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High-frequency hearing in humans
Deall All,
In connection with this thread, I suggest taking a look at:
Ashihara, K. and Kiryu, S. (2000).
Influence of expanded frequency band of signals on non-linear
characteristics of loudspeakers, J. Acoust. Soc. Jap. (J)
56, 549-555.
Ashihara, K. and Kiryu, S. (2003). Audibility of components above 22 kHz
in a complex tone, Acustica - acta acustica 89,
540-546.
Brian Moore
Just to show that it is not a
simple question of loudspeaker quality but also of recording quality I
send you a Matlab script producing one square wave "sampled" at
48000 and another at 192000 Hz. The difference is audible through
any loudspeaker.
clear all
sf1 = 48000;
sf2 = 192000;
dt1 = 1/sf1;
dt2 = 1/sf2;
du = 1;
f0 = 5000;
t1 = 0:dt1:du;
t2 = 0:dt2:du;
s1 = square(2*pi*f0*t1);
s2 = square(2*pi*f0*t2);
sound(s1, sf1)
wavwrite(s1, sf1, 's48000')
pause(1)
sound(s2, sf2)
wavwrite(s2, sf2, 's192000')
Best,
Dik
> -----Original Message-----
> From: AUDITORY - Research in Auditory Perception
>
[
mailto:AUDITORY@xxxxxxxxxxxxxxx] On Behalf Of Joachim Thiemann
> Sent: vrijdag 4 februari 2011 15:37
> To: AUDITORY@xxxxxxxxxxxxxxx
> Subject: Re: [AUDITORY] High-frequency hearing in humans
>
> On Thu, Feb 3, 2011 at 23:08, Kevin Austin
<kevin.austin@xxxxxxxxxxxx>
> wrote:
> > A colleague of mine has been working on clicks in an
electroacoustics
> aural perception course. He discovered that a 48kHz sampling rate
was
> "too crude", and that working at 96kHz (or higher), the
differences
> between clicks over 8kHz were noticeable. This is not quite
what
> sampling theory seems to say. At 44.1kHz, a single sample click
> represents 22kHz, and a two sample click represents 11kHz. How does
one
> represent a 16kHz click with a 44.1kHz sampling rate?
>
> I think one has to be careful about the actual D/A hardware in
these
> cases. Oversampled sigma/delta? R-2R? What are the
postfilter
> characteristics? I think with these type of stimuli,
differences
> might be audible: even if the same soundcard is used at
different
> rates, the filter should change. The differences in
filter
> characteristics might extend to lower frequencies, where they might
be
> picked up by individuals with good hearing.
>
> Joe.
>
> --
> Joachim Thiemann ::
http://www.tsp.ece.mcgill.ca/~jthiem
Brian C. J. Moore, Ph.D, FMedSci, FRS,
Professor of Auditory Perception,
Department of Experimental Psychology,
University of Cambridge,
Downing Street,
Cambridge CB2 3EB,
UK
Tel. +44 (0) 1223 333574
Fax. +44 (0) 1223 333564