1 Introduction
Most of my flâneries concern some aspect of functional programming. This one is different. It explores ideas used in the synthesis of sound for musical purposes. Some aspects of this topic remind me of functional programming, notably the use of small, powerful functional units that can be used for multiple purposes and combined in new and surprising ways. Other aspects seem antithetical to the abstraction and careful interface control that is a hallmark of functional programming. In particular, the use of patch cables to carry signals between two arbitrary points is more reminiscent of the "spaghetti programming" common in assembly-language code or early FORTRAN with its GOTO statements. The stock image of a synthesizer with a tangle of patch cables obscuring its front panel even looks like a mess of spaghetti! But even if the connections are not elegant, the underlying design principles often are.
The first synthesizers were modular in nature, created contemporaneously by Robert Moog on the east coast of the United States and Don Buchla on the west coast, in the early 1960’s. They were used by both popular musicians and more serious composers. But they were expensive (custom-built for those who could afford it) and impractical for performance use (since they could not be quickly reconfigured). Manufacturers subsequently developed fixed-architecture synthesizers, which were less flexible but often more portable, and allowed storing and quick recall of preset configurations. Keyboards were built in or could be plugged in, and a standardized protocol for exchange of musical information (MIDI) was developed.
Modular synthesizers continued to be produced, but became a more specialized and obscure niche, until Dieter Doepfer in Germany, in 1995, created a smaller, more affordable, standardized format that came to be known as Eurorack. Other manufacturers (sometimes just one or two people taking advantage of the ability to outsource the creation of printed circuit boards) created compatible modules, and today there are thousands of modules from hundreds of manufacturers available. While fixed-architecture synthesizers continue to dominate the market (with some truly amazing bargains to be had), there is a thriving community of Eurorack users.
In the spirit of my other flâneries, I would like to start by explaining some basic principles of modular synthesis with reference to a single elegant and powerful multi-function module. I will then describe the other modules I have chosen to purchase and use, to give you a sense of a complete system and its design principles.
There are many social media videos, blog posts, and forum posts that will advise you on how to put together your own modular system. Some of these people are trying to sell product or garner views or clicks; others might be validating their own choices. Even the best-intentioned of such efforts are necessarily generic. If you are considering a modular system, there is no substitute for your own individual research, due to the amount of choice possible. Your own personal design will depend on what kind of sounds you wish to make, how much money you wish to spend (or, perhaps more accurately, the rate at which you can spend), what other equipment you have or are contemplating, and your own abilities and desires.
My intention is to be informative and descriptive, to provide a basis for such personal research. I’m sure I can’t resist offering advice, but it should not be taken as authoritative.