From: AAAI Technical Report WS-96-03. Compilation copyright © 1996, AAAI (www.aaai.org). All rights reserved. Design, Harmony, and Voice Leading GarryS. Sittler University of Illinois at Urbana-Champaign Department of Computer Science Urbana, Illinois 61801
[email protected] Abstract General voice leading rules have evolved with Western This paper describes an automated design system music over time. These rules comein several categories. which harmonizes music. The goal is to take a given Some,such as the available major, minor, diminished, and melody line and produce four part harmonyaccording augmentedtriads, are dictated by the structure and the to procedures set forth by harmonization and voice pitches of the twelve notes within an octave. Others are leading techniques. Voice leading techniques provide based on preferences of what sounds pleasant to the human some guidance about how to produce a musical ear. Manyof these types of rules designate musical arrangement. Manyof these techniques, however, are situations which are prohibited. Another category could be represented by rules which specify certain situations called heuristic knowledge.Several of these rules are based which must be avoided. Thus, the principle challenge is how to determine what design choices should be on what a composer might do, and they are also good made based on what cannot be done. methods for avoiding the prohibited situations. Each category is further explained and exemplified below. Eachof the seven notes in a scale has associated with it a Introduction triad which is formed with the two notes forming intervals of a third and a fifth above it. The possible triads for a The process of automated design involves choosing major scale are as follows: appropriate values for a given set of design parameters.