Hearing the Future with CSound

Matt Moldover
July 12, 2001
Professor Richard Boulanger, Berklee's resident CSound evangelist, joined the faculty in the mid-1980s.
A CSound user created a Hammond B3 organ with drawbars capable of generating additional harmonics. By adding an extra overtone between each pair of overtones, the user built an instrument that possesses a greater range of timbres than a standard B3.
"The CSound Book" is published by MIT Press.
Boulanger demonstrating Max Matthews' radio baton in his Alternate Controllers class.

I remember marveling at music technology when I was a kid. Whenever I got the chance I would fiddle with guitar pedals or a keyboard synthesizer for hours. Today as a music synthesis student I work with technology every day, but I still marvel.

For a modest price, anyone can go out and buy a box that digitally models the architecture of classic analog synthesizers like the Hammond B3 or the Mini Moog. You can buy a box that will correct a singer's pitch, completely change subtle aspects of the voice, and harmonize it, all in real time. You can buy a box that faithfully emulates every element of a recording studio, from mixers to effects to the sound of a microphone made in 1969.

Now imagine all of those boxes crammed into one. Imagine squeezing all of the functions of that one box in one computer program that can run on any home computer. Now imagine that the program is free. Well, you can rest your imagination as soon as you get a copy of Csound.

Csound is the world's most powerful software synthesizer and signal processor. It can do all the things listed above and infinitely more. Written in the programming language "C" in 1986 by Barry Vercoe, CSound is the grandchild of the first computer music programs, Music I-V, written by Max Matthews at Bell Laboratories starting in the 1950s. (You can hear a few CSound compositions by following the links in the left hand column.)

The software can run on virtually any operating system and gives users the ability to create and manipulate completely new instruments in any way imaginable using every known synthesis technique. For example, if you wanted, you could record a sample of your dog barking, pipe it through a model of a forty-foot rubber saxophone, time-stretch it to four minutes in length and filter it with the vocal tract of an 80-year-old man. Or you could startly simpler, perhaps by doubling the number of overtones your Hammond B3 organ can generate.

So if Csound is the most powerful and flexible music program ever, and it's free, why hasn't it put all those music software companies out of business? Because mainstream users have found it difficult to learn and its power and nuance hard to get a handle on.

But there's good news for aspiring CSound users, as Berklee Music Synthesis Professor Dr. Richard Boulanger is on a worldwide mission to help demystify the program for composers and sound designers.

"When you first look at Csound it's like looking at a very technical textbook," Boulanger says. "Software synthesis looks like programming and a lot of people think 'that's grad school' or 'that's math class again.' It turns out not to be that hard at all. You just have to think a little differently."

Boulanger is one of the world's foremost authorities on the Csound language and is the editor of The Csound Book: Perspectives in Software Synthesis, Sound Design, Signal Processing, and Programming (MIT Press, 2000). It is not only a definitive guide to Csound, but an encyclopedia of computer music and a doorway for musicians into the world of software synthesis. Created for sound designers and composers, "The CSound Book" is the culmination of Boulanger's 20 years of doing research and gathering input from the global network of CSound experts. He organized the information in the volume with the intention of making it possible for "musicians and synthesists to relate."

MIT asked Boulanger to write a book on Csound in 1995. He had already written several tutorials and collected most of the elements that would accompany the book, but when he contemplated the task of authoring a complete guide to the complex software system, he knew he was going to need some help.

"I realized I could never be the ultimate expert in Csound," Boulanger says. "But thanks to Berklee sending me to international computer music conferences and giving me leave to teach in Eastern Europe, I befriended the best Csound teachers and composers from every corner of the world. I came back at MIT with a proposal. I said 'Here's the phase vocoder expert, let's get him to write that chapter. Here's the DSP expert, lets get him to write the DSP chapter.'"

Boulanger sent some 13,000 emails over a five-year period as part of his effort to gather and edit all the material. "It's a completely Internet book. It would have taken 10 more years if it wasn't written when it was."

