For anyone wondering how the jitter is so squeaky clean on this older device. They used advanced (ESS Sabre-like) ASRC to get it so. Found the details here (dutch article):
https://www.hifi.nl/recensie/3628/Cambridge-Audio-DacMagic.html
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Hi, again, Veri -- Thanks very much for this reference! It led me to an even more useful CA White Paper at
http://www.auditionveritable.com/840C/840C White paper.pdf that clarifies a lot about the up-sampling but also raises a couple of (ignorant?) questions:
1) If I understand the block diagrams correctly (have to study this WP more closely), the
digital up-sampling is done between the digital source and the DAC chips. Right? If so, it makes CA's de-jitter solution completely separate from the post-DAC
analog output filtering. Yet these disparate functions serving distinct purposes seem often to be discussed as though they were a single unit. Or do I still have it all wrong?
2) I think I recall that decent CD players have typically "up-sampled" (read, replicated) the digital source and run their DAC chips at a higher rate to make it easier to apply a sharp analog filter before the analog output stage. Maybe the only essential difference here is the quality of the up-sampling technique that CA is using in this unit?
3) Since newer DACs, which are also measured to have very low jitter noise, seem to have no such careful up-sampling mechanism (or at least don't trumpet them), how do they get rid of the jitter that presumably comes from largely the same timing issues in the source? (The CA WP cited above seems to outline a couple of other approaches, but I didn't fully take them in) Is there any reason to conclude that one approach is superior to another?
Since the CA DacMagic Plus is still on my short list, it would be helpful to me to understand this better. Otherwise the Topping D50s (for example) seems superior in every way, given I don't need balanced outputs nor a less than perfect headphone amp. -- JClarkW