On Sun, 6 Mar 2005 20:31:24 -0800, "tubesforall"
wrote:

Nyquist theorem states that a non-variant signal freqency can be reproduced
that is 1/2 the sample rate. Unfortunately, music that is invariant is not
terribly interesting.

wot the fuc does that mean? invariant? like disco? a pure sine wave? do you have
a clue?

Thus, the common wisdom that 44.1KHz sampling can
reproduce 22 KHz music is not true.

yes it is. happens all the time. actually, the spec is for 20khz, the clock was
made a wee bit higher, laddy, as a fudge factor.

A seminal paper from MIT shows that distortion related to sampling must
consider both the sample rate and the target word size. For today's
CDs--that is 16 bits. Thus, according to this paper, a minimum of 8X
frequency is required--10X is better. Working backwards, that means that CD
technology can only reproduce, at best, 5.5 KHz before distortion starts to
enter in.

that may be true... but harmonics above 5khz with .001% distortion are of no
conseguence. please note that all distortion of original digitized material
above 10khz is in-audible by being outside the bandwidrh.

This is independant of the construction of filters and assumes a
boxcar filter (impossible in real life.)

i guess you never swept a motorola 23 pole modem/voice filter...

Other solutions have worked hard to reduce this problem by oversampling,
adding bits, etc. All these solutions smooth the distortion created by the
original system, but they can not add information back in that is lost.

distortion of a signal doesen't lose anything, it only gains. frequency responce
anomalies can lesson some data.

What they can do is create better sounding music by smoothing out the
jaggies in the distortion.


now I guess you're ready to move on to french fry school...