Even steady-state musical notes vary in amplitude envelope over time.

Evidence

The timbre of a principal organ stop sounds “steady” during a prolonged note such as that plotted, which lasts for approximately 2 seconds, but it is clear from the acoustic pressure waveform plot in Figure 5.1 that the ampli­ tude, or “envelope,” varies even during the so-called “steady-state” portion of this note. This is an important aspect of musical notes to be aware of when, for example, synthesizing notes of musical instruments; particularly if using looping techniques on a sampling synthesizer. — David Howard, Jamie Angus, coustics and Psychoacoustics, 1464 (#corroborates, via linked claim)

Categorization

• XREF: connects to: Even identical instruments playing in unison produce uncorrelated waveforms.; A steady-sounding note still has amplitude envelope variation within it — David Howard, Jamie Angus, coustics and Psychoacoustics, 1464; All information-bearing sound must vary over time

Broader Connections

• A steady-sounding note still has amplitude envelope variation within it #corroborates (0.95) — David Howard, Jamie Angus, coustics and Psychoacoustics, 1464