With the Backert preamp in the system, I then returned to using the AGD GaNFET amps. While the difference between the tube amps and the AGD amp was relatively small in my original reference system. before the addition of the Acora speakers, Synergistic Pink fuses, PowerCell8 SX, Auva footer, and the Backert preamp, each of these additional components increased the resolution of the system. Together, with the fast speed and high resolution of the AGD amp, the music crossed the line, becoming too analytical and almost piercing in the treble. This is not to fault the amp. I simply have to back off the resolution by removing some footers, changing a fuse, or even rolling tubes in the Backert preamp. That will be my personal adventure in the coming weeks. I'm sure it is doable and there is no need to take you down that trail in this review. That's the fun of fine-tuning that comes when you're this close to perfection.