On October 19, 2019 at 10:51, highfigh said...
If the bottom is vented, the top may have a vent, too. Otherwise, active cooling would be fine and those can be 1RU high.
Top and bottom probably do have venting, but those become "side" vents in this case, and that creates a trap at the now top.
I would want something pulling air through, as I think without, the life of an amp will be shortened.
