I've got 60w dynaco mkiiis running the tops of my VR4s (89db), and a 170w power amp running the bottoms. The power amp has potentiometers for each channel, which I turn down to a little less than half and keep them there. (You can accomplish the same thing by other means). I've used a passive pre to good effect, but currently have them running through a Juicy Music Peach II. It sounds great, and I love the tube/ss combination. I change the flavor of things by switching out the power tubes in the monoblocs from time to time. No way I'd sell those VTLs.