Cris Forster
s Instruments and Music


          Acoustic music is the most difficult music. Building musical instruments from the ground up is an expression of freedom and, therefore, an expression of imagination. Nothing about this art is hewn in stone. The creative builder examines all aspects of musical instrument construction, and on a case-by-case basis decides which traditions to keep, and which to throw out.

          I build because the tunings and timbres I want to hear do not exist on store shelves. Robinson Crusoe built because he had no choice. And yet, his creations also had no critics, and so his imagination became his life. Often when I hike through forests or climb mountains, I am reminded that only man knows what time it is. When I enter Crusoe’s world, or when in building an instrument time ceases to exist, I live with the knowledge that success is only a function of thought, work, and patience.

          The desire for perfection is the juggernaut of creativity. All my instruments are flawed. A bar may not ring as long as another bar; a canon bridge may be too high or too low; or a tone hole may be too wide or too narrow. I know where all the flaws are, and could find many more. But what is the point? The only thing that matters is to build and to make a music that is sustainable in time. I was born a musician, and have built musical instruments since 1975. In the words of Walt Whitman (1819–1892), “I . . . begin, hoping to cease not till death.”

          I also hope that these instruments will inspire others to think critically about acoustic music, and perhaps to build an original instrument or two. One of the happiest moments of my life is to finish a project, step back, and declare in a state of complete surprise, “I’d like to meet the person who built this instrument.”



*     *     *



YouTube Just Intonation Music Videos





*     *     *



Kickstarter Article





*     *     *



PTC Mathcad Article





*     *     *



San Francisco Classical Voice Article




*     *     *



We are pleased to announce that Cris Forster’s book,


Musical Mathematics: On the Art and Science of Acoustic Instruments,


is available at click New or Used.




Musical Mathematics is also available in more than 130 libraries, including The Metropolitan Museum of Art, The British Library, Juilliard, Harvard, Dartmouth, Yale, Columbia, MIT, New York Public Library, University of Chicago, Stanford University, California Institute of Technology, San Francisco Conservatory of Music, five U.C. campuses, etc.



Musical Mathematics is the definitive tome for the adventurous musician. Integrating mathematics, music history, and hands-on experience, this volume serves as a comprehensive guide to the tunings and scales of acoustic instruments from around the world. Author, composer, and builder Cris Forster illuminates the mathematical principles of acoustic music, offering practical information and new discoveries about both traditional and innovative instruments. With this knowledge readers can improve, or begin to build, their own instruments inspired by Forster’s creations shown in the 16 color plates. For those ready to step outside musical conventions and those whose curiosity about the science of sound is never satisfied, Musical Mathematics is the map to a new musical world.


Published: Chronicle Books
Release Date: July 14, 2010
Hardcover, cloth case, and dust jacket
Sewn binding
8¾ x 11⅛ x 1.9 in
944 pp
16 color plates
249 figures
105 tables
4 bibliographies
8 appendices
Comprehensive index


Table of Contents  [PDF]

Look Inside!   [PDF]

Bibliography  [PDF]
Index  [PDF]


Seven Reviews  [PDF]
Twelve Short Reviews  [PDF]




*     *     *


July 17, 2008


KPFK, Los Angeles; the Global Village radio program, hosted by John Schneider, with excerpts from our new DVD A Voyage in Music, and CD Song of Myself: Intoned Poems of Walt Whitman, featuring original instruments and music by Cris Forster.


The KPFK Radio Program:



*     *     *



Cris Forster with Chrysalis (1981)

Photo by Norman Seeff





We are pleased to announce the release of our

30th anniversary documentary:


A film by Eli Noyes and Heidi Forster


          This film is a retrospective of Cris Forster’s work over the past thirty years. It presents an overview of the creative life of this prolific musical instrument builder, writer, composer, and performer, and features insightful interviews with Mr. Forster and Chrysalis Ensemble musicians. The documentary also includes detailed chapters on all seven unique instruments with performance excerpts, descriptions of all the music he has composed to date, and a discussion of his book, Musical Mathematics. The film is a lively mix of history, theory, philosophy, and thoughtful commentary on the field of acoustic music.

          The Chrysalis Foundation is proud to support the work of this modern musical master. We will use A Voyage in Music as an educational tool and for audience development. This documentary substantiates the importance of raising funds to support the self-publication of Musical Mathematics and the production of Ellis Island/Angel Island: A Vision of the American Immigrants, Mr. Forster’s current work-in-progress.

          A Voyage in Music runs one hour. In addition, it includes another hour with full performances of eight pieces and a slideshow.










A Voyage in Music, a film by Eli Noyes and Heidi Forster.


DVD: $10.00.


Shipping and handling (in the U.S.): $5.00.