This article presents a primary-source study of the Pleyel Grand Patron, the first concert grand piano in history, conceived by Camille Pleyel for the 1855 Paris Exposition Universelle. The serial numbers and destinations of the first eight instruments sold by Maison Pleyel at 3,200 francs are documented, together with the history of the sole surviving original — instrument #23825, built in 1856 and rediscovered around 2010 in Italy after more than a century of obscurity in a Buenos Aires warehouse. Of particular interest are the first-hand measurements of #23825 performed by the author during her thesis work at the Santa Cecilia Conservatory: total length 285 cm, speaking (suspended) string length 212.2 cm — only 11.8 cm less than the modern Fazioli F308, currently the longest production grand piano in the world. These measurements, never published before because the Pleyel Grand Patron instruments were believed lost, place the birth of the concert grand piano in a new historical light. A web-readable version of this article is available at http://www.margaretpenn.it/tuning.htm Note: Margaret Penn is the professional name of Virginia Zani, under which the diploma in piano tuning and technology cited herein was conferred. The photograph in Figure 1 (original action of Pleyel Grand Patron #23825) is © 2017 Oreobambo, and is released by the rights holder for reuse under Creative Commons Attribution terms: it may be freely reproduced and reused provided that attribution to "Oreobambo" is given.
Margaret Penn (Wed,) studied this question.