has any one in this forum encountered the Nyquist Theory? Its pretty damning - essentially digital needs to sample at around 20 times the current rate to preserve the true nuances and "life" of the original performmance
You're confusing two things, Nyquist doesn't state anything about the life or nuances.
Nyquist-Shannon simply states that when converting from an analog signal to digital (or otherwise sampling a signal at discrete intervals), the sampling frequency must be greater than twice the highest frequency of the input signal in order to be able to reconstruct the original
perfectly from the sampled version.
Now that doesn't imply, for one second, that all A-D / D-A processes are perfect - they are not.
The second bit of your quote is a different discussion and depends on whether you feel our hearing is capable of listening to the same frequencies that bats can.
In my view this is a red-herring, the issues relating to audibility of effects that take place above 20kHz are solely due to effects ultimately occuring within the audio band.
That is, in my view, you cannot hear above 20kHz, but you may well be able to hear the effects
on your audio equipment of signals above 20kHz.
It's not the same thing and I don't believe CD is inherently bandwidth limited for the function it needs to fulfil. It may well be too limited in terms of dynamic range though and this is where I would concentrate my efforts.
I suspect we're fighting a losing battle though, with the era of data reduction. Look at the quality of FM radio, an effective data rate reduction of almost 7 times in the move from FM to DAB.
Andy.
i've come to the conclusion that there is little difference qualitively between vinyl and cd. vinyl has certain advantages in that various recordings sound better on it (the riaa issue imho) and that some recordings are more easily available for vinyl. cd's are far more robust and convienient and also some recordings are more easily available for cd.
