Re: [ARSCLIST] Sampling Theory (was Fred Layn's post on the Studer list re: Quantegy)

[Mike Richter <mrichter@xxxxxxx>]

At 03:03 PM 1/17/2005 -0500, Dave Bradley wrote:
> I find it interesting that people point to subjective studies about what
> can be sensed above 20 KHz, or above 15 KHz for that matter, and say that
> because digital doesn't go there it's inferior. Take note that the
> cartridge on your turntable isn't going there either

But it is. That is, the falloff from uniform reproduction may be steep when
given sine waves, but waveshape is still approximated. The Nyquist limit is
abrupt - above it are only artifacts - and it is made more so by preceding
circuitry if the engineer is competent. Square waves at two-thirds the
'maximum' frequency are far from square, but they do have the right
components, the lower harmonics are not terribly out of phase and overall
they approximate the input waveform at least grossly where the sampled
signal does not.

I've had people make the same argument on tape until I showed them that I
could read the bias frequency from the tape on a Tandberg - a signal an
octave above the supposed limit of response. I'm sure the Studer will do
the same. It was many db down, but still easily isolated from the noise and
easily measured.


Mike
--
mrichter@xxxxxxx
http://www.mrichter.com/