@folkfreak Thanks for taking the time and effort to do the comparison. Your findings are helpful and add to the discussion. A great read also!
I was wondering how your comparison was going (this very morning) while reading Positive Feedback’s ’revisit’ of the Prism Sound Callia DAC. Highlighting some takeaways here, by the author Larry Cox, who compares the Callia Direct vs via a Pass Labs XP-12.
[Note: my focus is around the ’notional’ and not the DAC itself]
"Connecting the Callia to Pass Labs XP-12 transformed the sound....The Callia Pass Labs XP-12 combination added a measure of warmth with an increased humanity being presented....with a fuller bodied preamp, like Pass Labs’ XP-12, the Callia transforms into a richer, fuller bodied DAC that is delightful."
Article here:
https://positive-feedback.com/reviews/hardware-reviews/prism-sound-callia-2/My own experience finds that adding an active preamp injects body and richness and a ’completeness’ to the music that brings it closer to what I experience with music in person. Larry sums this up as "warmth not added but ’realized’."