At 16:19 27/5/2013, Sampo Syreeni wrote:
In that debate, I'd take a look at the Acoustical Reneissance for Audio position paper, aimed at influencing the rates and bitdepths of DVD-A, at the time. (http://www.meridian.co.uk/ara/araconta.htm) The limits it sets out says 48k is mostly enough, 56k is most certainly okay for anything and everything, so that of the commonly used rates at least 88.2kHz minimally covers it all with a large margin. It also makes it clear that 24 bits at that rate would be much more than necessary. Many fewer bits suffice, and if you think about the final distribution format, where you can apply in-band noise shaping willy-nilly, as few as 12 bits might just suffice.
Correct me if I am wrong, but it seems to me that the reference in this documents to "12 bits" concerns an already packed signal, which needs to start off at a higher bit rate. The BBC did a study years ago and I seem to recall that they decided that the worst case was the dynamic range of big band jazz which, they determined needed 20 bits of linear PCM. Of course, everyone knew that 16-bits was chosen for CD because it was cutting edge state of the art in 1980. As far as sample rate is concerned, I agree about 48kHz before sampling, but there are a lot of 15ips tapes that sound excellent but which hardly made it to 20kHz.
David _______________________________________________ Sursound mailing list [email protected] https://mail.music.vt.edu/mailman/listinfo/sursound
