COMPOSER, MUSICIAN AND INNOVATOR
John Chowning’s discovery of digital FM synthesis stands as a pivotal moment in the evolution of electronic music. His groundbreaking work offered unprecedented control over sound generation and laid the foundation for countless innovations that followed. In our eyes, Chowning’s contribution is immeasurable.
FM synthesis, a technique that modulates one oscillator’s frequency with another, produced new complex and dynamic timbres previously unattainable. This marked a departure from the limitations of analog synthesizers, offering composers a new level of precision and creativity and a fresh palate of unique sounds. The impact on electronic music is undeniable, from early experimental works to contemporary pop hits.
EMEAPP’s mission to educate and preserve electronic music history is deeply intertwined with Chowning’s legacy. By understanding digital FM synthesis, students and researchers gain a comprehensive perspective on the evolution of this electronic sound. Moreover, preserving the instruments of early FM synthesis is crucial for documenting the history of the technology based on Chowning’s work.
John Chowning’s discovery and development of digital FM synthesis is a cornerstone of electronic music, its impact on the genre is profound, and its legacy continues to shape the sonic landscape.
We had the rare opportunity to chat with John to discuss his life and innovations. Enjoy this video of Mike Hunter’s EMEAPP interview and the accompanying article written by Lisa Platow. While you’re here, take a gander at some of the flagship instruments in our collection that include Chowning’s digital FM synthesis work. Enjoy!
Some of the instruments in our collection that utilize FM synthesis
John Chowning, the Father of FM Synthesis
Lisa Platow
As he celebrates his 90th birthday this month, John Chowning describes the amazing coincidences that shaped his life and work and shares some of his “life lessons” with EMEAPP
Long before he discovered FM Synthesis, John Chowning’s musical aspirations began, like those of so many other American schoolchildren, in an elementary school orchestra. At eight years old, he took up the violin, learning to read music but never growing super fond of the instrument itself. Chowning’s high school band teacher, faced with a lack of cymbal players, asked if Chowning would mind switching instruments – no doubt thinking that the fact that Chowning could already count and read music made it much less likely that he would mess up by playing a big cymbal crash at the wrong time. As a new member of the percussion section, Chowning soon decided that drums looked like a lot more fun than cymbals so he started teaching himself to drum. Chowning finally found his musical passion when an instrument salesman came to his school to give a demonstration of drum-corps-style rudimental drumming: it was “this super precise drumming that set my mind afire.” Chowning tracked him down after the demo and asked if he could study under him. This taught Chowning the first of what he considers his important life lessons: “if I was really passionate about something, I could do amazing things.” Chowning became a top-notch rudimentary drummer and his high school life soon revolved around singing, drumming, and band class….which meant that unfortunately, his academics took a back seat.
After (just barely) graduating, Chowning decided to enlist in the military instead of waiting to be drafted into the Korean War. Again his musical talent led the way: he was accepted into Navy music school and then spent three years on an aircraft carrier as part of a jazz band. He was astonished by the high level of musicianship displayed by his fellow band members and since being a great rudimental drummer did not necessarily translate to being a good trap kit/jazz drummer, he found himself working his “butt off” to get his skills to where they needed to be to keep up with the rest of the band. This was his second life lesson: “Put your mind to it, practice like hell, and you can get something done.”
He applied that lesson again after he left the service: with his newly-earned GI Bill benefits, he decided to attend college to study music. Unfortunately, his high school academics were so lacking that he was only admitted to Wittenberg University provisionally, with the requirement that he had to make a C average the first semester. Again, he put his mind to it, “worked his butt off” and ended up making all A’s (much to the surprise of the university who actually briefly suspected him of cheating!) He eventually graduated with a degree in music theory and composition and left for Paris to study under Nadia Boulanger, a famous French composer who also taught the likes of Aaron Copland and Philip Glass. While in Europe, he experienced a moment that would change his life forever:
“While I was in Paris, I attended a concert where I heard a piece by Karlheinz Stockhausen called Kontakte, a four-channel piece which he made in a studio in Cologne with a rotating loudspeaker and four microphones on a table. He recorded these rotational movements of sound moving in space that really caught my ear and I thought someday I would like to write music for loudspeakers where the loudspeaker is the purpose. In those days, except for Les Paul and Mary Ford, loudspeakers were for reproducing television shows and concerts and whatnot. But actually making music for loudspeakers where the loudspeaker is the point was relatively unknown.”
