1. Roy Allison
passed away on March 1. The Summer issue of the BASS will be dedicated
to him.
2. For February we joined the AES
as guests to hear Eric Blackmer talk about his thesis that the human
hearing, though limited to 20 kHz on the frequency domain can still
respond in some audible way to frequencies above that. Their mikes are
flat to 40 kHz and have a noise floor of 20 dBA (which is quite remarkable
for small diameter mikes). Some years ago Brad Meyer and David Moran
(of the BAS) did a test of the audibility of a CD quality (i.e. 22 kHz
bandwidth) channel when inserted in to a HiRez playback channel (published
in the AES journal). After 500 or so trials, the listeners responded
no better than chance. Since then their study has often been criticized
for the source material, methodology, and playback system, but no one
has done a study proving otherwise. Their program source was commercial
HiRez recoding, however most if not all were made with microphones having
a cutoff of 20 kHz or so. Earthworks has a library of 40 kHz recordings
so perhaps it is time to revisit the tests. Messrs M & M may be
weary of it all but I'm sure they would be glad to provide technical
assistance to anyone wishing to do another round of testsin particular
the loan of the ABX box which allows easy double blind tests

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