Conventional wisdom sometimes teaches that only two kinds of thing happen: things we can predict and describe perfectly with an equation, and things we can't. This simplification is written into the worldview we inherit from the Greek Mathematician Philosophers, that the world is an imperfect implementation of perfect forms. It even governs our art: we start by drawing 'perfect' geometric primitives, straight lines, rectangles, circles, even though these are nowhere to be found in nature.

However, if we look closer, we find that sometimes 'predictability' is not a function of 'description'. Some systems can be perfectly described, but completely unpredictable. Other systems, only probabilistically described, can still exhibit quite patterned behaviour. Still others can offer different levels of predictability depending on the time frames over which they are observed.

Why is this interesting to composers? Because the atoms of music operate on similar patterns of novelty and repetition. Strong musical structures, be they at the level of phrase, melody, or section, rely on the balance of repetition and change. Complex results emerge from the combination of simple building blocks. And, as every composer knows, inspiration always comes from the outside.

The constant, un-patterned variation of a random pitch generator is only musically interesting for a very short period of time, after which the lack of recognisable self-reference disengages the listener. By contrast, the constant, obsessively patterned repetition of a looped hook offers no developmental novelty. Both are forms of stasis, merely observed on different time frames.

What is interesting are systems which generate the kinds of behaviours which musicians compose into their music: melody which 'refers to itself' by repetition with change, contour with varying fine and gross structure, rhythmic cycles balanced with excursion and extemporisation.

Stochastic processes (dealing with controlled probability) and Chaotic processes (dealing with emergent patterns) offer two complementary methods of exploiting these features. However, all too often with these systems there is the temptation for the performer to 'hand over to the system' and assume the role too readily of passive audience member.

Stochastic Instruments aims to create Eurorack modules which exploit these systems as 'creativity pumps' but without abandoning the essential element of musical performance. Music has existed as a group human activity for at least 60,000 years: instruments are to be played and explored not merely set into motion. We aim to find the balance between the long tradition of performative practice in music while embracing the systems and process aesthetic of the 1960s Experimentalists that informs so much of Eurorack composition, whatever the surface form of the music.

We hope you enjoy playing these modules as much as we do.

© Stochastic Instruments Ltd. 2021