Effect of hammershank material properties on piano struck string sound
Jacob Amero, Mario Riccardi, Philip P. Faraci · The Journal of the Acoustical Society of America · 2019
The purpose of this study was to investigate the effects of the hammershank material properties of a piano action assembly on the sound produced by the struck string. Using a standard birch hammershank as a baseline, a CAD drawing was developed from which several test hammershanks were fabricated. Alternate woods such as poplar and red oak, as well as several different 3-D printed filament materials were used. Vibrational frequency response data from 0 to 1600 Hz was collected from each of the hammershanks using a vibration exciter and accelerometers. Decay measurements of the first ten harmonics of the struck string were taken from note C40 (f1 = 262 Hz) on a typical working grand piano outfitted with the baseline and the test samples. Audio recordings of the string decay produced by each sample were also taken for audible comparison. Results will be discussed.