Krell.... Hmmmmmmmm Good.
No, Krell is not needed, could be a bit of overkill, but what the heck if you got the bucks, go for it. Seriously, I would use a very clean, amply powered receiver, such as the flagship models from Denon or Yamaha, or better yet, high quality separates (Threshold, PS Audio, Amber (my fav), Parasound etc). The advantage to better separates is greater noise isolation, especially from tuner circuits built into the receivers, and the capacity to upgrade as desired/needed without replacing every component.