Dear @fleschler : I know is inferior to the AU-1000 and probably your Audio Interface is even better at least yours has wider frequency response and this says a lot:
https://audiokarma.org/forums/index.php?threads/audio-interface-cst80h-step-up.866712/
I don't know why you could go for the Zesto when your Audio Interface is one of the best out there and I don't " see " how the Zesto can beats it, but........
Btw, I think that is improbable that a Zesto owner already tested against the SUT's you ask for.
Anyway, always great fun testing audio items.
R.
https://audiokarma.org/forums/index.php?threads/audio-interface-cst80h-step-up.866712/
I don't know why you could go for the Zesto when your Audio Interface is one of the best out there and I don't " see " how the Zesto can beats it, but........
Btw, I think that is improbable that a Zesto owner already tested against the SUT's you ask for.
Anyway, always great fun testing audio items.
R.