As interesting as this discussion is, it has become somewhat circular. Can we agree the following or at least establish whether we have a consensus on the following:
a) It is desirable to achieve the maximum possible "fidelity" in any recording process.
b) The end product (i.e. a recorded piece) can only be as good as its weakest link.
c) It is not possible to reproduce something that was not captured by the original recording process no matter how much processing power you throw at it. You can paint and polish a turd but .........
d) The original cd format was constrained by the technology of the time with regard to data storage so that the 20-20k range was achievable rather than ideal
e) That the extreme sampling and upsampling rates being developed are (perhaps) driven by marketing divisions and that the benefits of higher sampling rates, dynamics, and frequency bandwidth can be achieved without having to go anywhere near these stellar rates.
f) That if a company sells an HD music file it should be a genuine HD recording (HD at all stages) and priced honestly (i.e. reflecting actual production costs rather than as a form of market segmentation and profit maximisation).
I think back to the development of the 12" record and the point made in an earlier post about RIAA equalization. When the long playing disc was being developed there was a mechanical problem that presented designers with a trade off between length of recording and fidelity. The width of a groove varies according to the loudness of the music being recorded and the frequency of the signal. Low frequency and loud signals cut a wide groove in the disc which ultimately limited the number of grooves that could be cut and in turn the length of a recording. An electronic solution was found to this mechanical problem by cutting the discs with artificially reduced bass and then restoring that bass in the playback process. That increased the play time of the 12 inch disc to the 20 odd minutes we have today. As good as this technology can sound it can bettered albeit by sacrificing playback time. I have a Morrisey Mullen 12 inch Jazz single by EMI which has just a single track on each side which gives some idea of how the lp is comprised by storage limitations. Short of making a 24" LP I guess that not much could be done with vinyl to overcome this problem. The same is not true of the cd. Better technology and better engineering have made it possible to get more data onto a disc at a lower cost.
I for one, want to hear more (true) HD content so long as I am not being ripped off.
Geoff
BTW: Here is a not very good recording of that EMI record. Worth keeping an eye out for as it makes a very good test record.
https://www.youtube.com/watch?v=vUV2mnCCbXA