Development process of the grand piano duplex scale
Niko Plath, Katharina Preller · The Journal of the Acoustical Society of America · 2017
Acoustical investigations of the earliest examples of implemented duplex schematics allow to shed light on the question of how much of the piano development in the late 19th century was still a trial and error approach or already a methodical process based on empirical findings. Further, it is investigated if the intended effect was instantly perceivable, or if it was first a theoretical concept, which was later refined to enhance a certain tonal character. For a modern grand piano, the influence of the duplex schematic on the vibroacoustic behavior and the aural impression is extensively covered by Öberg and Askenfelt. By performing measurements on several pianos from the late eighteen hundreds, most prominently the so-called Helmholtz piano, a Steinway grand presented as a gift to von Helmholtz in appreciation of the impact of his work on the company’s piano development, it is possible to retrace development procedures in the workshop in that specific time period. Design parameters from the respective pianos are obtained, e.g., string length ratios, angles from main string to front duplex, boundary conditions, and string diameters. Acoustical measurements, as proposed by Öberg and Askenfelt, are performed to examine if these constructive changes have any significant effect on the generated sound and to allow a comparative analysis of both historical and contemporary instruments.