How you can use microtones in your own music, while still actually sounding like music
Table of Contents
- The three options for generating microtones
— 1a. How to choose a just intonation tuning
— 1b. How to choose an equal temperament
— 1c. How to choose an unequal temperament
2. Instruments designed to play microtones
3. Using microtones in a DAW (digital audio workstation)
4. Inspiration: Listening list of music with microtones
1. The three options for generating microtones
What is the overtone series?
Before we get into microtones themselves, there’s one fundamental concept you need to understand: the overtone series (also called the harmonic series).
When any physical object vibrates and produces a sound — a string, a column of air, a drum skin — it doesn’t just vibrate at one single frequency. It vibrates at a whole stack of frequencies simultaneously. The lowest one is the fundamental, which is the pitch you consciously hear as “the note.” But riding on top of it are a series of quieter, higher vibrations called overtones. These aren’t random. They follow a precise mathematical pattern: the 2nd partial is twice the frequency of the fundamental (one octave up), the 3rd partial is three times the frequency (an octave and a fifth up), the 4th is four times (two octaves up), the 5th is five times (two octaves plus a major third), and so on.
This matters enormously because our sense of musical consonance and dissonance is fundamentally rooted in the overtone series. When two notes sound consonant together, it’s largely because their overtones are closely aligned. When they clash, it’s because the overtones are colliding in ways our ears register as “roughness” or beating.
Most tuning systems in history — from ancient Greek modes, to the 12 notes of the modern piano, to tomorrow's microtonal experiments — is essentially an attempt to organize pitches in some relationship to this universal physical phenomenon. The three main approaches are: just intonation, equal temperament, and unequal temperament.
Just Intonation
Just Intonation means tuning your intervals to exact whole-number ratios derived directly from the overtone series. A perfect fifth is 3/2. A major third is 5/4. A harmonic seventh is 7/4. When intervals are tuned this way, the overtones of the two notes align perfectly, producing an almost eerily pure, beatless sound that equal temperament simply cannot replicate.
The upside is obvious: maximum consonance, a rich “locked-in” feeling when chords resolve, and access to harmonic colors that standard 12-tone equal temperament literally cannot produce (such as the 7-limit minor seventh, which is noticeably flatter and smoother than the minor seventh we’re used to).
The downside is equally real: every key is different. Modulating from one key to another in just intonation doesn’t just change the mood — it changes the actual interval sizes. Some keys will sound gorgeous; others will have “wolf intervals” that are painfully out of tune. And the complexity adds up fast. In a 12-note equal tempered scale, there are only 12 possible intervals between any two notes. In a 12-note just intonation scale, you can easily end up with 66 genuinely different interval sizes — each one a different ratio, each one requiring its own mental map to navigate.
Equal Temperaments (EDOs)
An equal temperament, or EDO (Equal Division of the Octave), solves the transposition problem by dividing the octave into a fixed number of equal-sized steps. Our familiar 12-tone equal temperament (12edo) divides the octave into 12 equal steps. The beauty of this is that every key is identical — if you know how to play in one key, you know how to play in all of them. There are a manageable number of distinct interval types to learn.
But the trade-off is that — apart from the octave itself — none of the other intervals are perfectly in tune. A 12edo perfect fifth is about 2 cents flat of the just 3/2 ratio, which is subtle enough that most ears accept it without complaint. The major third is 14 cents sharp of the just 5/4, which is more noticeable if you listen carefully. Most EDOs have some intervals that are a decent approximation of just ratios, and some that are nowhere close — awkward “dead weight” intervals that don’t correspond to anything natural in the overtone series, and can produce jarring dissonance if used carelessly.
The upside of exploring EDOs beyond 12 is that many of them approximate just ratios better than 12edo does, giving you new harmonic colors while still retaining the key-consistency benefit of equal temperament.
