I assume a break in period is required for a final comparison to be fair, but I'm interested in your subjective opinions as to the differences? Is one more bright or warm than the other? Is one more detailed or higher-res than the other? Do you have a personal preference from one to the other? (I understand this is all subjective, but I'm interested in your findings!)
I will answer to all these.
First, while I believe in burn-in regarding headphones and speakers, I am more sceptical about electronics. From my personal experience, I never noticed any audible (or measurable) difference during the break in process. My opinion, for what it worth..People simply get use to a specific sound and believe this one has changed after a period.
That's being said,
About CDP-9 vs DAC-9 (both paired with double mono STA-9s, XLR connection, speakers: MA Silver 10s, files: 16b/44 WAV or 24b/88/96 or CD)
CDP-9: Overall has a flat sound, I haven't noticed some kind of emphasis on any part of the spectrum. I guess it's close to neutral. Doesn't have the typical Sabre signature, not specifically bright, cold or analytical. More rearward and narrow soundstage. Imaging is more precise and focused. More air between instruments but sounds a bit "empty" and thin for these reasons. Bass and low mids are better textured. Highs are maybe a bit roll off and smoother. Overall, I would say it is accurate but a bit "boring" in the other hand.
DAC-9: Definitely warmer. Wider and more forward soundstage. Fuller, more organic presentation. More impact and deepness in low frequencies. Faster and stronger midbass. Sounds thicker. A bit more like a V shaped signature overall. Lot of punch, yet still enough refined depending of the style of music. Remind me the Cayin house sound. As far I'm concerned, I prefer this kind of signature but this is clearly not neutral.
At the same level of volume, DAC-9 is no contest louder. However I prefer to have a margin for precise volume adjustment.
Conclusion: I prefer the signature of the DAC-9. I will return the CDP-9 and wait fir the release of CDT-8 (hope this one will have an AES out) or another CD transport.
A word about the headphone amp:, overall neutral and very good. Enough power to drive my K712 Pro fine. I doubt this will have enough juice for very low sensitivity headphones.