Hi Stéphane
The origional scale, had C5 (52) at 307 mm and there was 0.925 wire on
it. I have no idea whether the wire was original, but I have the entire
data set if anyone is interested. The scale I designed for this put
that same note at 322 mm and uses 0.85 pure sound wire. I am
considering trying modern wire to hear what difference this makes. My
thinking has always been that by 1850 the major players MUST have been
narrowing in on the modern sound. The developing piano industry was then
about 150 years old, there over a hundred builders by the mid 1850's and
we are some 30 odd years away from Steinway getting its sound fairly
well rooted.
As for adding stiffness at the cross over area between the bass and
tenor bridge. If you will remember there was a connector rib between
rib 1 and 2 and the bass bridge more or less goes right in between these
two ribs. I've been experimenting around with 2-3 medium strength
springs mounted in various ways at various spots to see what effect this
has on the overall sound of the piano. I finally ended up with a line
that pretty much goes right between rib one and two and follows very
closely the bass bridge line. One right in the middle of the bass
bridge and one just under the treble end of the bass bridge just about
half way back to the bass end of the tenor bridge. They are mounted on a
piece of rib material that stretches from the bent side rim to the long
side... more or less simulating an extra rib. Its my intention to
install an extra rib that makes this permanent. There is room to
maneuver for such a retro install, but it will be <<fun>> to be sure.
I'm thinking of first trying a dry run with a slightly crowned rib that
only contacts the SB in three places (with 5 mm thick slates) and see
how that goes. The present position of the extra support has opened the
sound significantly, increased sustain and fullness from around F4
downwards. There was no discernible loss of power... if anything the
opposite seemed to be the case.
As to you final questions... the tenor side of the SB tail is floating
with a big piece of extra wood on the upper and lower sides of the
panel. Obviously a mass scheme. The board is in many regards a copy of
the original.. Rib structure is exactly the same, some fanning yes,
tapering from belly rail to tail the same 9 mm to 4 mm. I'm attaching
the picture of the backside of the original board again so you can see
how it looked.
Cheers
RicB
Hello Ric.
Nice to hear all this.
Just one thought. It is my understanding that the mid 19th century
new wave of builders (Blüthner, Bechstein and Steinway) were aiming
for a new kind of piano based on the recently available (in
industrial quantities) English steel, meaning louder instruments
thanks to heavier stringing patterns. Pleyel factory did the same at
the same time (exactly the time Pleyel (son) himself died and passed
the commands to Wolff, who initiated the new stringing patterns). It
is useful to compare C5 length and thickness in pianos of that
period to get a hint about the overall stringing scheme. Here are
some examples from my experience :
For the note C5,
Pleyel 1840 has 295 mm length and 0.850 mm thickness (beware, this
is not the English steel yet, it is that easily bendable iron wire)
Pleyel 1864 has 309 mm length and 0.875 mm thickness (this is
Firminy wire, very close to the modern Röslau wire)
Pleyel 1895 has 355 mm length and 0.975 mm thickness (this is the
heaviest stringing I have met; you should see the soundboard
underneath... a Panzer)
Bechstein 1871 has 326 mm length and 0.875 mm thickness (this is
straight strung)
Bechstein 1871 has 326 mm length and 0.925 mm thickness (this is
cross strung)
Bechstein 1878 has 332 mm length and 0.975 mm thickness
Steinway 1891 has 326 mm length and 0.950 mm thickness
Knabe 1877 has 320 mm length and 1.000 mm thickness
I would like to know where your Blüthner stands. I'd guess around
320 mm and 0.875 mm, and as such, it would be reasonable to think
that the
intention was a modern sound (for that period).
What did you do to the soundboard for adding stiffness? Add weight
underneath? And this "improved" the bass, causing more lower partials
volume? I would have guessed that it would increase the tenor
sustain, at the cost of volume. Does the instrument have a sort of
floating bass design? Tapered board in that region? Fanned ribbing?
Best regards.
Stéphane Collin.
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