Onset transient significance in listener identification of pipe organ stops

Abstract

Pipe organs typically contain many ranks of pipes, but it is uncertain whether listeners can discern the often subtle differences between different ranks. The importance of onset transients in timbral identification is well established, but in many pipe organ listening situations, the transient is obscured. This paper explores the significance of organ pipe onset transients in an experiment based on Berger’s work on orchestral timbre (K. W. Berger, J. Acoust. Soc. Am. 36, part II, 1888 (1963)] Listeners familiar with the pipe organ attempted to identify recordings of single organ pipes, representing commonly found types of organ stop. Each pipe was presented on different occasions with its own transient and with artificial transients created by amplitude ramps. The results demonstrate that when onset transients are present, expert listeners are adept at identifying the general tonal nature of a stop, but are less adept at precise identification. Replacement of transients with amplitude ramps resulted in a decrease in both precise and general correct identification. The subjective mapping demonstrated between pipe names and their spectral features is explored. Onset transients are shown to be important in listener identification of pipe organ stops.