RE: Coffee cup

["MLeFree" <mlefree@xxxxxxxxxxxxxxxxxxxxxx>]

Scorcher wrote:
> I was taking a lesson the other day and my teacher showed me the
> "Coffee Cup Mute" thing. WOW, what a cool effect!
>
> He explained that the size/shape/proportion seems to be pretty specific to
> the harmonica one is playing - for instance, he was playing a CX-12 in
> C-Tenor, and the cup he was using only REALLY "worked" on about holes 2-8,
> but not in the top octave (at least not as profoundly). When he hit the
> "sweet spot" where the effect was strongest, it was MUCH more
> dramatic than any hand resonance I've heard.
>
> Do any of you have any experience with this effect? (I've already gone
> through every cup in my cupboard trying to find one that works!) So, does
> anyone have a favorite cup?  ;-) Or,at least a favorite harmonica to use
> with a cup?

Then a number of folks contributed their interesting experiences and
comments.

I was just waiting for Pat Missin to jump on this one with both feet,
thinking OK, I know he and Douglas Tate have both written about this'n.  He
did jump on it, but his answer took me off-guard.  I was expecting Pat to
explain that Scorcher's coffee cup is a fine example of a Helmholtz
Resonator.  But, he didn't, so I will.  :)

When you form a suitably-sized chamber near or around your harmonica (or
other sound source) with a coffee cup or your hands it becomes, yes, a
Helmholtz Resonator.  The shape and size of the resonator are what determine
its natural resonant frequency.  This means that certain frequencies
dictated by the shape and size of the chamber are prefentially amplified
relative to the others.  This accounts for why certain cups work better with
certain keys of harps.

In a closely related technique, Douglas uses a special hand cupping method
to "play loud softly", as he calls it.  In his book, "Play The Harmonica
Well", he describes how to tune your hand cup to the note you are playing to
achieve this amplifying resonance.  The method allows him to play without
amplification alongside an orchestra.  I've used the technique myself and
the effect is profound.

On Pat's terrific site he describes the hand resonance technique fully,
complete with sound samples, and cites references for Helmholtz Resonators.
If you have "the least interest at all" (as Pat might say) in this
phenomenon, you really should take a look at this page on his site (even
before he finishes his article on coffee cup resonators) and follow the link
to the Helmholtz Resonator page:

http://www.patmissin.com/uncommon/uncommon06.html.

Cool thread, Scorcher (again...  :)!

Michelle