Just Intonation

Why discuss this topic? All Drums and Drones electroacoustic pieces are composed in adherence to the Just Intonation tuning system. All Drums and Drones acoustic pieces are constructed on the principles of Just Intonation though embrace elements outside of the system. 

What is Just Intonation? It is a tuning system based on the naturally occurring acoustic phenomenon known as the harmonic series. What are harmonics? Harmonics are ‘building blocks’ of sound, kind of like a ‘sonic DNA’; these ‘building blocks’ function as individual pieces of a larger whole, in a similar way as most buildings are built of many pieces. For example, the tone of a person’s voice is actually a complex composite of many tones rather than just one. Harmonics come in two types: the fundamental and the overtones. There is only one fundamental; it is the lowest in pitch and often the most prominent. All of the other subsidiary pitches are the overtones; they are relatively quieter and higher in pitch. A key role of overtones is to help in differentiating and determining the unique characteristics of overall ‘sound-identity.’

How are harmonics related to the Just Intonation tuning system? A tuning system is a structure for defining the intervalic distance between pitches – a relative ‘highness’ or ‘lowness’ of sound. Regarding harmonics and the infinite number in which they exist, their interrelationship is defined according to the aforementioned harmonic series. This series can be thought of as a type of musical scale: it’s structure – the order of its pitches – follows a pattern in the same way a musical scale follows a pattern. The structural pattern of the harmonic series is what forms the basis for Just Intonation, or “nature’s tuning system” as it is commonly known. A cool aspect of the sequence and structure of the harmonic series is that it is universal, it is always the same; the only way the harmonic series expresses ‘difference’ or change is through the relative volume levels of the various overtones along its sequence. (As a side note, the intonation of Just Intonation – the spacing of its pitches – is very different than that of 12-tone equal temperament, the tuning system that is the best for almost all contemporary ‘Westernized’ musics.)

What is the structure of Just Intonation? The pitches in a Just Intonation ‘scale’ are all theoretically derived from a single root pitch, a.k.a. the fundamental. By dividing the fundamental into equal parts, the subsidiary tones, a.k.a. the overtones, are revealed. For example, if a string is divided in half it then becomes two parts in relation to the whole; this can be expressed by the ratio 2:1. Each half will vibrate twice as fast and sound twice as high as the whole, a.k.a. the fundamental; this 2:1 ratio is commonly known as an “octave.” If the string is divided into three equal parts – expressed by the ratio 3:1 – then each third will vibrate three times as a fast and sound three times as high as the fundamental. With each new division of the fundamental a new pitch is yielded. With this theoretical method, all of the pitches of a Just Intonation scale exist in whole number interrelationships and consequently vibrate together in pure cyclical ratios. (In contrast, the relationship between pitches in 12-tone equal temperament exist in non-whole number relationships since they are based on the irrational ratio of the twelfth root of two).

Why should I care? Just Intonation treats sound waves as the physical objects that they are – though sound waves aren’t seen, they are heard and felt; its origins are in the innate natural physics of sound and it organizes its methods according to these ‘given’ acoustical properties. Central to Just Intonation is the premise that from one fundamental an endless infinity of possible overtones can be derived; this process occurs from the whole number divisions of the fundamental, i.e. 2:1, 3:1, 4:1, etc. Conversely, all overtones exist as derivations of the fundamental and hence are expressions of a singular source, the fundamental. When sound waves resonate together in this way, their cyclical vibrations are symbiotically ‘in tune’/in phase and accordingly reinforce their structural relationship: that each pitch (i.e. an overtone) is derived from and refers back to a singular point of origin (i.e. the fundamental). At this point the physical power of sound ‘unlocks’ to both suggest and impart an infinitely expanding psychoacoustic awareness. Just Intonation is a key to this lock. 

Guitar innovator and music theorist Jon Catler demonstrating basic principles of Just Intonation:


*Just Intonation is a vast topic and can be a ‘slippery’ concept to describe. Each enthusiast of the system may have a different area of interest in regards to it, or preference for mode of explanation. Some of these various modes may overlap and some may not. The exposition that I present is meant to cover core principles and also serve as an offering in the ways it appeals personally and how it functions in the compositions of Drums and Drones.