The vibrations of the Stuart piano string and its effects on tonal colour are investigated in this chapter. Wayne Stuart claims the Stuart piano sound has an improved dynamic range and clarity of tone because the string vibrates in a more pronounced vertical plane than the modern piano string vibrations. 141 These claims are discussed and tested in the following pages.
The strike of the hammer activates the vibrations in the piano string that produces the basic ingredients of piano sound. A musical sound is produced by the exact repetition of vibrations known as their frequency. Musical pitch is defined by the frequency at which the vibrational period repeats. Galileo’s measurements of frequencies with periodic motion, 142 set the science world on an investigation of the relationships of time and frequency. In the 1960s the Systeme Internationale standardized the measure for pitch as a hertz, named after Heinrich Hertz, the 19th century German physicist who discovered how to generate radio waves. 143
Something which makes 1 complete vibration every second has a frequency of 1 hertz, (or 1 Hz)144
The frequencies and the qualities of tone of the Stuart & Sons piano sound are investigated in this study by understanding the behaviour of vibrations. The string vibrations of the modern piano, represented in this research by the Steinway piano are compared to the vibrations of the Stuart piano strings.
The quality of tone depends on the form of vibration….., every different quality of tone requires a different form of vibration. 145
The Stuart & Sons piano design differs significantly from the modern piano design with the implementation of the bridge agraffe146 . Wayne Stuart makes the claim:
The innovation at the core of the Stuart & Sons design concept is the principle of vertical string coupling, by using a special device (agraffe) to anchor the strings to the bridge. The agraffe defines the strings’ speaking length (frequency) and contains the reaction forces produced by bending the strings as they pass through the agraffe. This allows the soundboard to be designed on a speaker cone principle and not as a load bearing structure as found in the standard piano. This liberates the dynamic range; increases sustain and creates great clarity of tone throughout the entire frequency range.147
141 4Stuart & Sons Handcrafted Pianos. (accessed 14th May 2015).
142Ian Johnston, Measured Tones,The Interplay of Physics and Music.(Bristol & Philedelphia: Institute of Physics,1994),31-35.
143 2Johnston,35.
144 3Johnston,35.
145Hermann Helmholtz, On the Sensations of Tone, (New York: Dover ,1954) ,21.
146Robert (Bob) Anderssen, “The Challenge For the Piano Maker”,The Mathematical Scientist,Isuue 32.2 , Applied Probability Trust,(December 2007): 73.
See also – Richard Dain, “The Engineering of Concert Grand Pianos”Ingenia12, (2002) :15-22
147 5Stuart & Sons Handcrafted Pianos.FAQs qu.2(accessed 8th March 2014).
