Decay Characteristics of Piano Tones
Hale J. Sabine · The Journal of the Acoustical Society of America · 1960
Measurements have been made on a high-quality spinet piano to determine the initial amplitude and decay characteristics of the principal harmonic components of notes covering the entire scale. Decay rates of individual components varied from 1 to 100 db/sec as a function principally of frequency and string position in the scale rather than of harmonic number. An exception was noted in the third to fifth octaves, where the fundamental of a given string decayed at a considerably higher rate than the harmonics. This pattern appears to have a strong influence in determining typical piano tone in this region. Frequency spectra of the initial amplitudes of individual notes over the entire scale show, on the average, a sharp cutoff below 100 cps, a fairly flat region between 100 and 1000 cps, and a roll-off of at least 12 db per octave above 1000 cps, with negligible energy above 8000 cps.