Re: Beethoven cadenza versions?

[John Hill <jphill@home.com>]

"Megan, Ken and Anne" wrote:

> I don't want to start another humming debate, but since Bengt mentioned
> these CDs ........ from the Technical Notes:
> "Surface noise was reduced using powerful "linear prediction" and "adaptive
> noise cancellation" software developed by Sonic Solutions."

Sonic Solutions is a DAW (digital audio workstation) used for editing and
mastering of material for CD release.  The fact that they reduced "surface
noise"
suggests that they were working from a vinyl disc (or acetate) as the analog
master
format before converting to digital.  These noise reduction algorithms are very

powerful and can substantially lower the noise floor of older master formats
like analog tape (without noise reduction) or other older formats.   They can
also
assist with newer recordings by removing what we call "room tone", which is
the noise signature of a room picked up when working in large auditoria or
churches.  This is quite useful in lowering the noise floor of an acoustic
recording, particularly "classical" music, which tends to have very quiet
sections
and lots of dynamic range.

These algorithms do not, however, do anything by way of removing humming.
You normally feed in a sample of one second's worth of the noise you wish to
remove and this sample needs to be a fairly "steady-state" noise.  Since
humming
tends to be extremely time- and frequency-variant, the algorithm would have
a pretty hard time discriminating it from other artifacts within the music or
the
music itself.

But hey, I'd leave it in even if I *could* take it out.

cheers,
jh