It wasn't a scientific experiment--just an engineer having a bit of
fun--though he seems to have had a point to make, if not a detailedl
hypothesis to test. I just thought the structure was interesting, and
worth considering if our goal is to develop a listening test or tests.
Perhaps the thing that I find most interesting here is that it involved
a real-time, uninterrupted listening experience of A, B, C, and D.
Perhaps the brain does respond differently to such a listening
experience.
Matthew Barton
MBRS
The Library of Congress
101 Independence Ave., SE
Washington, DC 20540-4696
202-707-5508
email: mbarton@xxxxxxx
Marcos Sueiro Bal <mls2137@xxxxxxxxxxxx> 1/28/2008 10:40:58 AM >>>
Matt,
This is an interesting link, but as a scientific experiment it does not
seem very useful: What is the hypothesis? How are we quantifying it? A
statement such as "my fellow listeners appeared to be equally
uncomfortable" does not seem conducive to analysis.
If the highs were perceived not to be "as silky smooth" --in other
words, if the differentiating factor has been identified after just one
listen of a short passage--, should not the same listener be able to
correctly identify such a difference in a blind test? Logic seems to
indicate that he should, but perhaps the brain works in mysterious
ways.
Incidentally, it seems that not all ABX tests have concluded that
listeners are less sensitive than we thought. I was told in school that
most average Joes can hear at most a difference of 1 dB, but a group of
5 listeners in an ABX test perceived differences of 0.4 dB 93% of the
time (note: this is not a peer-reviewed paper, and this is from the ABX
web page, so it is not conclusive evidence).
http://www.provide.net/~djcarlst/abx_lvl.htm
Cheers,
marcos
Matthew Barton wrote:
Here's a link to an article from the October issue of Stereophile,
in
which an interesting approach to blindfold testing is described:
http://www.stereophile.com/asweseeit/1007awsi/index.html
This is not an analog vs. digital article, and I'm not endorsing the
test or or its results, or any conclusions in the article, but I
think
the approach is interesting. Instead of an A:B comparision, in which
listeners first heard A, and then B, and were asked for opinions,
this
engineer created a composite patchwork of different formats using a
repetitive passage from a recent recording of Handel's Messiah. He
didn't tell his audience that this is what they would be hearing:
"It turned out that we'd been unwittingly involved in a blind
listening
test. The DVD-A was a ringer. Philip had chosen a Handel chorus in
which
the same music is heard four times. He had prepared four versions of
the
chorus—the original 24-bit/88.2kHz data transcoded straight from
the
DSD master; a version sample-rate–converted and decimated to
16/44.1
CD data; an MP3 version at 320kbps; and, finally, an MP3 version at
192kbps—and spliced them together in that order. The last three
versions had been subsequently upsampled back to 24/88.2 so that the
DAC's performance would not be a variable. The peak and average
levels
were the same for all four versions; the only difference we would
hear
would be the reductions in bandwidth and resolution. "-- from
"Watching
the Detectives," by John Atkinson, Stereophile, October, 2007.
We can all argue about the specs here, but the most interesting
thing
to me is that the changes in the audio unfolded over four iterations
of
the same passage of music in the same recording. Listeners were not
asked to use their memory of recording A to appraise recording B,or
vice
versa. They heard (or did not hear) the changes as part of
continuous
listening experience.
Matthew Barton
MBRS
The Library of Congress
101 Independence Ave., SE
Washington, DC 20540-4696
202-707-5508
email: mbarton@xxxxxxx