More than 50 authors contributed to the 782-page book and accompanying two CD-ROMS. They contain more than 70 chapters, complete with example instruments and diagrams.

"It was brutally hard and very humbling," Boulanger says. "Berklee students helped me edit, design and work on the book. The book would not have happened without them and they deserve a great deal of credit." Fourteen students are thanked in the credits of the book and there are about 40 students whose music and instruments are featured in it.

The Csound book is a tremendously rich source of information on synthesis techniques, signal processing, composition and sound design. The CD-ROMs contain instrument libraries, tutorials, the Csound application, music written in Csound, user interfaces and reference materials; everything you need to get started and enough to keep you busy for years. And Boulanger has seen firsthand that, in the hands of enterprising Berklee students, CSound causes waves of musical innovation.

"Imagine what happens when really creative musicians find out how to work it," Boulanger says. "Give them this kind of a powerful tool and the sky is the limit. Art happens. Music happens. It's about creativity and Berklee is overloaded with creative individuals. Berklee students have a mix (of musical and technical knowledge) that scholars and professors from all around the world always comment on."

Boulanger has taught practically all subjects in Berklee's synthesis curriculum and stresses that the Csound class is an important step in understanding music synthesis.

"We're not just showing you how to turn on a box and find out what the menu options do," Boulanger says. "We're trying to help you develop integration skills so you know how to set up a studio and get all the components of a complex audio system working together well. Then you focus the students on an artistic level. How do you do production and innovative artistic stuff? Where Csound gets you is one step further to, 'How does it really work? I don't want to know how to use a reverb effectively or innovatively. I'd like to know, what is a reverb? How does a reverb reverberate?'"

And to take it one step beyond what Boulanger was talking about, how can I apply the concept of reverb in any way to any sound I choose? Csound goes beyond the level of commercial synthesizers where you twist knobs and tweak parameters to make new sounds. With new graphical options in Csound, you build the knobs, you decide what they do, how they work, and if you get in deep, you can understand right down to the bare bones, exactly what they are doing.

Just as a person can learn how a clock works by taking it apart, a CSound programmer in 2001 can replicate and refashion, if he wishes, the programs and instruments that Max Mathews created in the 1950s.

"With Csound you can go back and touch and learn from the very first things the great masters of our field did," Boulanger says.

Csound has been slowly working its way into music industry practice. Alumnus Tobias Enhus was recently hired by Los Angeles-based film composer and synthesist Jeff Rona to design a Csound library for Media Ventures. Enhus's instruments are featured in the Academy Award-winning film "Traffic." Recent graduate Jen Scaturro used Csound signal processing in a score for a nationally broadcast advertisement for VoiceStream cellular phones.

"Berklee students have always come at Csound fresh, asking 'How can I make interesting, compelling sounds?' or 'How can I use it professionally?'" Boulanger says. "It's opening a lot of doors for Berklee students in terms of graduate school, in terms of mainstream careers and I think it opens the mind and that's what's great about it."

Boulanger says Csound is also a common link between electronic musicians around the world. "It's everywhere. I got email from the Ural mountains (in Russia). I wasn't even sure that there was electricity there and they're asking me questions about Csound."

The work Boulanger and others have done with Csound continues. The Csound mailing list is an active forum where people at all levels of proficiency ask questions, share code and ideas and work to improve Csound and add new features as the field of sound synthesis advances.

At csounds.com you can download tutorials, videos, software, articles and much more. You can read the latest news on Csound, join the mailing list and find back issues of the Csound magazine. You can order the book, the instrument catalog and a CD of all-Csound music. In the future Boulanger is planning to organize a competition for Csound-based music, release more music CDs and continue to update the book and CD-ROMs.

"I feel like what I'm trying to do with my students in all my classes is share what a computer can do," Boulanger says. "'Look at what your computer can become with this, or look at what it can do with that. Look at what an unbelievably malleable canvas for your musical ideas this is.' The notebook computer is the instrument of the new millennium. There's the instrument to be a virtuoso on."