Abstract

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The design of computer-assisted instruction (CAI) software for music theory using Cycling 74's Max/MSP is perhaps best described as an art-science. Of course, programming skills, an understanding of human interface design theory, familiarity with multimedia techniques, are some of the usual prerequisites. But a keen eye for visual organization may be just as important when it comes to designing CAI software applications with Max/MSP. The ability to create a human interface that appears well-organized to the end user, yet has efficient code at its base, is a huge challenge. This paper will discuss techniques and strategies associated with building CAI applications using Max/MSP. The author will first describe how to create a simple CAI MIDI application prototype and then discuss design issues surrounding his own full-featured audio application String Length and Pitch Interval (SLAPI), a just interval player and tuning calculator for Windows and Macintosh computers.

Download

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1. Download the Presentation Handout (pdf)

Presentation Examples

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1. Chord Quality Self-Test MIDI application prototype
2. String Length and Pitch Interval - a just interval player and tuning calculator

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“JUST INTONATION is any system of tuning in which all of the intervals can be represented by ratios of whole numbers,
with a strongly-implied preference for the smallest numbers compatible with a given musical purpose.”

The Just Intonation Network
www.justintonation.net

What SLAPI Is

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String Length and Pitch Interval (SLAPI) is a just interval player and tuning calculator. It was built using Cycling '74's Max/MSP to run as a standalone application on Windows and Macintosh computers. Inspired by the monochord, it provides users with a convenient way to play pitch intervals based on rational string length divisions. The term rational refers to rational numbers, fractions involving whole numbers. Whole number ratios are associated with the harmonic series and serve as the foundational units of historical tuning systems such as Pythagorean and Just intonations. Using two proportional (i.e., not to scale) string length diagrams, SLAPI provides a context for the exploration of the relationship between string length and pitch interval by allowing the user to divide a string diagram into two segments and to play the pitch interval corresponding to the left segment by clicking on the diagram. Using SLAPI, user can play intervals such as 2:1, 3:2, 4:3, 5:3, 5:4, 9:8, 10:9, 81:64, 243:128, and so forth. Any interval in the range 1:1 to 9999:9999, inclusive, may be played and aurally and quantitatively compared to its twelve-tone equal tempered counterpart.

SLAPI shown in Max/MSP's patch edit mode.

What SLAPI Does

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Enter a just frequency ratio via the menus or number boxes provided and SLAPI will:

1. Express the ratio in simplest terms.
2. Calculate the ratio's equivalent decimal form.
3. Draw two proportional string length diagrams (not to scale) called String 1 and String 2.
4. Express the ratio's component pitches in U.S. Standard Pitch Notation and component frequencies in Hertz (Hz.) or cycles per second.
5. Determine the ratio's nearest 12-tone equal tempered (12TET) counterpart and display it on a two-octave piano keyboard diagram.
6. Calculate the ratio's size in cents.
7. Calculate the ratio's deviation from 12-tone equal temperament in cents.
8. Allow the user to play the component pitches of the ratio and its 12TET counterpart individually or simultaneously.

SLAPI - a just interval player and tuning calculator
built with Cycling 74's Max/MSP.

References

Links

1. Cycling '74
2. The Just Intonation Network
3. An Introduction to Historical Tuning and Just Intonation Explained by Kyle Gann.
4. Monochord entry in the Virginia Tech Multimedia Music Dictionary by Richard Cole and Ed Schwartz.
5. A Brief History of the Monochord by Jeff Cottrell.
   

Updated: January 21, 2006

Copyright © 2004 Reginald Bain
All rights reserved