Comment by pmg | Hacker News Reader

Comment by pmg | Hacker News Reader

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Keen.

Sony was originally proposing 44.056 kHz (NTSC - popular in Japan) with 16 bits while Philips was pushing for 44.1 kHz (PAL - popular in Europe) with 14 bits. The two reconciled their differences at the 4th Red Book meeting in 1980[1]. Sony was further ahead in developing the CD players but Philips supposedly was in the lead when it came to making the CD's[2]. Sony insisted on 16 bit vs while Philips was pushing for 14 bit. As a compromise they may have gone with the 44.1 kHz Philips was proposing and the 16 bit Sony was proposing because it would be easier to remember. Posts [1] and [2] are in direct conflict with each other on this point. There was further tension over what size disc to use [2].

The CD was one meeting away from launching another format war in the spirit of VHS vs Betamax or Blu-ray vs HD-DVD

Of course 44.056 kHz products did make it into the field for professional audio engineers. Anecdotally this made for some trouble: http://www.realhd-audio.com/?p=2197

[1] http://www.exp-math.uni-essen.de/~immink/pdf/beethoven.htm [2] http://www.whathifi.com/blog/the-cd-is-30-years-old-today

Quoting your first link [http://www.realhd-audio.com/?p=2197]...

❝Of course, lots of CDs were released with the original 44.056 kHz rate simple reclocked at 44.1 kHz. This resulted in a very slight speed increase AND a pitch shift of less than a quartertone.❞

While technically true (less than a quartertone), it's much, much, much less than a quartertone. It's 1.7cent (1.7 percent of a half-tone, or 1/30th of a quartertone). If you accidentally mix up 48kHz and 44.1, it's a much more noticable 1.5 half-tones. I doubt that this slight detuning is so blatantly obvious that it "feaks out" even a very well trained and very hot tempered classical violinist.

If you want to check the math: There are 12 semitones in an octave. One octave doubles the frequency, so the frequency difference between two adjacent semitones (e.g. from any key on your piano to the adjacent white or black key) is the twelfth root of two: ~1.0595. When tuning your guitar, your tuner might display the deviation from the true tone in cents, that's 1% of the interval between two halftones, or (python) math.pow(2,1.0/12.0e2) -> 1.0005777895065548.

Frequency ration between 44.1 and 44.056 kHz is 1.0009987.

Here's what happens when you do mix up 44.1 khz and 48 khz. Van Halen - Jump (Greensboro): http://youtu.be/Mjx_GjyXCs4

Quite a lot of early CD players were actually 14 bits. Many early CDs were probably mastered with 14 bits in mind too, as they have a noticeably low average mix level.

That makes no sense at all. A 14-bit player would play the top 14-bit.

Playing the bottom 14-bits would make anything with nonzero top two bits sound mostly like noise.

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