Category Archives: 31-et

The Spectrum Keyboard

SpectrumKeyboard titlepageThe Spectrum Keyboard is a redesigned music keyboard intended for digital synthesizers, samplers, and other electronic media applications. It is planned as a ‘musical typewriter’, making the playing of chords and scales much easier than the old black-and-white keyboard. This is the first version (1988) of the keyboard built in New York in 1991 called the Terpstra-keyboard.

Click on the link to see the article in your browser or right-click to save the file to your drive.

http://www.siementerpstra.com/writings/Terpstra-SpectrumKeyboard.pdf

 

The Global Keyboards: design specifications

GlobalKeyboards titlepageThe GLOBAL KEYBOARDS refer to a complimentary pair of generalized musical typewriters for computer-based electronic media. Since the design was formulated in 1986 it has been given several names: the Spectrum Keyboards (after a discarded color scheme), the One-Circle Global Keyboards (after an essential parameter of the design), or just my generalized keyboards. The complimentary relation between the two keyboards has also led me to call them male and female.

Click on the link to see the article in your browser or right-click to save the file to your drive.

http://www.siementerpstra.com/writings/Terpstra-GlobalKeyboards.pdf

 

Take Two and Skip One

TakeTwoSkipOne titlepageThe author examines an interesting and neglected set of harmonies that make up the diminished scale. Along the way he demonstrates the usefulness of the Expansion Index as an organisational tool. In addition, he makes some introductory remarks concerning the comparative musical theory of tonal harmony.

Click on the link to see the article in your browser or right-click to save the file to your drive.

http://www.siementerpstra.com/writings/Terpstra-TakeTwoSkipOne.pdf

 

On Dominant Substitutions

DominantSubstitutions titlepageThe author looks at a variety of substitutions for V7 and IVm6 within tonal harmony and why such procedures work. Meanwhile he explores some fundamental issues of music theory.

update (august 2016):  a brief description of Dominant Preparations.

Click on the link to see the article in your browser or right-click to save the file to your drive.

http://www.siementerpstra.com/writings/Terpstra-DominantSubstitutions.pdf

 

On Chord Progressions

ChordProgressions titlepageThe author examines a variety of chord progressions within tonal harmony. In order to better understand the syntax or ‘flow’ he defends a morphological toll called the Reciprocity Model of chord progression. With this aid he looks at some interesting features mainly oriented around the extended meantone fabric of harmony.

Click on the links to see the articles in your browser or right-click to save the files to your drive.

http://www.siementerpstra.com/writings/Terpstra-ChordProgressions.pdf

http://www.siementerpstra.com/writings/Terpstra-ChordProgressionsRotor.pdf

 

On the Circle-of-Fifths Rotor

Rotor titlepageThe author introduces a device that enable the rapid analysis of harmonic functions and related chores. He explains how the idea developed over time in his pursuit of ergonomics, as well as some essential features of the device.

Click on the link to see the article in your browser or right-click to save the file to your drive.

http://www.siementerpstra.com/writings/Terpstra-Rotor.pdf

Terpstra-Rotor12 Terpstra-Rotor19 Terpstra-Rotor31 Terpstra-Rotor53

 

The Laws of Harmonics

LawsofHarmonics titlepageStarting in the middle 1980’s, around the time that I wrote up A Short List of Musical-Cosmological Monochords, I began a patient compilation of diagrams. Most of them consisted of elaborate tables showing numerous just ratios calculated in cents, as well as some speculative monochords and representations of the Harmonic Series. I meant this work to accompany a text that sums up my investigations into Harmonics. Inevitably, it reflected my interests during the seventies and early eighties – just intonation, drone-based music, and monochords. I never got around to writing the text, though I left a couple of pages of notes. After a few years I scrapped the whole project and archived it under the rather imposing heading: The Laws of Harmonics. Recently I dragged it out of its storage to reconsider the project.

Click on the links to see the articles in your browser or right-click to save the files to your drive.

http://www.siementerpstra.com/writings/Terpstra-LawsofHarmonics.pdf

http://www.siementerpstra.com/writings/Terpstra-LawsofHarmonicsDiagrams.pdf