Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: [Phys-l] [tap-l] more on sound



Interesting web site.

I have a related question. Why do some stereo systems (with digital
displays) show negative decibel readings? This seems to contradict the
fact that the threshold of hearing is defined as 0 dB.

tap-l@lists.ncsu.edu writes:
Greetings,

I went into google and put in decibel. I got the following that tells
one more than I would want to know. In it was said, "One decibel is
close to the Just Noticeable Difference (JND) for sound level." I
wonder if this is the cause.

http://www.phys.unsw.edu.au/~jw/dB.html

Try this for the violin found on the same website

http://www.phys.unsw.edu.au/~jw/violinarticulation.html

Hope this helps.

Dick


Helping teachers who facilitate, motivating students who learn.
Dick Heckathorn 14665 Pawnee Trail Middleburg Hts, OH 44130
440-826-0834
www.cvcaroyals.org/~rheckathorn
Physics is learning how to communicate with ones environment so that
it will talk back.


-----Original Message-----
From: tap-l-owner@lists.ncsu.edu [mailto:tap-l-owner@lists.ncsu.edu]
On Behalf Of Anthony Lapinski
Sent: Tuesday, April 25, 2006 7:28 AM
To: tap-l@lists.ncsu.edu; tap-l@lists.ncsu.edu;
phys-l@carnot.physics.buffalo.edu
Subject: [tap-l] more on sound

These questions were recently asked by students of mine:

1. For sound intensity level, why is the decibel unit is used instead
of
the bel (1 dB = 0.1 bel)?

2. Do the "f holes" in violin sound boards play any role in the
quality of
the sound produced? Do these openings somehow "compliment" the shape
of
the resonant cavity? Acoustic guitar sound boards are "figure 8"
shaped,
yet the openings are circular.

3. In a choir, why are the higher-frequency notes often easiest heard?
It
could be because they sing louder. Or is it because our ears, being
closed
pipes, are most sensitive around 3000 Hz?

Any comments/insights on these questions?

===== TAP-L Mailing List =====
To modify your subscription status, visit
http://lists.ncsu.edu/cgi-bin/mj_wwwusr and select 'Sign-In'. If you
do not have your password, you can enter the email address you are
subscribed with and have the password emailed to you. If you have any
questions, please contact the list moderator, keith_warren@ncsu.edu




===== TAP-L Mailing List =====
To modify your subscription status, visit
http://lists.ncsu.edu/cgi-bin/mj_wwwusr and select 'Sign-In'. If you do
not have your password, you can enter the email address you are
subscribed with and have the password emailed to you. If you have any
questions, please contact the list moderator, keith_warren@ncsu.edu