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[TotalSonic]

Regarding history of the development of the Compact Disc -
check out

 http://www.opticaldisc-systems.com/2003sep-oct/Evolution42.h tm

&

 http://www.opticaldisc-systems.com/2003nov-dec/Evolution52.h tm

for some truly excellently researched detailing.

From these articles here's an excerpt:

  It is as well during this ultimate meeting that a legend about the CD Audio was built as what the playing time should be. Of course playing time is a factor that has a direct influence on the diameter of the disc. No doubt that changing quantization from 14 bits to 16 bits would cause an   increase   of   data   to   be   stored   with    immediate consequence  on  the  diameter which initially had been set to 11.5 cm. Why such a strange figure? Because it had to be small and pragmatism was the rule. At that time the audio Compact Cassette was very popular and store clerks were used to this very convenient format which became a kind de facto standard for shelving. Its biggest dimension being its diagonal of 11.5cms, Philips decided to make this size the standard diameter for the CD. Goodbye the 10 cm requested by Lou Ottens. In 6 years the small disc grew. Logic isn?t it and in fact its growth was not yet finished. The original idea that governed this size was a playing time of 1 hour which is quite enough as the major part of music catalogue doesn?t exceed this value.
  A legend tells that it is the wife of Akio Morita who would have advised to her husband, close friend of Herbert von Karajan, to make sure that the CD can contain the Ninth Symphony of Beethoven in its entirety when conducted by the maestro of the Berlin Philharmonic Orchestra and played in 74 minutes (supposedly). It was then out of the question to deprive the maestro of such an honour while he had been an active defender of the Sony digital PCM technique and will become later on the most famous evangelist for the CD. Thus 5 mm were added to the disc diameter for Ludwig van Beethoven and Herbert von Karajan. But this legend is based on an error.

 It is also said (as reported in the Sony Genryu book) that Norio Ohga, a trained musician who had studied music at the Conservatory of Berlin, drew the attention of the join team on the fact that 95% of all classical music pieces would fit onto a 75 minute disc. And to guarantee this playing time a 12 cm disc was necessary. But there is another story reported by Philips which says that Norio Ohga was an aficionado of the Ninth Symphony and after some researches he found out that in the performance by the Berlin Philharmonic Orchestra conducted by Herbert von Karajan lasted for 66 minutes. So 1 hour/11.5 cm was not enough. To be sure to operate the good choice, Philips asked its subsidiary, Polygram, to check what they had there. They discovered that the longest known performance of this piece lasted 74 minutes and had been recorded during the Bayreuth Festival in 1951 (EMI recording in mono) and conducted by Wilhelm Furtw

[Romy The Cat]

C-J wrote on Sun, 11 December 2005 22:39

ONE reason was that it was "almost" impossible for the 1-bit delta-sigma modulators to provide a larger dynamic range ....

Yes, among engineers there is a strong feeling that the multibits are more superior. Still there is mystery that I cannot figure out. Over the year I had all imaginable DA converts, including the multibits. They were not only all imaginable but the best converted ever produced. Furthermore, those converted were place in playback and exposed to the subjective evaluation that were not even remotely imaginable for the most of the manufacturing and designing houses. What I meant was that I really-really wanted to push the converted and paranoiacly find something that would be… at least in the same domain as my analog. So, without know anything about the filtration types, processors types and sampling type what I been using for year so far. The damn 1-bit invented in the very beginning of the 90s (modified Bidat). The irony that I get annually 2-4 DACs the different people bring in my listening room trying to see if this new DACs would be able to stay next to Bidat. Surprisingly the Bidat keep destroy any competitors year after year. As I understand the Bidat is a primitive Philips 1-bit…

I am sure the if we objectively measure Bidat and compare it with what a good multibit dose then most likely the Bidat will looks kike a jock. Still it sounds quite remarkable… Unfortunately it dose not do higher the 44.1k

So, is it the type of the bits processing or the specific implantation of a given topology? The answer is pending…

Rgs,
Romy the Cat

[locosoundman]

The sampling rate on the CD comes from the need to store digital audio on video media (since there was nothing else with the necessary bandwidth in those days.  The 44.1 kHz sampling rate comes from the frame rates of video - I forget the exact numbers, but 44.1 kHz works with both formats.

I also used to believe the urban legend, until I found out that due to the coding scheme and error correction data, less than half of the data on a CD is actually audio - I think it is actually closer to 1/4th.  If they really wanted to cut corners they could have done it in the bit depth or the overhead.

Great chapter in Pohlmann's book about it - Watkinson's book as well.

Best,
Rob

[zetterstroem]

after owning a non-oversampling 18bit multibit dac with no digital filters for over a year now i actually think the way to move forward is to stop the race and find out more about what actually sounds good...  

i don't think we need more than 16 bits.... i don't think we need more than 44.1k....

we need less dsp to smear the sound..... and no src either.... it may make it easier to connect and use but it compromises sound quality....

better analog stages...

and then of course better software etc.