Oppo as a pre/pro

I have had a 105 for over a year. Used it as a source, as a Dac with a separate transport and PC and as a preamp. I have several friends that use the 105 as pre/pros in secondary systems. For me, the 105 on it's own falls short but with a stereo tube buffer between it and the stereo pre/amp does a remarkable job of selling the music as if it was coming from real people and real instruments in real space. Does so better than my (now sold) all Krell HT did. The 105 with a buffer seems to yield the strengths of digital and of tubes without their weaknesses. Lot's of paths in this audio world. Enjoy, be patient and best of luck!