Unequal Temperaments
Unequal temperaments are a middle path. They don’t divide the octave into equal steps, so different keys have different characters — but unlike pure just intonation, they use a finite, manageable set of notes and avoid the most extreme wolf intervals by spreading the “tuning error” strategically across the scale.
The most famous historical examples are the various well temperaments used in the Baroque era (look up “well temperament” to go down that rabbit hole — it’s a fascinating piece of music history). In the modern day, the dominant form of unequal temperament in experimental music is the regular temperament, which we’ll discuss in section 1c.
A fourth option: NEJI (Near-Equal Just Intonation)
There’s also a more advanced technique worth briefly mentioning called NEJI — Near-Equal Just Intonation. The idea is to start with an EDO as your framework, but then slightly detune each step so that it aligns with an overtone of a very low “virtual fundamental” note. The result is something that sounds and behaves roughly like an EDO (consistent key structure, familiar interval relationships) but with a harmonic richness and “lock” that pure EDOs lack. It’s not a beginner topic, but if you’re curious, Zhea Erose on YouTube has excellent videos on it, and the Xenharmonic Wiki has a dedicated article.
1a. How to choose a just intonation tuning
So you want to explore just intonation, but you don’t want to spend three years mapping out a lattice of ratios before you can play a single song. Totally reasonable. Here are two approaches that give you a lot of consonant, musically useful harmony for a small number of notes — in other words, they’re efficient.
Combination Product Sets (CPS) are a family of just intonation scales constructed by multiplying together subsets of a small group of prime numbers. The most famous examples are the Hexany (6 notes), the Dekany (10 notes), and the Stellated Hexany (12 notes). These scales are loved by microtonalists because they pack an unusually high density of consonant chords into a small number of notes, and they have a kind of elegant symmetry that makes them feel coherent and navigable rather than arbitrary. A great place to explore them visually and aurally is the Gallery of Combination Product Sets on the Xenharmonic Wiki.
Overtone scales are even simpler to understand: you just take a series of consecutive harmonics from the overtone series and use those as your scale. For example, 12afdo (“12 arithmetically divided over…”) uses harmonics 16 through 32, giving you 12 notes that are literally drawn from nature’s own frequency ratios. The 16afdo is another popular choice. The Xenharmonic Wiki’s article on Overtone scales is the best place to explore these and hear what they sound like.
Both CPS scales and overtone scales share the same key advantage for beginners: they’re comprehensible. You’re not staring at an infinite lattice of possibilities. You have a defined set of notes, a clear set of consonant chords, and enough structure to actually write music — rather than just theorizing about it.
1b. How to choose an equal temperament
There are hundreds of possible EDOs, which can feel overwhelming. Here are the five friendliest starting points for musicians who are new to microtonality, plus some honourable mentions.
36edo is perhaps the gentlest possible introduction. Conceptually, it’s just 12edo with three “shades” of each note: the normal version, a “low” version (about a third of a semitone flat), and a “high” version (about a third of a semitone sharp). You can think of them as “red,” “blue,” and “purple” versions of your 12 regular notes if you want a visual metaphor. You already know how 12edo works — 36edo just adds texture and color to what you already know. It also has surprisingly good approximations of 11-limit harmony. See the Xenharmonic Wiki article on 36edo for details.
31edo is a beloved choice because most of your existing music theory knowledge still applies. Underneath 31edo’s expanded pitch set is the same meantone skeleton as 12edo — the familiar circle of fifths, the same major/minor key logic, the same chord vocabulary. The extra notes mostly give you access to harmonic 7th chords (those dreamy, bluesy four-note chords that are painfully out of tune in 12edo) and a much more accurate major third. If you want to bring your existing theoretical fluency with you into microtonal territory, 31edo is the most natural step.
