Lol it cost a HEAP spent over 140K easy... Kinda stopped costing it all... The rack is all fan cooled by 120mm and 172mm 12V fans... The latter moves 300cfm. The setup is an elaborate daisy chain from a THX pro logic reciever, which means I drive the whole lot from 1 remote. The SL-Q3 is awesome... In that enclosed space yet never develops howl from the bass etc. This system started in 1989