My apologies to everyone else on this this thread. Hopefully we quickly deal with the above issue then move on
Shame on you. Shame on you. As a qualified Audio Engineer you should know better. The standard “Red book” CD format which is what everyone buys from the store uses a 16 bit Pulse code modulated sample with a 44.1kHz sample rate for 2 channels.
Due to Nyquist Aliasing the greatest frequency that can be recorded is 22.05kHz which is within the range of some humans hearing. At this frequency all that is presented is a pure square wave, basically a Dalek on helium. It is only at the 11kHz range that one can even begin to attempt to approximate the shape of the sine wave. This is within the hearing range of most humans. At this frequency even small quantisation effects can have a big difference on the wave being represented. Also any clock freqency shifting will have discernable effects on the audio signal. When in these regions there is also artifacts created by converting high frequency square waves into sine waves that have to be dealt with. All combined, this affects the tonal quality of the note that is reproduced and does nasty things to the harmonics of the note. The basic problem has always been that CD format is a digital approximation of an analogue signal.
Most people cannot or do not want to notice these effects. But you, as a qualified audio engineer, should be able to hear them. The easiest way to solve these problems would be to increase the sampling rate. The original rate of 44.1kHz was inherited from a method of converting digital audio into an anologue signal. This has to comply with the NTSC and PAL video formats. The other option would be to increase the PCM data to a 24 byte sample. But 16 bit was again chosen for historical reasons and so they could get all of Beethovens 9th symphony on a single disc.
From what I can determine the real reason for changing from vinyl to record is that a record cost $2 to make and they could sell it for $20. A CD cost $1 to make and they could sell it for $40. Therefore an increase of profit per record to the record companies of 117%.
If you want to discuss this issue further, may I suggest creating a new thread. As to who am I, besides being the writer of the Quest system, a professional entertainer and an ex-radio announcer, I am also a physicist who is currently doing nuclear research for the University of Waikato. I always love to chat about basic physics.