22edo is the smallest EDO that approximates the basic just ratios better than 12edo does — meaning its fifths, thirds, and seventh harmonics are all closer to their ideal ratios than 12edo’s equivalents. It’s also practical: 22 notes is few enough to fit comfortably on a refreted guitar or a small keyboard layout. The catch is that 22edo has a very different internal logic from 12edo — the meantone skeleton is gone, and you need to develop new intuitions about how its intervals relate to each other. It’s a steeper learning curve, but a rewarding one. 22edo’s wiki page is a great starting point.
15edo is an interesting and somewhat unusual recommendation, because it requires some care with instrumentation. Its intervals don’t map cleanly onto standard Western harmonic logic, and the overtones of most acoustic and synthetic instruments can clash against its scale if you’re not paying attention to timbre. However, it makes up for that with remarkable efficiency: it packs an unusually rich set of 11-limit harmonic intervals (those beautifully strange quartertone-adjacent colors) into just 15 notes per octave. If you’re working primarily with synthesizers and you’re willing to choose your timbres carefully, 15edo offers a very distinctive sound world.
24edo (quarter-tone tuning) is often the first EDO people hear about, and its conceptual appeal is obvious: it’s just 12edo plus a note halfway between each of the existing 12 semitones. The notation even makes intuitive sense to anyone used to reading standard sheet music — you just add “half-sharp” and “half-flat” symbols. The bad news is that the quarter-tone intervals 24edo adds are among the more dissonant intervals in the microtonal toolkit: they’re not close to any simple just ratio, so using them harmonically requires a careful touch. A smart alternative is to use a 24-tone well temperament that keeps the familiar 12 notes in place but distributes the 12 additional notes more strategically, reducing dissonance where it matters most. A notable example is the Catler[24] scale, which is worth exploring if you find raw 24edo too harsh.
Honourable mentions: If none of the above appeals to you, 19edo (another meantone system, slightly different character from 31edo), 26edo, 27edo, 29edo, and 53edo (the classic “just intonation in disguise” option, beloved by theorists) are all worth investigating.
Non-octave equal tunings: There’s a small but fascinating category of equal temperaments that don’t divide the octave — they divide some other interval instead. These are genuinely experimental and not recommended as first steps, but if you’re feeling adventurous: the Bohlen-Pierce scale divides the tritave (a perfect twelfth, ratio 3/1) into 13 equal steps and has its own dedicated repertoire and community. Wendy Carlos’ scales — Alpha, Beta, and Gamma — divide a perfect fifth or other intervals into equal parts and produce some astonishingly alien but coherent harmonic landscapes.
1c. How to choose an unequal temperament
Unequal temperaments have a long history — well temperaments in particular were common across Europe from roughly 1680 to 1850, and many scholars believe that Bach’s Well-Tempered Clavier was written specifically to showcase how different keys had different “flavors” in the well temperaments of his time. Look up “well temperament” if you want a deeper dive into that history.
In contemporary microtonal music, the most widespread type of unequal temperament is the regular temperament. The concept was formalized and extensively catalogued by music theorist Paul Erlich in his freely available paper A Middle Path, which is highly recommended reading. It explains how regular temperaments are constructed — essentially, you take just intonation ratios and “temper out” (eliminate) certain small discrepancies between them to arrive at a simpler, more navigable system — and introduces most of the important ones.
Here are the regular temperaments most worth knowing about as a beginner:
For exploring 7-limit harmony (those rich, bluesy harmonics involving the 7th partial), Meantone[19] or Pajara[22] are excellent starting points. Meantone will feel familiar if you know Western tonal music; Pajara has a more exotic character with its distinctive “symmetrical” scale structure.
For exploring 11-limit harmony (including those quartertone-ish intervals that give microtonal music its most distinctive color), Miracle[21], Orwell[22], or Valentine[31] are all rewarding options. Each has its own interval logic and “personality,” so it’s worth listening to music written in each before committing.
