Re: [Harp-L] Bending Stress in reeds (was Manji Reed Quality)

[Arthur Jennings <timeistight@xxxxxxxxx>]

I think Rick is asking about overblows.

If you overblow hole six on a C harp, the blow eed chokes and the draw reed
sounds, but it produces a note (Bb) one semitone higher than it does when
you sound it by drawing. Why is that?

On Wed, Nov 23, 2011 at 12:20 AM, Vern <jevern@xxxxxxx> wrote:

> Unless it is excited by the closing reed in the same chamber, the opening
> reed won't sound at all.  If it is excited by the closing reed, (as by
> bending in a diatonic) during diatonic bending, the pitch is between the
> pitches of the two interacting reeds.
>
> Vern.
>
> On Nov 22, 2011, at 9:36 PM, Rick Dempster wrote:
>
> > What's always escaped me Vern, is why a reed plays a semitone higher
> when it is played with the reverse breath - ie a draw reed played with a
> blow, or vice versa. Any clues?
> > RD
> >
> > >>> Vern <jevern@xxxxxxx> 23/11/2011 16:27 >>>
> >
> > On Nov 22, 2011, at 4:12 AM, Tom Cox wrote:
> >
> > >  ........I dont wail and hammer notes with excessive
> bending.................
> >
> > The assumption that bending puts extra stress on reeds seems ubiquitous
> among harmonica players..
> >
> > Although extra effort on the part of the player is required to establish
> the embouchure resonance to bend the pitch, the analogy that extra stress
> on the player creates extra stress on the reed may not be warranted.
> >
> > The stress in any reed is purely a function of its vibrational
> amplitude.  In bending, it is not obvious that either reed vibrates at a
> greater than normal amplitude.  I think that it is very likely that
> amplitude is greatest when the embouchure resonance is the same as the
> un-bent natural resonant frequency of the reed.
> >
> > I looked again at Dr Bahnson's video on bending.  It shows the reeds as
> bending takes place. Although I didn't see any extreme deflections, the
> pictures were not easy to interpret.
> >
> > Vern
> >
> >
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-- 
Arthur Jennings
http://www.timeistight.com