On the Physical Correlates of Timbre
James Tenney discusses the physical correlates of timbre using the digital computer technique developed at the Bell Telephone Laboratories. His intention is to synthesize a large class of timbres, first by considering the physical properties of natural sounds as well as sounds produced by conventional musical instruments. He goes on to explore how many different ways that the quality or timbre of a sound may be made to vary perceptibly, and in how many ways the quality of one sound may be distinguished from that of another, given that the perceived pitch, intensity, and duration are held constant. Tenney also talks about certain transient phenomena and various kinds of quasi-steady-state modulation processes which, along with the spectrum, constitute what he calls the three basic parameters of timbre. He examines each of these three parameters into several subparameters.