Designing Audio Objects for Max/MSP and Pd by Eric Lyon (review)

Eric Lyon’s Designing Audio Objects for Max/MSP and Pd is a superbly executed addition to the growing body of texts concerning sophisticated computer programming techniques for electronic musicians. The text explores techniques for the creation of audio objects (externals) in the C programming language for the data-flow programs Max/MSP and Pure Data (Pd). External audio objects offer a means to enhance and extend the options provided by the core libraries of Max/MSP and Pd. Learning how to create and utilize them empowers the reach of the electronic musician, opening up numerous creative possibilities. Creating one’s own custom audio objects provides the musician with the opportunity to devote programming time only to the task that is of immediate interest, such as designing a specialized audio processing tool like a flanger, without having to be overly concerned with the details of the programming environment within which it is operating.

The basic attraction of working with audio objects lies in the fact that these modular pieces of code can be loaded upon demand into the host program. Once the basic functioning of the digital signal processing (DSP) is implemented, the user can interact with the new audio object in a variety of ways, and place it within the context of other objects. Furthermore, these objects can make use of all of the audio capabilities of the host program. Creating specific audio objects for signal-processing tasks is often less cumbersome and more efficient than using a sub-patch, an abstraction, or a collection of native objects to do the same thing. There is a compactness and elegance in the use of such purpose-built externals, and over time the dedicated composer can develop and refine a collection of tools that personalize not only working methods but also the available sound palette for creative composing. Utilizing the comprehensive framework of Max and Pd, the programmer can focus on the problem at hand—the algorithm itself—rather than the details that would allow the algorithm to work in real time. Audio plug-ins typically require some sort of specific interface, or a runtime environment would have to be created, in order to utilize them. The context for programming audio objects in Max and Pd avoids this requirement, however, and is therefore much more inviting for the electronic musician. The open-ended, modular nature of Max and Pd allows for user-designed audio objects to function in many different ways and in imaginative combinations.

Max/MSP and Pd are established standards in the electronic music field, and both their utility and their user base continue to grow impressively. The integration of Max/MSP into Ableton Live and the encapsulation of programs such as Csound and RTCmix into Max and Pd are indications of the broadening appeal of these tools for electronic musicians working in numerous musical genres. Owing to this expanding interest there are a number of good texts appearing that deal with the issues of sound design, synthesis techniques, and musical signal-processing options provided by the programs. There is a need, however, for a text that deals explicitly with the creation of external audio objects; their design, programming, debugging, and integration; and the C programming and DSP skills required. Lyon’s book admirably fills this void and presents a highly cogent discussion of the various factors involved.

Presently, there are hundreds of audio objects for Max. Programmers outside of the primary development community are increasingly creating these objects. In a sense, Lyon’s book is written for these kinds of programmers—serious electronic musicians who want to expand the utility of Max/MSP and Pd in creative and idiosyncratic ways. One worthwhile side benefit...