Tuned Metal Bodies

[Winslow Yerxa <76450.3230@xxxxxxxxxxxxxx>]

TO: internet:harp-l@xxxxxxxxxxxxxx

Somehow I missed the beginning of this thread, and have now gone
back and captured it.

I'm still not convinced that a harp that pings when you strike it
is tuned to a particular frequency that has any special relation
to the notes of a harp.

You've probably tried playing a harp into a cup or glass, right?
It gets louder and fuller-sounding. Likewise, if you play it
through an old gramphone horn like Will Scarlett sometimes does,
you can make it amazingly loud.

While the horn, which is made of pressed paper fibers, won't ping,
a jar or glass will. There may in fact be an easily identified
resonant frequency in that ping. And yet the jar or glass (or
pingless paper horn) will still amplify frequencies other than its
resonant frequency.

Has Hugh mentioned what metal Norman's harps are made of?
Could it simply be harder than the soft and thunky aliuminum used
for Meisterklasse instruments? As he points out from his
particular experience in tuning orchestras, some materials
resonate better than others even when the resonance is forced.
This can be due to materials and shape as much as to any inherent
tuning in the object.

I'm not saying that resonant frequency can't or won't play into
this. But I'm skeptical that it does. Hardness of material and
general resonance due to shape - like that of the curved, large,
hard surface of the plate in my tuning fork analogy, seem more
likely culprits and, in fact, are more likely to be useful.

After all, a tuned body will create "wolf" notes - notes that
unbalance the response of an instrument by resounding much louder
than other notes, because they are octaves or low harmonics of
the fundamental resonant frequency (which is precisely what
Eric's (William Lippe) formula would produce - he just restated
the formula behind the harmonic series). This is something guitar
and fiddle makers strenuously avoid, going instead for general
amplification through resonant bodies. I've never experienced a
true wolf note on a harmonica. An especially resonant note can
usually be traced to the adjustment of the reeds and their
relations to one another.

If you *could* produce a harmonica that amplified the lower
partials of the harmonic series, it would dovetail rather nicely
with a just-tuned harmonica.