Interestingly, Stockhausen’s performance, though so inspiring to Chowning that it would ultimately shape the rest of his career, was not well-received by the rest of the audience: the “traditionally-minded” musicians and students actually booed and hissed at the end of the piece. Thankfully, Chowning’s teacher Boulanger turned out to be more progressive than he expected and to his relief, she encouraged him to pursue his newfound interest in “loudspeaker music.” But he soon discovered that without a specialized studio full of very expensive equipment, he had no way to emulate the magic he heard in Stockhausen’s performance.
He returned to the US and enrolled in a doctoral program in music composition at Stanford University but again, it seemed his dream of creating loudspeaker music would elude him: “I was really disappointed that there was no facility for or even interest in electronic music of any sort.” Resigning himself to studying traditional music, he became a timpanist in the Stanford orchestra, where he stood next to a fellow percussionist, Joan Mansour, who was a biologist by trade. She and Chowning talked regularly during breaks and at one point he mentioned his interest in electronic music inspired by that life-changing concert in Paris. A few months later, in another moment that would shape Chowning’s life forever, Mansour brought him an article she had cut out of Science magazine because she thought it might interest him. The article, called “The Digital Computer as a Musical Instrument,” was by a young scientist at Bell Labs named Max Mathews. Rehearsal was about to start so Chowning shoved the article in his pocket and promptly forgot about it until a few weeks later when he rediscovered the crumpled paper and began to read it. “Unfortunately, I understood very little, but what I did understand was this diagram that had a computer, a digital-analog converter, and a loudspeaker.”
Staring at that diagram, Chowning suddenly realized that if he could simply learn to program a computer, all of that expensive technical studio equipment that he lacked access to would no longer be necessary to make the kind of electronic music he wanted to make.
Luckily for him, he was enrolled at Stanford and one thing Stanford did have back in the early 60s was computers. One of the earliest courses offered by Stanford’s newly-formed computer science department was a programming course for non-technical people, and Chowning, along with a few hundred of his fellow non-mathy, non-engineer students, was soon happily programming in ALGOL. Armed with his newfound programming skills, Chowning visited Max Mathews at Bell Labs to ask if he’d be willing to help Chowning set up the Music 4 computer system described in his paper on one of Stanford’s mainframes.
Mathews handed Chowning a box containing a stack of punchcards and a compiler and sent him on his way with a stern warning: “Don’t drop the cards!” Chowning returned to Stanford…where he quickly realized his ALGOL skills were nowhere near up to the task of turning a box of punchcards into a functioning system. In another life-changing bit of happenstance, as he was standing there wondering how he would ever get Mathews’ program to work, Chowning saw the tuba player who sat next to him in the Stanford orchestra walking by.
As it turned out, this tuba player, a man named David Poole, happened to be taking a high-level class in LISP and AI and offered to help Chowning get things running. Chowning refers to Poole as “my angel” – Poole took him under his wing and taught him everything he needed to know, from the definition of bits, bytes, and core dumps through how to program in a newfangled language called FORTRAN – and together Poole and Chowning created the first version of Music 4 ever to run on a DEC PDP-10 mainframe. Chowning makes a point of saying that everything he’s been able to do in his lifetime can be directly traced back to the moment he ran into Dave Poole outside the computer lab that day and says he will be forever grateful for Dave’s help.
Once Chowning had the Music 4 program running, he set out to accomplish his longtime goal of “loudspeaker music” – he wrote a FORTRAN program to reproduce Stockhausen’s 4 channel system but instead of just moving the sound rotationally, Chowning’s program was designed to move the sound in any direction or pattern the user desired. Chowning discovered something that he called the distance cue: by essentially changing the intensity and direction of the original sound while keep the intensity of the reverberation (which he created digitally) constant, a listener sitting in the middle of 4 speakers could be tricked into perceiving the sound as moving in space around him and actually originating from a distance far outside where the speakers are placed.
With this program, Chowning had essentially accomplished what he had set out to do so many years before when he first heard Stockhousen’s piece, and he began composing pieces that incorporated this new way to move sound around the room. But being a problem solver by nature, he also continued to look for ways to improve his system – and it was this search for improvements that led directly to his discovery of FM synthesis.
Because the listener’s brain being able to perceive reverberant echoes of the original sound signal was so important to his distance cue programming, Chowning decided to focus on ways to make the reverberant field more easily distinguishable from the original sound source. He had noticed that, particularly with simple sound signals like sine waves, the digital reverberant signal that his program produced sounded too similar to the original and thus the distance cue did not work. From his background as a violinist, he was familiar with the effects that adding vibrato to a note could have and he thought that perhaps adding vibrato to the original sound signal would give it enough unique character to help make the reverberant signal more distinguishable from it. He modified his program so that an additional sine wave could be used to subtly vary the pitch of the original signal, creating a vibrato effect. That worked and he was pleased with the results from a distance cue perspective.
