Randall Lab. of Phys., Univ. of Michigan, Ann Arbor, MI 48109-1120
Most devices which can be used to ``make sound,'' in the sense of converting frequencies in the range of human gestures to those within the audible band, are nonetheless not in use as musical instruments. What is required in addition is a large, but precise, control parameter space that makes an instrument ``playable,'' that is capable of transmitting a complex musical message. Within this parameter space, the exact control of periodicity is especially important, particularly so in Western music. After first exploring how the requirements of pitch stability, acoustic output capability, and sustaining power are satisfied in various instruments that vibrate freely after an initial excitation, the discussion will continue with the more complex physics of the bowed string and the blown pipe in their various embodiments. In many cases, it will turn out that instruments in actual use are not ``engineering compromises'' but, on the contrary, based on fortuitous cooperation among otherwise unrelated factors. The lecture will conclude with a brief discussion of the computer as a musical instrument.