This weekend I hooked up my new Proceed HPA2 to my 3801 for the front L/R speakers and after connecting everything I power the system up. The 3801 was at minimum vol (-60db) and there was no sound. I slowly turned up the volume and still no sound. kept turning and turning slowly with anticipation and no matter how much I turned there was no sound. Now I was almost at 0db and I heard the music really soft I kept turning until I reached max vol (+18 db) and still the music was only softly audible. Powered everything down rechecked the connections and still the same problem. After reading through the manuals, I thought that my 3801 didnt have enough juice (1.2 V @ 10K output impedance) to drive the HPA2 (1.56 V @ 11K for rated power). Duh what a jackass I have been buying a state-of-the-art amp and hooking it up to an average preamp and not even being able to drive it listenable volumes. I almost broke my back getting the 100 lb behemoth up in my rack only to have to take it out. For one last time I rechecked the connections and I found a small switch behind the amp to switch between SE/Balanced inputs. I almost kicked myself when I saw the switch in the balanced position. Stupid me. I switched it back to SE input and re powered the system and as soon as I turned the volume past -60 db there was music flowing thru my speakers like never before. I turned it upto -20 db and it was LOUD. I switched off my sub because the bass from this beast was so tight and powerfull that my velodyne became the weak link in the sound. The sound stage was way beyond the speakers in length and breadth and each instrument had an attack to it. I was in audio heaven thinking that if the amp is doing such a good job on my mediocre Infinities then what would it do with a nice set of speakers like the B&W. Now I want to upgrade my speakers and possibly integrate a two channel tube preamp into my system for two channel listening. God!!! this hobby is draining me out. Ok now for the worrisome part. On my way to work this morning I was thinking that if the switch on the back of my amp was in the balanced position while my preamp inputs were going to the SE side why was there any volume at all from the amp at max volume? Shouldn't it have been dead silent at any volume as there was no signal going through to the balanced connector? Does this mean there is signal bleed through between the two types of inputs? Some one please help me clarify this thing as it is driving me nuts. Or if someone with SE/Bal connectors in their amps can verify this. Thanks everyone.