[Audio Empire]

On Tue, 29 Mar 2011 06:50:05 -0700, Arny Krueger wrote
(in article ):

"Andrew Barss" wrote in message

Arny Krueger wrote:

The well-known problem with laser pickups is that they
do not deform the groove in a way that is complementary
with the way the groove was deformed when the LP was
cut. There is also no "plowing action" that pushes fine
particulates out of the way. Therefore ,nonlinear
distortion can be higher and groove noise can be
oppressive.


Interesting point. A couple of years ago I heard an NPR
interview with a couple ofphysicists who were using wither lasers or
scanning electron microscopes to pick up the sound in wax
cylinders deemed too fragile to play conventionally.
I was excited to hear this, then not impressed -- the new
tech played slightly better, but it was still pretty
awful.

I am aware of this. I applaud means for recovering sound that minimize the
impact on rare source material.

I suspect that the recovered recordings were technically deficient due to
the many serious problems with the recording and production environment of
the day.

I wonder if the same deforming and
cleaning effect occurs with whatever was used to play wax
cylinders as designed (and if they would sound better if
played that way than with the new-tech
system).

I suspect that it may be possible to model the deformation process from the
recovered wave and apply appropriate corrections in the digital domain.



Yeah, that could work, as long as somebody could figure a way to model it
accurately. The same with the sound. The acoustic recording process was
fraught with compromise. The diaphragms that moved the cutting needle were
grossly inefficient, it took a lot of acoustical power to cut a groove. The
system had worse than contemporary telephone quality (believe me that was
bad) and the recording medium was inherently extremely noisy. Algorithms have
been developed for the Library of Congress to correct some of these problems,
but not all of them. I've heard some Caruso transcriptions that actually
sound halfway decent. It turns out that much wider frequency range than one
can actually hear when playing back these recordings is actually THERE, but
it's so attenuated that you can't hear it. These can be boosted back to
audibility while digitally reducing out-of-band noise. They'll never be
Hi-Fi, I suspect, but as the technology improves, I'm sure that many of these
old recordings will yield more and more of the sound that's actually there.