Category Archives: Sacred Geometry

Means and Music, the generation of the consonant ratios of music through the application of means

Means titlepageThe Pythagorean theory of music was centred around the concept of means. This is understandable, given that all of the ancient Asian cultures saw life as a play of opposites. The Chinese postulated that life is created and balanced through the polarity of the yin-yang. The Babylonians, Egyptians and Greeks also saw life as a dynamically balanced “middle path” between opposites.

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

Means to Music, the generation of the musical ratios through the application of means

Means2 titlepageWe usually understand the ratios of JI as derived from the Harmonic Series. Any Just interval can be viewed as a frequency ratio between two whole numbers, numbers which refer directly to the Series itself. However, it may not be generally appreciated that there is also an alternative way to generate the Just ratios. This method has great historical importance as well as being of intrinsic interest in itself. I refer to the procedure of examining the mean between two extremes.

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http://www.siementerpstra.com/writings/Terpstra-Means2.pdf

The Meaning of the Tetractys – Musical Symbolism in Pythagorean Arithmology

Tetractys titlepageThe Tetractys  symbol is an exquisite example of how a simple visual pattern can have multi-varied meanings and ‘levels’ of interpretive significance. The famous Pythagorean oath refers to the Tetractys, praising it as the source “which contains the fount and root of eternal nature”. A profusion of insights can be derived from the image, concepts which are relevant to arithmetic (number relations), harmonics (musical tuning theory), and geometry (number relations in space). Only a pitifully small amount of ancient commentary has been perserved; but the study of the above disciplines uncovers more and more relevance for the symbol. In this short paper, I will briefly review some historical interpretations and offer a few insights of my own that come from extensive work in harmonics and sacred geometry.

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-Tetractys.pdf

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

Technical Drawings of the Geometric Mean

These diagrams show how the Geometric Mean can be used to find the fret positions for various temperaments. There is mention of it in various papers, namely

http://siementerpstra.com/introductionmonochord/
http://siementerpstra.com/aristoxenus/
http://siementerpstra.com/ptolemy/
http://siementerpstra.com/lawsofharmonics/

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