At the Sounding Edge: OpenMusic and SuperCollider3
Even a casual glance at the contents of the linux-sound.org pages shows that Linux enjoys a broad range of interesting sound and music applications. Players, recorders and editors abound, and I plan to profile some of that software in this column. This month I present two applications that are rather close to the edge of Linux audio software development: IRCAM's OpenMusic and James McCartney's SuperCollider3.
OpenMusic (OM) for Linux is a porting project working to bring an outstanding music composition environment from Macintosh to Linux. As you might expect from a Mac music application, OM is an intensely graphic environment, and the developers at IRCAM (aka the Institut de Recherche et Coordination Acoustique/Musique in Paris) have done impressive work with the Linux version (Figure 1).
Figure 1. OpenMusic
Its Web site tells us that OM is a visual programming language based on CommonLisp/CLOS, that it is icon-oriented with a drag-and-drop GUI and that it has visual control structures for interfacing with the environment's Lisp structures. OM has been designed as a general-purpose programming language, but its unique classes and function libraries clearly are oriented towards the domain of music composition.
Non-musicians might wonder exactly what OM does for a composer. OM is not a software synthesizer, nor is it a soundfile editor or MIDI sequencer. OM's classes and functions supply the means for exploring the musical possibilities as the manipulation and permutation of sets for pitch, rhythm and dynamics, series and tone-row variation, random and aleatoric generative processes and many other techniques best carried out by a machine. In some respects OM is similar to Rick Taube's outstanding Common Music, another Lisp-based environment for music composition, but OM's rich GUI provides a very different experience.
This article is not intended to be an OM tutorial. I'm merely going to describe its basic operation and show off some of its interface amenities. I must stress that although OM itself is not a new program (the Linux port is for version 4.7.1), it is new to Linux and should be considered as beta-stage software. Not every aspect of the original has been imported faithfully, but I'm happy to say that most of the features found in the Mac versions have made it to the Linux port.
You can acquire OM from the IRCAM URL, but I seriously advise using the Planet CCRMA packages instead. OM requires some extra pieces you may not have on your system, including:
CMUCL, Carnegie-Mellon's version of Common Lisp
libgtk-canvas, a canvas object for GTK 1.2
CLG, the Common Lisp/GTK bindings
MIDIShare, a MIDI toolkit from the GRAME team
fluidsynth, a soundfont-based synthesizer
Specific versions of these dependencies may be required, so check with the OM Web site for a list of the most current requirements. The Web site also includes detailed installation and configuration instructions from IRCAM developer Francois Dechelle. I repeat, however, that you're probably better off with the Planet CCRMA packages. DEB packages for the AGNULA Linux audio distribution should be available soon.
Once everything has been installed and correctly configured, you can launch an OM session with the following series of commands:
fluidsynth -a alsa -m midishare soundfonts/8mbgmsfx.sf2 msconnect omlinux
I suggest opening each program from its own xterm. Doing so makes it easier to keep track of any reports or error messages coming from the specific app.
On my 800MHz machine, OM takes a little time to open. Lisp is an interpreted language, so it takes a while for everything to prepare. When the system is ready for use the GTK canvas object appears, and you're ready to start using OM.
OM is similar to its IRCAM synthesis sibling jMax in its use of icons to represent its various classes and libraries. These icons are placed on the canvas and wired together to create a patch. An OM patch may be a note generator, a MIDI event processor or even a simple playback device. OM's icons include classes and functions for arithmetic, list manipulation, random number generation, various MIDI actions, program control and many others. Abstraction (that is, a patch within a patch) is supported, and patches may be saved for reuse within other projects.
Figure 1 shows off a relatively complex OM patch from Karim Haddad's series of helpful tutorials. In this patch (Tutorial 14) we can see many of OM's main features at work. Various icons have been connected to form a MIDI note generator that directs its output to a pair of General MIDI programs played on two MIDI channels by way of the fluidsynth synthesizer. The big blue-green object at the bottom of the patch is an instance of a music/score class called a CHORD-SEQ. In true Lisp fashion, once the patch has been built, it must be evaluated before playing by selecting it and then typing v on the QWERTY keyboard. Type p to hear the results and s to stop the playback. Reevaluating the object produces a new note series.
The example also demonstrates OM's abstraction at work. Both the omloop and note generator icons are subpatches, and I have opened them up for inspection in Figure 1. Again I'll skip the details of subpatch construction, but I should note that subpatches are built in the same way as the way I have described for patches.
Similis sum folio de quo ludunt venti.