That kind of "double soundboard" - a removable "false soundboard" (as described by Montal) was quite common in the early 19th century. I haven't heard it described as a double soundboard, but I suppose it could be.
Montal wrote (in his section on piano history) that Pleyel experimented with veneered soundboards in 1830. This was partly an offshoot of Pleyel's attempt to compete with Erard in the area of the harp, as it was initially done for the harp. Here is that passage:
In 1830, Pleyel introduced veneered soundboards in the piano.
This improvement, which astonished the whole world because
it was in opposition to all recognized ideas, produced,
however, happy results.
Dizy, associated with Pleyel for the fabrication of harps,
had been led by various experiments concerning the resistance
of soundboards to glue a thin board of another wood to an ordinary
spruce soundboard, crossing the fibers to give it more
solidity. His friends and workmen tried in vain to dissuade
him from this attempt, which seemed to them to be folly, but
this professor persisted in his idea. The harp thus built did not
truthfully have more power than an ordinary harp, but the
tone gained in the area of quality. Then Pleyel made a trial of
the same sort on a grand piano, veneering a spruce board in
mahogany, crossing the fibers of the woods. The result was the
same; i.e., the tone did not increase in volume, but acquired a
particular quality that was very satisfactory, the treble becoming brilliant and silvery, the middle penetrating and accentuated, and the bass clear and vigorous.
Regards,
Fred Sturm
"Believe those who seek the truth; doubt those who find it." Gide
Original Message:
Sent: 6/8/2025 7:57:00 AM
From: David Graham
Subject: RE: 1850 Pleyel Petit Patron
There is a pic of a replica Pleyel with double soundboard, which was placed over strings. This pic came from a project recording of two pianos like early Beethoven instruments. They recorded with and without the removal second soundboard which is placed over the strings. I'm surprised it would be found in an instrument that late.
David Graham
Graham Piano Service, Inc.
512 S. Main St.
Sycamore IL 60178
815-353-5450
Original Message:
Sent: 6/7/2025 9:56:00 PM
From: Cy Shuster
Subject: 1850 Pleyel Petit Patron
A customer of mine in Northern Virginia has an 1850 Pleyel that needs restoration. Dr. Aural Betz assessed it from photos as follows:
Pleyel #16163 was completed and sold to Madamme Ducrot in July/August 1850 in Paris for 1800 Francs, less than a year after Chopin's passing. It is the exact small Petit Patron model variant he used late in his life for composing, teaching, and small house performances. (the wood is French burlwood and the original double soundboard is intact). The furniture and finish are remarkably original and in complete condition.
It has had the wrong hammers and strings installed and is currently unplayable because of the touchweight. She's a huge fan of Chopin and would love to find an expert to give it the care it needs, and apparently the double soundboard is unusual.
--Cy--
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Cy Shuster, RPT
Fairfax, VA
http://www.shusterpiano.com
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