I agree recommending Crown. Take the Crown K2. It has no fan, is absolutely fantastic for bass amplification. I use it in bridged mode for my Wilson Audio WHOW subwoofer. For Krell you surely pay much more but you may get less.
Which Krell for driving subs?
I now have Krell monos for the main panel of my Audio Artistry Beethoven Speakers. For the subs (operats in 20 to100Hz) with 4 12iches in each cabinet I need at Krell stereoamp. I can spend 3500usd on this amp.Which amp should I choose?