[Harp-L] Re: Waxing Rivets for Overbends [plus!]

[Bobbie Giordano <bobg@xxxxxxx>]

I finally relocated that link to the image I sent yesterday, BTW... It's
provided by the Institute of Computational Fluid Dynamics in Tokyo, Japan.

Here's the URL:  http://www2.icfd.co.jp/examples/karman/kr2.htm

For another link, go here to see the mpeg movie which I couldn't manage to
add to my small weblink... Storm hit my server, I think.  [I really should
get packing for SPAH anyway!]  ;)

Additionally, though, here is the website's explanation of their movie image:
>The periodic nature of the Von Karman vortex street is best 
>illustrated in the third example, which shows the vortex street 
>created by a flat plate.  This movie only includes a single cycle 
>of the phenomenon, therefore for best viewing, configure your 
>MPEG viewer to play the movie in a continuous loop.

[For example in WinAmp, click Toggle Repeat to loop the short movie.]

Obviously, if one is considering the effects of a harmonica reed, the idea of
using a "flat plate" seems more useful than a cylinder.

As for why TurboTape works?  Well, it doesn't entirely, but it does help
considerably.  It seems to me it's the tiny added raised edge surfaces on the
downstream side of the reed which disrupt the natural inclination of the air
stream to take on a spiral flow and set up the Karman vortex street action,
and thereby also disturbs the ability of resonance with the reed's natural
resonance frequencies to occur, causing that obnoxious ring.  But, for me,
therein lies the other problem some find with using the TurboTape solution.

Interference with the reed's natural resonance frequencies, of which, BTW,
there are many, perhaps nearly infinite, does seem to occur using TurboTape.
This is because each reed is not uniform in shape, being tapered and having
various profile abnormalities from the simple rectangular slab we may all
imagine it to be.  For another, every tuning ditch or scratch on the reed
affects this whole profile as well, making each reed singularly unique in its
ability to perform.  [Can I hear an 'amen' to THAT!!!] :)

Thus, as some report, [myself included,] the tonal qualities of reeds with
this tape solution affixed are somewhat dampened.  It does indeed settle the
reed's torsional motion inclinations, which I suspect are caused as well as
intensified by the Karman Street air flow situation, both or either of which
may contribute to reed squealing.  But, resonance qualities are also dampened
for the reed in all its capacities.

The reed still plays, but it doesn't "dance", so to speak.  It's more stable,
but lacks "life".  That's about all I can think of to describe it at the
moment.  But, I'm reminded of a recent experience with another instrument...

Recently, I ventured into buying a penny whistle or two.  I did some modest
research and decided to buy two, both in D.  One is a classic, often chosen
whistle by many beginners.  The other is slightly more pricey and maybe a
"step up" from the other.  I found there is a WORLD of difference between
them and the way I noticed it went like this...

I am NOT a flute or whistle player, BTW!  I first tried out the lesser priced
instrument, and it seemed easy enough.  I then tried the other one and found
it, yes, more difficult... more "sensitive" is the word I'd use.  But, I
continued to experiment with the "better" instrument and began to find some
comfort level.  Then, I returned to the first instrument and discovered two
things... it was easier than before [practice effects, I guessed,] but, which
surprised me, it was somehow more limited in range and capabilities.  It was
then I also noticed a distinct tonal difference as well... less fullness,
nuance, subtlety, dynamic range, ease of production and movement from tonal
aspect to the next.  [Remember, I am NO pro musician! ;)]  Going back to the
costlier penny whistle, I was immediately aware of the difference and
capacity this instrument had over the other.  Mainly...?  Subtle response and
control.  Unrecognizable on an instrument of less quality, but eye-opening
once you are "able" to recognize it!

I guess what I'm trying to convey is that having an easy instrument to play
is great if you want to learn how to easily make music.  But, if making music
becomes your goal, even an easy instrument begins to get more complex.  And,
eventually, every tiny detail can take on new relevance in allowing you the
expression you desire.

My wax fix was good.  Pat's nail polish fix was good.  Jim's turbotape is
good, too.  But... something's not yet right.  "No fix needed" should be the
real "fix".  In the meantime, folks... choose your poison, hang in there, and
keep on harpin'!!  Here's to the cure...

One pleasant antedote is a SPAH convention!  :)
See you there,

Bobbie
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