Guy Fedorkow

A Microcomputer-Based Conducting System

The subject of this paper is a portable, microcomputer-based performance system that we call the conduct system.1 This system was developed at the University of Toronto as part of the research of the Structured Sound Synthesis Project (SSSP) (Buxton, Fogels, Fedorkow and Smith 1978). The system, built around a microprocessor controlling a digital sound synthesizer, had its genesis in the earlier conductor system of Mathews (Mathews 1976). That is, it is a system that allows the performer to interpret or conduct precomposed score material, rather than a system on which the prime performance task is to articulate each individual note, as is the case with conventional instruments. In the remainder of this paper, we shall provide a description of the microcomputer-based conducting system, concentrating on aspects of the human interface and the control structure. In addition, we shall discuss what we see as the relative strengths and weaknesses of the system, based on our experience with it in both the laboratory and the concert hall. We shall begin, however, by relating our work to that of others in the field, and by discussing the general issues of the problem.

A Computer-Controlled Sound Distribution System for the Performance of Electroacoustic Music

Since the advent of electroacoustic music, and even earlier, musicianshave shown an interest in using the spatial distribution of sound as a significant consideration in composition. Whilethere have been many attempts to realize the musical potential suggested by this possibility, certain problems have intervened. Significantly, these have been primarily in the technological rather than the musical domain. In electroacoustic music, the general problem can be considered to be the evocation of cues which cause an acoustic event to be perceivedat a particular location in acoustic space. Such cues can be considered in terms of two categories: those affecting directional perception and those affecting distance perception. The current paper investigates the problems in the former category, the evocation of angular cues. [2] Following a brief discussion outlining musical motivation, considerations pertinent to the control of directional cues are discussed.Included are both technological and psychological problems. After a survey of relevant approaches, a new system is presented within the context of the Structured Sound Synthesis Project (SSSP) at the University of Toronto. Finally, a working prototype of this new system is presented in order to validate certain of the basic concepts presented.

On Line (Real Time) Quantitative Measurement of Premature Ventricular Beats

A real time system for graphically displaying premature ventricular beat trends is described. The system consists of analog detector circuits coupled to a Fortran based software program for premature ventricular beat processing. The software program runs four independent channels and has three available analysis modes: a “counting” mode which provides a running total of counts to date; an “averaging” mode which displays average number of events overtime, and a “ratio” mode which provides an output reflecting changes in the ratio of premature ventricular beats to all beats. Various scale factors can be applied to accommodate differing background states. The systems strengths lie in its simplicity, accuracy, and simultaneous analog display of both the original ECG signal as well as the derived quantitative data.