Re: Ultrasonic Hearing in Music Recording & Reproduction

[lazzaro <lazzaro@xxxxxxxxxxxxxxxxx>]

Hi everyone,

	In the pro audio world, engineers who
audition 48K vs 96K often like the way 96K
sounds.  But whether this has anything
to do with hearing ultrasonics is another
matter entirely. For example, the same
D/A converters, clocked at 96K & 48K, may
have fewer sonic problems with clock jitter at 96K.
This phenomena might be producing the
sonic changes studio engineers report.

	Conversion hardware is not ideal ... apart
from clock jitter, there are other non-idealities
that may sound different in the < 20K regime
for 48K vs 96K that may be the root cause.

        To get a sense of what pros are hearing,
consider this review of the Pro Tools HD system
(very popular in studios today, although many people
take the digital outs from Pro Tools and run them
through better converters than the ones Digi
offers).  The review is by Sound on Sound's
level-headed Hugh Robjohns. His description
of the difference between listening to 96K
recordings at 48K and 96K playback rates,
using Genelec 1031s for monitoring:

The acoustic instruments (violins, violas and guitars
mainly) became significantly more 'real'. The system
conveyed much more information about the wood of
the instruments, their size, movement and relative
spatial positioning -- it was as if an acoustic veil had
been removed. I know this is starting to read like a hi-fi
magazine, but the difference really was that obvious.
Whether Joe Bloggs would notice the improvements
in your recordings on the £99 ghettoblaster he bought
in Currycomets at Christmas is another matter entirely...

	This was excerpted from:

http://www.soundonsound.com/sos/May02/articles/protoolshd.asp

---
John Lazzaro
http://www.cs.berkeley.edu/~lazzaro
lazzaro [at] cs [dot] berkeley [dot] edu
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