Bob wrote,
Cover the hole with a piece of cardboard. The resonance is gone (as even
Michael notes in an earlier post
Bob, Please be more specific in your science. What is it your talking
about when you say resonance? Is it perhaps air space resonance coupling
with the plates? or what. For a physics professor you sure know how to
dance across the room. I'm am glad to see your not using the beer bottles
anymore though, that's a step in the right direction.
I suggested people try the same experiment.
And, whats up with all the name calling, my friend.
Michael Thames
Luthier
www.ThamesClassicalGuitars.com
Site design by Natalina Calia-Thames
----- Original Message -----
From: "BobClair or EkkoJennings" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Cc: "Michael Thames" <[EMAIL PROTECTED]>
Sent: Thursday, December 18, 2003 9:04 AM
Subject: Porcine Vocal Arts
>
> Something about this thread has been nagging me, but I couldn't put my
finger on it until Michael's most recent posts. It reminds me of a t-shirt I
once saw and whch I greatly admired. The t-shirt said:
>
> "NEVER TRY AND TEACH A PIG TO SING.
> IT WASTES YOUR TIME AND IT ANNOYS
> THE PIG".
>
>
> > I said that if you increase the soundhole opening you lower the
resonate
> > air space frequency. You know and I know this is correct, as applied
to the
> > guitar or lute.
>
> Please avoid ascribing belief in your delusions to me.
>
> As I mentioned before, science proceeds by experiment and by publishing
the results of the experiment and the details of how it was performed so
that others may verify your findings.
>
> I have performed the following experiment:
>
> Take a guitar and damp the strings with your hand.
> Hold the guitar up near your face (soundboard towards you) and sing down a
scale.
> At some point you will get a big response (the "Caruso in the stall
shower" effect).
>
> For a typical sized classical guitar this will be in the neighborhood of
the low A on the
> 5th string. (The ladies trying this may need to enlist the help of a male
friend. This is biology not
> sexism. Sorry. Please don't flame me.)
>
> Cover the hole with a piece of cardboard. The resonance is gone (as even
Michael notes in an earlier post).
>
> Now remove the cardboard to open the hole. Sing the original pitch and
while singing that note slowly begin
> sliding the cardboard over the hole until the response just dissappears.
(This will probably happen when you have
> 1/3 to 1/2 the hole covered.) With this new smaller size opening, try to
find the pitch of the resonance. Try higher,
> try lower. You will probably find the resonance about a half step or whole
step below the original pitch.
> Remove the carboard again ( making the hole larger ). Note that the
resonance at the lower pitch is gone.
> Verify that it has re-appeared at the original higher pitch.
>
>
> Again I ask the readers to help Michael out by performing the experiment
and reporting their results.
>
> This works with a lute as well, the resonance on my 10 course is around
the 5th string, C at A415.
>
> As an experiment this has a number of admirable virtues:
>
> 1) It doesn't involve beverage containers.
>
> 2) It is repeatable with consistent results.
>
> 3) It gets right to the point and doesn't involve discussions of
mode-coupling. The resonance involved, whatever you call it, is THE
resonance controlled the open area of the hole, as you have just
demonstrated.
>
> 4) It shows that I am correct. :-)
>
>
> I am amazed at Mr. Thames' persistence in the face of the entire body of
acoustical literature and experiments (both serious lab physics and easily
performed home experiments). This leads to an interesting question:
Michael - do you really believe your own nonsense or is this a form of
recreation for you? You know - kick back after a hard day's work, have a
drink, go to the computer try and yank a few people's chains? If it is the
former I might suggest that you check and see that your spray booth is
properly vented.
>
>
> ......Bob
>
>
>
>
> ____________________________________________________________
> ____________________________________________________________
>
> Replies: (remove the "ZZZZ")
>
> Ekko Jennings: [EMAIL PROTECTED]
> Bob Clair: [EMAIL PROTECTED]
