Bertram - with the KEF LS50 and the Hegel at your office, how do you get any work done?? :) I have had this pairing for a few weeks now, and I am very impressed with the Hegel 80 - clear, powerful, transparentÂ…it just seems to do everything well. Nothing is emphasized, which is exactly how I like it. If anything, it's ever so slightly on the warm side of neutral for a SS integrated.
I have had a similar experience to you with the volume setting, until I tried the balanced inputs. With the RCA connections I heard relatively little coming out of the amp until I got up to 30 or so on the Hegel, and I really had to be around 46-50 for good, clear sound. I attributed this to the low sensitivity of the KEFs, but It was a bit frustrating in that it seemed there was a very small range between "too quiet/background music" and "the neighbors are going to hate me."
However, since my Oppo has balanced outputs I decided to try a JW Audio signature balanced interconnect and the soundstage just exploded, the separation of instruments was starting, and the volume range from about 30-45 was nicely adjustable. There may be different gain for each connection, but even when I adjust for volume levels the balanced connection is significantly better. I have another pair of balanced interconnects coming to see if it's the balanced connection that makes the difference or the particular cable (or some combination of the two).
However, right now I could be happier with the sound that I'm getting. Oh, and the Hegel DAC is a very solid performer. If you only use computer audio, get a good cable, the Hegel, and the KEFs. For about 4K, you're not likely to get better sound anywhere.
Overall, though, I significantly prefer the Oppo for DAC quality, for versatility, and for the fact that I can play DSD files.
Hope everyone is well,
Scott