First I have to admit that I don't know much about digital techniques. But after reading (part of) the – awfully detailed and repetitive – article (http://www.iar-80.com/page38.html
) that Pepzhez
has brought into play, I must agree that theoretically the SACD format, which I always have sympathized with, has some problems with high-frequency amplitude resolution.
It's not accurate, as the author did, to speak of «64-fold oversampling». In fact it's a true sampling
with 2.8224 MHz, not sort of interpolation. And that's exactly the 64-fold of the redbook sampling frequency of 44.1 kHz, therefore 6 bit at 44.1 kHz. As a consequence, the 1-bit system has 128 steps at its disposal for a 22.1 kHz sine wave (corresponding to 7 bit), 176 steps for 16 kHz (corresponding to 7.47 bit) and 256 for 11 kHz (8 bit). I really doubt this is enough and fear it could have serious consequences for the sound.
Myself I had a brief audition shortly; the SACD layer sounded clearly better in terms of overtone reproduction (of a cello) without having any shortcomings compared to the CD layer. This must not mean that the above mentioned has no relevance. For it's clear that the extended bandwidth brings a better articulation and transient response. (This despite the author's explicitely opposite standpoint). But in fact there could be some flaws which might only appear in comparison to a more accurate and better resolving system than the CD, i.e. DVD-Audio. I really can't deny this possibility.
Although I find it impossible to struggle through the whole article, I got the impression that the reviewer (J. Peter Moncrieff or who?) has done a very serious listening and knows what he's talking about. Just one objection: I have'nt found any declaration of the decoding (DAC) equipment, just «...played back through the professional master digital decoders of the two competing systems» – as if these must be taken both as the nonplusultra of their category and therefore free from any influence on the sound. But that's the only obvious point of criticism I have found in this review. So I must confess that I'm a bit shocked... I guess I have to take this article seriously. But what do I know in the end...
Is this the time to swap to DVD-A?