Playing a virtual drum from a real one
Miller Puckette · The Journal of the Acoustical Society of America · 2011
An electronic musical percussion instrument is described which can be played by tapping or otherwise playing on a small physical object, whose vibrations are picked up and used to activate the virtual one. To do this, a ceramic tile or other small rigid object is attached to a contact microphone. Any resonances of the physical system are filtered out using linear predictive analysis, so that the resulting residual signal approximates the excitation the player introduces into the system. The resulting audio signal could then be forward filtered to recover the tile's own sound, but instead it is fed into a nonlinear reverberator to simulate a variety of real or fanciful percussion instruments. The result is a highly expressive and playable electronic percussion instrument, that is, both easy and inexpensive to build. The effects of various design parameters of the nonlinear reverberator on the resulting sound are discussed.