I wrote, about a passage in Stevens' book _Sound and Hearing_
> >
> > > BTW, it seems to have a misprint as well, because it says that
> > > these are under ideal conditions, and than "actually, few human
> > > adults can ordinarily hear tones much above 8,000 cycles". I'm
> > > sure they meant 18,000.
> > >
> >
Ken Steele replied:
> > This may not be a misprint but a reference to equal loudness contours.
> > Our sensitivity to sounds is a U-shaped function of frequency.
>
> I should have said loudness contours and masking effects. Note MP3
> encoders take advantage of these effects in their "lossy" compression
> technique by selectively removing frequencies from the file.
>
While not disputing the phenomena cited by Ken, I'm still
surprised that "ordinarily" the cut-off is as low as 8,000 Hz. Of
course, it all depends on what is meant by "ordinarily". I'd
suggest an operational definition would be a test while watching
TV at normal volume. Would a subject notice a tone inserted
during the programme at the same volume but above 8,000 Hz?
Data, Ken?
-Stephen
------------------------------------------------------------------------
Stephen Black, Ph.D. tel: (819) 822-9600 ext 2470
Department of Psychology fax: (819) 822-9661
Bishop's University e-mail: [EMAIL PROTECTED]
Lennoxville, QC
J1M 1Z7
Canada Department web page at http://www.ubishops.ca/ccc/div/soc/psy
Check out TIPS listserv for teachers of psychology at:
http://www.frostburg.edu/dept/psyc/southerly/tips/
------------------------------------------------------------------------
