BLUEBOOK OF PIANOS
CONSTRUCTION AND SCALE DESIGN
AND TRAP WORK
The next step, and
one of the most critical in the making of a fine
piano, is the shaping of the treble and bass bridges.
The bridges, of Northern hard maple, must be planed
to exact thickness from end to end, so as to provide
the proper down-bearing of the strings upon the
bridges. It is this correct down-bearing which is so
vital to the transfer of the string vibrations to the
soundboard (resulting in pleasant piano tones).
should be glued to the sounding board with hot hide
glue and further secured with wood screws from the
back. Such screws should have maple buttons under
their heads. The bridges must be accurately notched,
at both top and bottom in the case of treble bridges,
for each individual note. This provides for the
"stopping" of the string at a precise point
in much the same way as a violinist "stops"
his strings be fingering. Bass bridges are planed on
both edges for the same reason.
A time and
money-saving way to do this important bridge notching
is to notch the treble bridge on the top edge only.
Half the work, half the cost and many piano buyers
can't tell the difference unless they are able to
distinguish subtle differences in piano tone.
AND TRAP WORK
manufacturers offer three pedals. On most vertical
pianos the pedal to the right is a full sustain pedal
and by depressing it, the piano tone will linger on
or sustain the note. The left pedal is known as the
"Una Corda", which softens or limits the
power of the tone by moving the action forward and
limiting the distance the hammers travel. On a grand
piano it shifts the action slightly, enabling the
hammer to strike fewer strings.
A third pedal in
the middle varies from brand to brand. It may serve
to sustain the bass notes only, or it may act as
another form of soft. In some cases, it drops a piece
of felt to provide a muffler, or practice pedal.
On a grand, it
becomes a true "Sustenuto", that is,
allowing the pianist to sustain many notes as long as
the pedal is held. A good way to tell about the
quality of a piano is to hold a pedal in your hand
and get a feel for it. Twist it and push it, then go
to a more expensive piano and compare. You'll see the
difference in quality.
As a final point of
clarification, many very fine pianos in the world
only have two pedals, and for many years many
American pianos including Steinway only used two
pedals on many verticals. The center pedal on
vertical pianos is an extra feature which can be a
mute, a form of soft, or even a bass sustain. There
is nothing wrong with having two pedals on a piano.
For many years, that is all anyone had.
© 2009 The "Original Bluebook of Pianos All Rights Reserved