But then he realized something interesting – while vibrato on a physical instrument like a violin is limited to the speed that musicians can move their hands (e.g. 6 or 7 times per second), a computer would be capable of speeds far faster than that. Chowning wondered what that would sound like, so he decided to increase the speed of the sine wave controlling the vibrato to 20 times per second, then 80 times per second, then 100 times per second. He noticed that as the vibrato speed increased, instead of perceiving the sound moving in space per the distance cue formula, the sound itself seemed to change. He began to perceive almost a motorboating/vibrating effect that gave the sound a different timbre. He decided to increase the vibrato speed to 200 times per second and also increase the amplitude of the sine wave controlling the vibrato so that it was the same as the original tone. Immediately, this combination of one simple sine wave controlling another (2 oscillators total) produced a seemingly-impossible complex tone with lots of harmonics – something that would require at least 8-10 oscillators to produce with the then-available additive synthesis technology. Excited by his discovery, Chowning spent the entire night experimenting with different frequencies and speeds: he would make a request to the computer and often have to wait several minutes (due to processing power limitations and the fact that he was sharing the mainframe with other users’ jobs) for the resulting sound to come back. During each wait, he would eagerly start thinking about the next set of frequencies he wanted to test. He documented all of his experiments and recorded the resulting sounds but, having no formal training as a scientist, he failed to include the date on his notes, so ironically no one – not even Chowning – knows the precise date of his momentous discovery.
A few weeks later, while visiting the East Coast for the Christmas holiday, Chowning stopped into Bell Labs and showed his new discovery to Max Mathews and Jean-Claude Risset. Risset reproduced John’s steps and took his own notes, which he dated December 18, 1967. Mathews and Risset were impressed and Risset ended up using the technique (which he called “sine sweeping”) in his composition Mutations, released in 1969.
It wasn’t until Chowning’s mentor Dave Poole made the connection that using one frequency to control another (although not in the audio spectrum) was exactly how FM radio broadcasting worked that the name FM synthesis was born.
Chowning soon found himself spending all his time attempting to coax different tones out of his new technology. With no training as a scientist, he approached FM as a “discovery of the ear” – he simply adjusted frequencies and modulation rates until he found the tone he was looking for. He found that combining one or two carrier signals (generating the sound) and one modulation signal (creating the vibrato effect) and putting it all inside an amplitude envelope could create the sound of almost any musical instrument. Once he was able to get incredibly realistic brass tones that were far better than what was available using additive synthesis techniques, he realized his discovery would likely have commercial value: “there was no electronic instrument at the time that could do this.”
He contacted the Office of Technology Licensing at Stanford and suggested they look into potential partnerships with music instrument manufacturers. Stanford contacted the three big U.S. organ manufacturers of the day, Hammond, Lowery, and Wurlitzer, and all three companies sent engineers to investigate the new discovery. The engineers were amazed at the sounds Chowning was producing but had no understanding of computers or the digital domain at all and could not see any way their companies could incorporate the new technology. Stanford then reached out to Yamaha, who was back then the largest musical instrument manufacturer in the world (building 180,000 organs per month in Asia) but did very little business in the United States. Yamaha turned out to be far more technologically progressive than the American manufacturers: they had already been investigating digital control for their instruments and had been studying Max Mathew’s work on digital sampling. They sent an engineer named Kazukiyo Ishimura who looked at Chowning’s code and listened to the sounds he was generating. In less than 10 minutes, Ishimura fully grasped the technology and the potential applications for it. Less than two months later, Yamaha reached an agreement with Stanford to license the FM synthesis patent for further development.
In the meantime, Chowning had been busy attempting to earn tenure as a professor of music at Stanford. He had published a paper on his sound spatialization techniques in 1971 and followed it up with a paper on FM synthesis in 1972. He was also busy composing and releasing pieces that incorporated his new developments. His piece Sabelithe, which he had begun composing in 1966 but did not finish until 1971, became his first piece to incorporate FM synthesis. He also composed Turenas, a capstone of his work both in FM and in sound spatialization that featured amazing FM-generated soundscapes that morphed into other sounds while moving in three dimensional space.
Like Stockhausen before him, however, Chowning found the rest of the academic musical community to be less than enthusiastic about his pieces. The idea of making music with only a computer and a set of speakers was an anathema to many of the traditionalists in the Stanford music department, and unfortunately for Chowning, some of those traditionalists served on his tenure committee. After six years as an assistant professor, Chowning was told to find another job.
