Tuning melodicas

Does anyone have any experience in retuning melodicas? Are the reeds
easily accessible? How much can they be tuned up or down? Are they
reliably tuneable without changing the timbre?

(I'm writing a piece with Sheng, need some additional pitches, and
thought that a melodica would be a reasonable auxilary instrument for
those pitches).

DJW

--- In tuning@yahoogroups.com, "djwolf_frankfurt" <djwolf@...> wrote:
>
> Does anyone have any experience in retuning melodicas? Are the
reeds
> easily accessible? How much can they be tuned up or down? Are they
> reliably tuneable without changing the timbre?
>
> (I'm writing a piece with Sheng, need some additional pitches, and
> thought that a melodica would be a reasonable auxilary instrument
for
> those pitches).
>
> DJW
>

From my book --

_Musical Mathematics: A Practice in the
Mathematics of Tuning Instruments and Analyzing
Scales_ --

Chapter 6: Bar, Rods, and Tubes

******************************

"To tune the metal reeds of harmonicas, etc.,
carefully insert a thin piece of cardboard between
the reed and the opening of the air chamber. This
holds the reed in place and prevents it from
bending down into the aperture. With a fine file,
remove small amounts of material at the clamped
end to lower F1, or at the free end to raise F1.
Avoid touching the reed because heat will cause it
to sound flat. (See Section 14.)

One notable difference between bars and reeds is
that in the bass sections of harmonicas,
accordions, etc., one frequently finds small masses
soldered to the free ends of metal reeds. Figure 16
shows a clamped-free bar with a mass attached at
the free end. In the confined spaces of small
musical instruments, one cannot use long reeds to
produce low frequencies. Consequently, musical
instrument builders developed this tuning
technique, which significantly lowers the
fundamental frequencies of relatively short reeds.
Mass loading does not work very well on
percussion instruments because the extra mass on
a bar's free end severely dampens vibration. How-
ever, this problem does not apply to wind
instruments because a continuous flow of
compressed air keeps the reeds in motion. The
following equation gives the fundamental frequency
of a clamped-free bar with a mass at the free end."

******************************

I only have experience with harmonica, accordion,
and harmonium reeds.

Melodica reeds should be easily accessible by
simply removing a few screws from the back of the
instrument.

Small reeds are less re-tunable. I would guess that
melodica reeds could be retuned + or -30 cents.
The great difficulty in tuning reeds is providing
constant air pressure. Harmonium reeds can vary
as much as +30 cents just by increasing the speed
by which one pedals the bellows.

Tuning reeds with a fine file will not affect their
timbre.

Cris Forster, Music Director
www.chrysalis-foundation.org