Welcome to Interval Archive

The Interval Archive represents a specific time and place in the history of microtonal music. The time; the last quarter of the 20th Century, the place; the West Coast. This is also the story of the journey of Jonathan Glasier, who has collected and presented this information and chronicled this movement as it happened.

In this microtonal time period, before functioning microtonal electronics which would make the development much easier, there were two specific instrument categories that were mostly used for creating new non-twelve scales for general use, strings and percussion. Other than the violin family of bowed strings, which of course are thoroughly microtonal, plucked strings of the guitar and harp and psaltery strings were used extensively. Microtonal percussion instruments were mostly metallophones and marimbas made of wood, bamboo and glass.

The process of being a serious microtonal creator was very holistic. Once you had created your scale, you would invent and/or build a viable instrument, learn to play it well enough to perform; compose music for the instrument; find a venue for a performance (be your own manager), and usually cover all the details of PR and costs. Harry Partch paved the way, accomplishing many of these tasks and hardships first, so we knew what we were all getting into.

The Interval Archive aggregates the ideas, hardware, and music created by these very enterprising individuals on the West Coast who were all doing this work during the last quarter century. A nod must be given to the microtonal development on the East Coast at the time, mostly pulled together by Johnny Reinhard and Dean Drummond. The emphasis on the East Coast was more about presenting microtonal music by integrating conventional instruments into concerts and presentations. By the 1990’s the Partch instruments were in New York under the direction of Dean Drummond. Microtonality was alive and well during the same time as the activity on the West Coast. It was just a different flavor.

Interval Journal, Issue 1. Spring 1978. Cover features Ivor Darreg with his Megalyra.
Interval Journal, Issue 1. Spring 1978. Cover features Ivor Darreg with his Megalyra.

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Harry Partch was the catalytic spark for the emergence of microtonal activity in the last quarter of the 20th century.

These two facts exist–

  1. There were other important people who were already composing and playing microtonal music, and
  2. The development of the musical synthesizer during that time paved the way for making microtonality more accessible to musicians.

Also Adrian Fokker from The Netherlands shined a light on fellow countryman Christian Huygens, a scientific genius from the 16th century who discovered 31 tone equal temperament. Fokker began developing and sharing it with musicians in post World War II Europe. It became a national movement in that country. Microtonal Music, of course, has always been with us, especially in world music, and some say that all music is microtonal, but with the transition of the keyboard technology from the harpsichord to the piano, the standardization of 12 EDO was pretty much set in stone in the late 1800’s. From that time to recent times, 12 EDO has not only been the dominant scale but has sort of been imbued in our DNA. Is especially true recently since the automatic quantization of twelve in electronic music.

What I witnessed in my life, chronicled in the Interval years, was the well-spring of microtonal activity starting with my very early years, having Partch and his instruments in our household, and later in his ensemble and being one of his assistants at UCSD in the late 60’s. Those experiences launched me onto a pathway of continual discovery and action of gathering material and sharing it through my own music, journalism and production of microtonal events.

Microtonal People

Microtonal people are special in several ways. First of all, the process of creating and presenting microtonal music is a Holistic Endeavor. For example: you create a scale, develop an instrument to play that scale, write the music, often in a non-traditional notation, find someone, usually yourself or someone you can find who is willing to perform it, probably produce it and publicize it yourself. Why? Because it is not a popular idiom and the resources are always very limited. But, you do it anyway because you are that microtonal person that wants to hear and create something that is in a different “mood” or a different flavor. You are not hampered by a language of 12 notes. No, Partch pointed out that there is a “Vast sea between 1/1 and 2/1”. And, we realize that there are non-octave scales and you can use a vast array of math to formulate any scale you can think of. It is that freedom of choice and wonder that drives the microtonal person.

The Interval Archive is about these people during that time period who were driven to step outside the box to create the unheard combinations of pitches that is the focus of this website. You will get a view into the work these people have done creating new scales, new instruments, letters
that they have written to each other, and evidence of their struggles and triumphs. Their work has laid the groundwork for the landscape of microtonal music today which has opened up to a new generation of possibilities.

– Jonathan Glasier (JDG)

Recent Uploads

Handwritten letter from Ivor Darreg to Danlee Mitchell dated 10 October 1985, discussing instruments and life in San Diego.
Ivor Darreg. Letter to Danlee Mitchell. 10 October 1985.
Uploaded October 2026
Handwritten letter page discussing computer music composition, Mac technical issues, and microtonality.
Wendy Carlos. Letter to Ivor Darreg. Page 2, no date.
Uploaded October 2026
Handwritten letter dated October 22, 1963, from Stan Woolsten in Garden Grove, California, discussing Ivor Darreg's PRETERTEMPORALISM publication and experimental art concepts.
Stan Woolsten. Letter to Ivor Darreg discussing PRETERTEMPORALISM and experimental approaches to time and art forms. October 22, 1963.
Uploaded October 2026
Handwritten letter from John Schneider to Ivor Darreg dated April 16, 1988, requesting participation in guitar book project.
John Schneider. Letter to Ivor Darreg inviting his participation in The Well-Tempered Guitar, discussing non-12-tone guitar systems and requesting photographs and diagrams of Darreg's fretting systems and music. April 16, 1988.
Uploaded October 2026
Handwritten letter discussing 19edo and 38edo tuning systems and violin composition
John Nieve. Letter to Ivor Darreg discussing 19-tone equal division and 38-tone equal division tuning systems, violin composition, and frequency documentation methods. 1993.
Uploaded October 2026
Handwritten letter dated March 16, 1989, from Ivor Darreg to Mark Engebretson at Sumit Laboratories regarding loaned synthesizers including Roland, Korg Poly-Six, and Ensoniq Mirage.
Ivor Darreg. Letter to Mark Engebretson disclosing loaned synthesizers. March 16, 1989.
Uploaded October 2026
Handwritten letter page discussing non-12-tone instruments, new scales, and tuning systems in music composition and synthesis.
Ivor Darreg. Letter on non-12-tone instruments and alternative tuning systems. April 30, 1982.
Uploaded October 2026
Handwritten letter dated September 2, 1986, discussing moving plans, health issues, and just intonation cello work.
Ivor Darreg. Letter to David Scheirman discussing relocation to 3612 Polk Avenue, health concerns, and recent just intonation cello experiments. September 2, 1986.
Uploaded October 2026
Cover art for Process Tools Utility publication, June 2026.
Photograph by Shannon Michael Terry

New Album

Process - Tools - Utility

Jonathan Glasier & Shannon Michael Terry

Listen now on Bandcamp. Pre-order the new release and support independent microtonal music.

Megalyra II / Hebdomekontany

Jonathan Glasier & Shannon Michael Terry

Jonathan Glasier experimenting with the Lumatone

Music Lessons

Personalized lessons in-person in San Diego or online anywhere you are. Learn vocal harmonics and 19edo microtonal practice with Jonathan Glasier, and anything about tuning theory and music history with Joseph Monzo.

Musical Instruments Gallery

Explore pictures and recordings of, and information about, microtonal instruments and their makers. Go to the gallery.