[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: Rationale for Critical Bands
The point of the books link is that there are
easy online resources for information about the
level dependence of critcal bands, or critical
bandwidth. Here's a better one, perhaps:
http://www.google.com/search?hl=en&tbs=bks:1&q=%22critical+bandwidth%22+%22level+dependence%22
Maybe the search gives different results in
different locales? I see the first hit as a link
to a paper titled "LEVEL DEPENDENCE OF CRITICAL
BANDWIDTH". And here's one that's found in both
searches, which backs up my statement that "some
methods show a level dependence of the measured
critical bandwidth":
http://books.google.com/books?id=TDPIO01DLSUC&pg=PA236&dq=%22critical+bandwidth%22+%22level+dependence%22&hl=en&ei=8HoWTKjkGIOOMtCv5ZkL&sa=X#v=onepage&q=%22critical%20bandwidth%22%20%22level%20dependence%22&f=false
(in case it doesn't work where you are, it's p.
236 in Handbook of Signal Processing in Acoustics
by David Havelock, Sonoko Kuwano, Michael
Vorländer).
On the level dependence of auditory filters,
there are many papers by Patterson, Glasberg and
Moore, Rosen and Baker, and many others, that
explore auditory filter level dependence within
the paradigm of detection of tones in noise
maskers. Here's one by Pick, 1980:
http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JASMAN000068000004001085000001&idtype=cvips&gifs=yes&ref=no
and Rosen, Baker, and Darling 1998:
http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JASMAN000103000005002539000001&idtype=cvips&gifs=yes&ref=no
which starts the abstract with "Auditory filters
broaden with increasing level".
and this one by Glasberg and Moore 2000
specifically talks about the derived
psychophysical filters resembling filtering at
the basilar membrane, including the level
dependence:
http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JASMAN000108000005002318000001&idtype=cvips&gifs=yes&ref=no
What I'm not familiar with is the alternate
conclusion, that there is a level-independent
critical bandwidth. Thanks for the links you
sent, some of which do seem to be about that, or
assume that. I'm open to the idea that in
brainstem, there is less level dependence, or
that some kinds of psychophysical experiments
give a CB that doesn't vary with level, though I
haven't really seen the evidence for it yet.
Maybe you can point us toward some.
Dick
Richard F. Lyon wrote:
The "critical bandwidth" is a simplification of
the concept of a psychophysical "auditory
filter", which is a bandpass filter that can be
measured with various experiments, such as
detection of probe tones in notch-noise maskers.
There is no difference between the concepts of
the "auditory filter" and the "critical
bandwidth", let alone in simplicity. Both are
extremely oversimplified and loose, and thus
have been causing unending confusion.
The concept is a psychological one, and whenever
it was not verified by physiological data it has
turned out to be pretty much worthless.
Find more in books:
http://www.google.com/search?q=%22critical+band%22+%22level+dependence%22&tbs=bks:1
Sorry, this is not a useful link. Or does it
mean to put off people from finding something?
If there is support for your claims in the
literature, please say where. Thank you.
Martin
---------------------------------------------------------------------
Martin Braun
Neuroscience of Music
S-671 95 Klässbol
Sweden
email: nombraun@xxxxxxxxx
web site: http://www.neuroscience-of-music.se/index.htm
----- Original Message ----- From: "Richard F. Lyon" <DickLyon@xxxxxxx>
To: <AUDITORY@xxxxxxxxxxxxxxx>
Sent: Monday, June 14, 2010 5:42 PM
Subject: Re: Rationale for Critical Bands
The "critical bandwidth" is a simplification of
the concept of a psychophysical "auditory
filter", which is a bandpass filter that can be
measured with various experiments, such as
detection of probe tones in notch-noise
maskers. These measurements can be done at
different levels, and show a clear
level-dependence of the psychophysical auditory
filter and its bandwidth, or critical band,
following a pattern consistent with the
variation seen in cochlear mechanics.
Some types of experiments reveal a level
dependence in the CB, presumably based directly
on the cochlear filtering. Other experiments
show a more level-independent CB, and that's
what corresponds to the further processing in
IC, according to some experimenters.
Find more in books:
http://www.google.com/search?q=%22critical+band%22+%22level+dependence%22&tbs=bks:1
Dick