Reeds
The
most important parts of a concertina are the reeds. The reeds generate the
sound, determine the
sound quality, air consumption, dynamics, etc.. Traditional
concertina reeds consist of a reed frame (shoe),
clamp with two screws, and the
reed itself. Besides the different materials used for the reeds, the fit of the
reed in the slot also has an effect on the sound quality. The better the reed
fits in the slot, the better the
sound production will be.
These are two different ways to of mounting a reed on a frame. The reed on the
left with clamp and screws,
is the most common. The reed on the right is from a
Wheatstone from the1870s. The reed is riveted on the
frame. Wheatstone used this
method for both steel and brass reeds. Accordion reeds are riveted in the same
manner.
Reed problems that frequently occur are corrosion of the reeds (steel)
and/or frames, broken or missing reeds,
bent reeds, clamp screws which are
missing, or rusted through.
A standard 48 key English has 96 reeds, which all have to be individually
checked, cleaned, set, and tuned.
Concertinas used to be tuned to 'high' or
philharmonic pitch, which was A= 452.5Hz. Tuning a concertina
down to concert
pitch, A= 440Hz. is very time consuming.
On
the left are three different sizes of brass reeds. On the right three different
steel reeds. The third
variation of material is nickel silver, which was common
in early instruments.
Nickel silver looks like steel, but plays more like brass. The longer the reed,
the lower the note.
In General, the harder the material, the more harmonics the reed produces, which
results in a brighter and
louder sound. The dynamic range also increases with
harder reeds. Steel reeds are the hardest used in
concertinas. They produce a
bright sound. Nickel silver reeds are the softest used in concertinas. They
sound
is rather soft and has very few harmonics. Brass reeds are warmer sounding
than steel and louder than nickel
silver. They also 'color' better than steel.
With coloring we mean the difference in harmonics spectrum
between soft and loud
tones.
Valves, the strips of leather next to the reeds, always have to be replaced. In
this picture you see that the
valves are not laying flat on the reed pan
anymore. One reason for this is the natural deterioration of the
leather.
Storing a concertina in the original hexagonal case also causes the valves to
hang. Because the
instrument is stored on one side, the bottom valves will
eventually hang down.
A concertina has about as many valves as it has reeds (the highest notes are not
valved).
Also note the rust on the reeds (riveted reeds: 1870s Wheatstone)
This instrument has new valves. The size and thickness/stiffness of the valve is
very important. If the
valves are too heavy, they will interfere with the air
flow. When they are too light, the will 'flutter'.
These reeds have been cleaned. Note the difference with the previous picture
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