Keyboard characterization using spiral and Cartesian mappings of the harmonic series
Palmyra Catravas · The Journal of the Acoustical Society of America · 2006
Spatial transformations of functions of frequency can facilitate the analysis of frequency spectra and the identification of characteristic spectral patterns. Here, spiral and Cartesian mappings of the harmonic series are applied to frequency spectra from several keyboard instruments (modern grand piano, modern upright piano, fortepiano). Their utility in comparing properties of the instruments, including inharmonicity, coupling between strings, tuning errors, and beat frequencies, and simply identifying a fundamental frequency will be described. An update on a previous application of the transformations (identification of the B-A-C-H motif in music) will also be presented.