1. From John Atkinson in reply to a
letter in the November 2014 Stereophile:
"By the time this issue hits newstands...the Meyer-Moran article
to which you refer. [Audibility of a CD-Standard A/D/A Loop Inserted
into High Resolution Playback] ...will have been shown to be incorrect
in a paper presented at the 137th AES convention [by Robert Stuart of
Meridian].
I forwarded this to the people involved and in the
resulting discussion Robert Adams of Analog Devices pointed out the
the filters used in the testing were much sharper than those used in
typical pro audio convertors. In fact the total impulse response length
of their (Stuart's) digital filter is in the range of 8ms. A typical
converter filter is in the range of .5ms to 1ms. So this is overstated
by a factor of at least 8.
Why Stuart did this is not clear, perhaps to generate
an audible result for the purpose of the paper. And his company (Meridian)
is in the business of marketing high resolution audio equipment. However
it's meaningless for real world results. Unfortunately this paper has
caused some mischief in the audiophile community since it is being used
by proponents of high resolution audio to justify their cause (High
Resolution Audio: Does it Matter? Amir Majidimehr, Wide Screen
Review, January 2015).
2. BASS V36N4 has been published. It
features meeting summaries of Charles P. Repka: Engineering, Recording
and the Videodisc by David Hadaway, and Tom Perazella: Unlock the Music
by Alvin Foster. Also West Side Story at Symphony Hall by John S. Allen
and Audio Exp North America by Jim Buchanan and reports on CEDIA Expo
2014.

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