the fan speed can go lower automatically. I set temp to 80 and alarm to 90, probe's oscillates between 79 and 87 depending on how loud I listen to my system. I believe it's okay this way and there's a spot to store and charge various controllers.
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