Fortunately, Chowning was quickly sought out by IRCAM, a French Institute then being founded to research avante-garde music and acoustic techniques. IRCAM was headed up by a conductor/composer named Pierre Boulez who had previously been director of the New York Philharmonic and chief conductor at the BBC Symphony Orchestra. Perhaps it was the fact that Chowning was suddenly hanging out with such a prestigious orchestrally-trained musician (or maybe it was the fact that someone with such a refined musical pedigree would associate himself with an institute for electronic music in the first place) – but slowly the mindset of the academic world began to shift. The University of California San Diego recognized Chowning’s increasing fame in the world of electronic music by offering him a full professorship – an offer which Stanford, no doubt recognzing the error of their ways as Yamaha’s FM licensing money began to pour in, matched. Chowning thus became the only Stanford faculty member ever to go from assistant professor to full professor without the usual intermediate step of associate professor.
Meanwhile, Yamaha had been diligently working on bringing FM synthesis to market – a task that proved much more daunting than their engineers first suspected. The biggest obstacle was developing hardware that could replicate all of the functionality of a huge mainframe computer inside a portable keyboard, and so a long and busy seven years passed between Yamaha’s initial licensing of the technology in 1973 and release of their first commercial FM product, the GS1, in 1980.
The GS1 was approximately the size and shape of a miniature grand piano, weighed a bit less than 200 lbs, and retailed for approximately £12,000. It offered about 500 preset FM-generated sounds that could be changed by swapping out small magnetic foil strips. There was no way to create your own sounds or even edit the existing presets (not that editing would have been easy, since familiar analog synthesis ingredients like oscillators and filters had been replaced by digitally processed math equations.)
The GS1 was adopted by successful bands such as Toto, but its enormous size and cost limited its commercial potential and Yamaha ended up selling only around 100 units total.
That would all change in 1983 when Yamaha released the DX7.
In just three years, Yamaha had managed to improve FM synthesis technology by leaps and bounds: what had taken approximately 50 expensive integrated circuit chips to accomplish in the GS1 had been reduced to only two in the DX7. The DX7 offered 6 operators and 32 algorithms, allowing programmers to create sounds that had never been heard before. Its 16-voice polyphony far exceeded that of competing analog synths like the Prophet 5 and Jupiter 8. The DX7 included 128 preset sounds that were unlike anything musicians had been able to access up until that point, and owners who weren’t happy with the built-in presets could purchase additional presets on ROM expansion cards. Particularly adventurous and technically-minded owners could modify the preset sounds or even create their own sounds from scratch (although programming the DX7 was notoriously difficult and many users ultimately gave up.) The DX7 was small and portable and retailed for less than £1500, an almost 90% discount off the GS1’s sale price. The DX7 became one of the best-selling synths in history, with more than 200,000 units sold, and the sounds it produced became synonymous with 80s pop music: in 1986, a DX7 appeared on more than 40% of the number-one singles in the Billboard Hot 100.
Thanks mainly to the runaway success of the DX7, Stanford University ended up collecting well over $20 million dollars in revenue from Yahama’s licensing of the FM synthesis patent. To this day, Chowning’s discovery remains one of the most profitable inventions to come out of Stanford University (rumor has it that Yamaha’s FM revenue is eclipsed only by Stanford’s patents for gene editing and Google).
In 1974, Chowning, certain that his electronic music research would never be fully accepted by the traditionalists in the Stanford music department, had used some of Yamaha’s earliest licensing payments to create his own division at Stanford. Called the Center for Computer Research and Musical Acoustics (abbreviated to CCRMA and pronounced “karma”), it remains one of the world’s top research centers for studying audio technology, computer music, synthesis, acoustics, signal processing, and, as you might expect given Chowning’s first love, sound spatialization techniques. The subsequent millions of dollars that Yamaha paid in FM licensing fees were judiciously invested by the university’s portfolio manager and continue to support the work of CCRMA to this day.
As for Chowning? He never let his success go to his head. He continued teaching, researching, and serving as director of CCRMA at Stanford until his “retirement” in 1996 (now a Professor Emeritus, he continues to lecture and research at Stanford and elsewhere.) In 2011, he released Voices, an epic composition featuring the vocals of a live soprano processed in real time by a computer program that integrates all of Chowning’s sound spatialization and FM synthesis work.
And these days, at 90 years old, he still continues his work, doing what he loves every day. Right now he is busy developing what he calls “a digital playground” for users to explore FM Synthesis. He is still actively composing and has several pieces currently in the works. He also has a busy international travel schedule that includes appearances at concerts of his works, visits with friends and family, and lectures at various conferences and academic institutions (including the college attended by one of EMEAPP’s summer interns, which is ultimately how we were able to get in contact with him for this interview!).
Which brings us to the last, and perhaps most important, of Chowning’s life lessons: “I love my work…..I don’t stop. The point is, just keep moving.”
