So why does Stuart's conclusions list two different bit-depths as recommendations based on whether noise shaping or flat noise floor are used? I don't understand that part.
It's because you can get almost equivalent performance in the critical areas with noise shaping and fewer bits. 14 or 16 bits with appropriate noise shaped dither is pretty much equivalent to 20 bits in practice.
Not that 16 bits is horrible without noise shaping. There are very few circumstances where you need more than 16 bits for playback.
Consider that the dynamic range of vinyl (or tape) would be equivalent to somewhere between 8 and 12 bits in digital audio.
Usually when I compare a title it's one that is available in both formats from the same re-mastering, like the REM or Seal CD+DVD-A series and the Depeche Mode hybrid SACD/CD remasters.
The problem is that the mastering is almost always different between the formats, even between the layers of hybrid discs.
And sometimes the CD-layer of a remastered disc isn't remastered at all, but taken from an earlier release.
There are also cases where the CD-layer is intentionally worse mastered than the SACD-layer!
I still find the SACD/DVD-A formats sound closer to analog, which I think we feel differently about because where you find vinyl can "still sound good" I find it is usually the most enjoyable and realistic performance.
I like vinyl a lot, but I'm also aware of the technical limitations of the format. And it could actually be argued that it is the flaws in the format that makes it so enjoyable to listen to!
Like the high amounts of background noise (providing an ambiance similar to real rooms) and even order harmonic distortion (providing "warmth"), lack of channel separation (providing a artificially wider sound stage), dynamic compression (providing the appearance of more detail), etc.
From a "Hi-Fi" or technical perspective it is obviously inferior to the digital formats, but that doesn't mean it's less enjoyable to listen to.
I guess I would need to undergo a controlled dbt to see if indeed it's all in my mind, but until that time I just don't find CD to be transparent to high resolution PCM.
I don't think it's all in your mind, but I don't think the differences you hear are necessarily caused by the formats either. There are so many variables (mastering, levels, hardware, etc.) you need to eliminate to make a fair comparison that very few people have done it.
And in the few documented comparisons done so far (that I know of at least) no person has been able to tell the formats apart (under normal listening conditions).
Like in this one:
http://www.bostonaudiosociety.org/explanation.htm
Multi-channel audio and (often) superior mastering are very good reasons for favoring DVD-A, SACD and BD-A over CD.
There may also be other reasons, but so far there is very little evidence for them.
I don't believe this, because I think most high resolution masters have been given better treatment since 1999 than CD has. If they cock up the digital copy, that's okay with me.
But "Hi-Res" audio has been a niche market mostly targeting audiophiles so far.
What do you think will happen when people (artists, producers, etc.) whose only interest as far as audio quality is concerned is to make it as loud as possible start using a new format?
And there are actually quite a few cases of "loudness mastering" on DVD-A and SACD.