Pluck
From Audacity Manual
Pluck generates a synthesized pluck tone with abrupt or gradual fade-out, and selectable pitch corresponding to a MIDI note.
Pluck MIDI pitch
MIDI values indicate what pitch to use. Examples:
- C notes are: 24, 36, 48, 60 (middle C, default), 72, 84, 96, 108
- C# (C sharp) above middle C is 61.
Fade-out type
Enables you to choose between an "abrupt" or a "gradual" fade out for the pluck.
Duration [seconds]
Specifies the length of the specified pluck. The default is 1.0 seconds.