Initial impressions: The Grant Fidelity sounds very nice, even with only a few hours of play time. The PS Audio DAC is amazing! Very smooth, clear detailed sound right out of the box, very impressive. Also, switching from the TGP-IV to the Ultimate Receiver II as a preamp with either DAC the sound stays the same. This contradicts previous experiences without an external DAC.
I first plugged in the Grant Fidelity directly into my 225x5 and didn't like it, switched mid song to the TGP-IV as the preamp and noted an immediate improvement but that was with zero play time on the unit through the tube output.
I still need to burn in the Grant Fidelity and do some more equipment swapping before I do a real evaluation. One thing for sure though, both DACs seems to be a notable improvement over either Sunfire pre.
Klipsch RB 75's
Klipsch RC 64 II
Sunfire TrueSub Signature