[Harp-L] XB-40 Squeals

[Bobbie Giordano <bobg@xxxxxxxxx>]

[Hope this doesn't duplicate... I got disconnected first time I sent it.]

Recently, among other beneficial hints and suggestions, [as usual,] Winslow
Yerxa wrote:
>--- In harp-l-archives@xxxxxxxxxxxxxxx, Paul Bowering 
><paul_bowering@xxxx> wrote:
>> One problem I definitely want to address is the squeal
>> I get on some higher draw bends. Is this to be
>> rectified with the beeswax/nail polish fix. Which reed
>> should it be applied to; the 'normal' reed or the
>> auxilliary? Anyone ever micropore one of these?
>
>The wax (or nail polish) fix might work if the squeal has the same 
>cause as the Lee Oskar squeal. I can make an Oskar squeal without 
>even trying to bend the note, but I have not had that experience with 
>the XB-40. YMMV, but this suggests to me that they do not share the 
>same problem.

Having spent [probably too much] time studying such reed action phenomena, I
too can cause the squeal to sound on just about any harmonica, even a Renny!!
;)  I also have an "A" XB-40, and I can make this squeal on the upper notes
as well.  So, I have to disagree, therefore, that this "noise" problem does
not seem related to what can be sounded on an XB-40, as the sound is very
much like the same ringing you can produce on other harmonicas.

>Does the squeal occur when you are not bending a note? If so, then 
>the wax fix would be most likely be applied to the regular reed that 
>sounds and not the auxiliary reed.

This annoying ringing sound can be produced with or without bending notes,
and yes, and the wax fix, nailpolish fix or turbotape fix would all possibly
be useful to minimize the problem.  What Winslow suggests is definitely true,
though, that you attempt a cure on the regular reed in question.  This is
because, as I've found, it is always the closing reed which squeals.  So, if
you get this ringing sound on a draw reed, it's the draw reed that's whining;
if a blow note, it's the blow reed.  If you're bending a note, in which the
opposing reed in the chamber is also activated, and you hear the squeal, it's
still the reed of the note you're bending.  For example, it's the draw reed
in a draw bent note that's acting up.

Turbotape stabilizes the reed to diminish its aberrant behavior, but some
don't like how it seems to also mute the sound a little.  The effect of the
wax fix or the nail polish fix is due to the location of these substances
where they are applied; that is, near the root of the reed where it meets the
rivet pad.  From some observations I've made, it does seem the reed gets an
unstable torsional motion going, but the emanating point of the disturbance
that causes the squeal appears to come from the root area of the reed more
than the tip area that exhibits the torsional movement.  It seems torsional,
BTW, because the tip of the reed can be seen to dip down into the slot more
at one corner of the reed tip than the other, meaning the reed is being
slightly twisted.

 You could take the harp apart, 
>tape off the auxiliary reed so that no air can pass through it, then 
>try the note. If the squeal condition changes, then you know that the 
>auxiliary reed is involved somehow, but that still doesn't mean that 
>it's the one squealing, only that its presence in the airstream has 
>some part in creating the condition for the squeal to happen.

The presence of the auxiliary reeds in XB-40s, as with the presence of
opposing reeds in regular diatonics, play a part in how the instrument
sounds, but they don't really matter, IMO, where this squealing noise is
concerned, because even chromatics with their isolated reeds [due to valving
with windsavers] can exhibit this irritating ring, even to not hearing the
reed's normal note at all!  It really does seem to be wholly dependent on
properties of the reed that's squealing... even if produced on a reedplate
unattached to anything else.  But it is only in closing reed mode; at least I
can't cause it to happen in opening mode.  I just get the overbend instead!

The only other thing I can think about this, since I don't believe the other
reed plays much of a part here, is that, however, the reedslot may indeed be
instrumental in some way [by its shape, narrowness of side gaps, distance
from the reed's riveting, or some other factor] that influences the
production of the squeal, and therefore, also why some harmonicas seem more
prone to its occurrence than others.

More than 2 cents, I know! ;)
Need to get packing again now for SPAH... see y'all on the flipside!  [Or in
St. Louis!!!] :)))

Cheers!
Bobbie

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