One suggestion from one source, totally anecdotal, non-verifiable, and as you state "not double blinded AB" does not constitute some known data.
We can determine:
The specs of the Oppo are comparable if not a bit better than the XSP-1 and the noise floor of the Sabre DAC @ -135dB is not bettered by the XSP-1.
There is no known problem or quality issue with the digital volume control on the Oppo-105.
Other devices connected between the Oppo and the power amp are most certain to color the sound in some way. In many cases this change, or reduction in transparency, will be pleasing to the listener, especially the one whose funds acquired said devices.

















Ok, let's take a shot at other factors: By adding a pre-amp, you are definitely altering the audio in some way. I don't believe any pre-amp is completely neutral. And this is NOT necessarily a bad thing. For example, some people like the distinctive McIntosh sound. This is coloration added by McIntosh equipment. Other manufacturers have their own signature sound. Even different types of equipment (tube vs. SS) produce different tones. It could be the coloration added by the Emotiva pre-amp was preferred to the person who did the testing.
Classic indeed!!! I wondered about this phenomenon myself that going direct to the amps sounds worse than going through a pre-amp. Definately, the 'colored' sound of the pre-amp is the reason for the 'improvement' in sound... a very subjective observation indeed.








