----- Original Message -----
From: "Dave Bradley" <db65@xxxxxxxxxxx>
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, and with good
reason,
the vinyl that the stylus is being dragged through can't reproduce up
there
either. There may be harmonics up there, but analog isn't delivering it.
So
if the problem is that digital isn't giving you something which you can't
hear, but can sense, keep in mind that analog isn't giving that to you
either.
The fact of the matter is that a pure sinewave, when digitized properly,
and then played back through a proper DAC will give you that same pure
sinewave again. It doesn't give you stepped response. It doesn't give you
a
triangle or square wave. It gives you that pure sinewave. Just because
zooming in on the waveform in your favorite DAW software shows you
individual sample values and a less than smooth wave form doesn't mean
that
the playback will be that way. Keep in mind that in the end, what you are
hearing is analog generated from a set of digital instructions or
samples. You are still hearing analog.
Presumably, until we perfect the digital transducer (and the digitized
human brain as well) we will be hearing analog, regardless of the
nature of the sound source. Even if you could use fast-acting servomotors
to respond in a digital fashion to a digital signal, our eardrums and
sensory nerves would be analog!
This makes the actual vital question whether the analog signal recerated
from the digitized input is discernibly different...TO THE HEARER...from
the original analog signal fed into an analog transducer. To answer this,
you would need two identical speakers fed by two identical amplifiers, one
fed a digital signal and the other fed an analog signal at the EXACT same
level.
I suspect there would be no difference...IF the hearer was not informed
as to which source was which. I also suspect this test isn't possible,
since most commercial CD contents are remixed by "experts" who are trying
to create a saleable...not necessarily an accurate...version of the
source signal!
Steven C. Barr