Another strong choice — particularly for musicians who want a solid, well-mapped system with extensive learning resources rather than having to chart their own course — is John O’Sullivan’s Eagle 53 Temperament. O’Sullivan has written several detailed guides for musicians of various backgrounds who want to use Eagle 53, all of which are listed on his website at johnsmusic7.com. If you’re the type who works better with a clear map and a tour guide than with open wilderness, Eagle 53 is an unusually well-documented starting point.
2. Instruments designed to play microtones
The good news is that you may already have a microtonal instrument — you just don’t know it yet.
Fretless string instruments (violin, viola, cello, double bass, fretless bass guitar, oud, and many others) are inherently microtonal. There are no fixed frets to constrain you to 12edo; you can place your fingers anywhere along the string and produce any pitch you want. If you play a fretless instrument, microtonal music is already available to you — no modifications needed. Similarly, the human voice is a fully microtonal instrument. Singers naturally gravitate toward just intonation when singing in harmony a capella; the overtone series is quite literally built into how human hearing works.
For keyboard players, the gold standard microtonal controller is the Lumatone. It’s a hexagonal isomorphic keyboard with 280 individually illuminated, velocity-sensitive keys, each programmable to any pitch. The isomorphic layout is particularly powerful for microtonal music: because the same chord or scale shape appears identically in every key, you only have to learn interval patterns once — unlike a standard piano keyboard, where transposing means learning entirely new finger shapes. The Lumatone is a premium instrument at a premium price, but for serious microtonal keyboard work, it’s in a class of its own. Another great keyboard option is the Tonal Plexus from H-Pi Instruments, which takes a different physical approach but is equally capable and has a devoted community.
If you want to dip your toes into microtonal keyboard playing without spending anything at all, Scale Workshop is a free web app that turns your computer keyboard into an isomorphic microtonal keyboard. You can input any tuning, any scale, and start playing immediately in your browser. For the best experience, use a keyboard with “N-key rollover” (NKRO) — this allows all your keypresses to register simultaneously, so you can play full chords rather than being limited to two or three notes at a time.
For guitarists, Sala Muzik offers the gold standard in microtonal guitars: their adjustable microtonal guitars (designed in collaboration with Turkish guitarist Tolgahan Çoğulu) feature fully movable frets that slide in channels under each string, letting you configure any fretting scheme you want. You can set it up for 24edo quarter tones, for a maqam, for a specific just intonation scale, or anything else — and then reconfigure it for something entirely different when you’re ready. They offer classical, acoustic, and electric models. For bespoke handmade microtonal guitars with exceptional craftsmanship, JLJ Instruments builds custom microtonal guitars and replacement necks, with instruments in the hands of artists in twelve countries.
3. Using microtones in a DAW (digital audio workstation)
If you’re a producer or composer working in a DAW, microtonality used to be a painful, patch-it-together affair involving arcane MIDI routing hacks and plugin compatibility nightmares. That situation has improved dramatically.
The gold standard plugin for microtonal work in a DAW is Entonal Studio by Node Audio. MusicRadar called it “probably the most straightforward and comprehensive microtonal tool on the market,” and it’s hard to argue with that assessment. Entonal Studio works in two modes: as a MIDI effect (it processes notes and sends them to your existing instruments) or as a plugin host (it houses your existing VST/AU instruments inside itself and handles the retuning automatically, with no manual MIDI routing required). It comes with over 200 preset scales — from common EDOs and just intonation standards to Harry Partch’s 43-tone scale and Wendy Carlos’ Alpha/Beta/Gamma tunings — and has an intuitive radial graph interface for creating and editing your own scales. It supports Bitwig Studio, FL Studio, Studio One, and many other DAWs, with note names shared directly to the piano roll in those compatible hosts.
One important piece of advice: follow Entonal Studio’s documentation and recommended workflow rather than trying to wing it. Microtonal MIDI routing has some non-obvious technical requirements (particularly around multi-channel MIDI and MTS-ESP), and the difference between doing it properly and doing it haphazardly is the difference between all your notes playing in tune and half of them randomly snapping back to 12edo. The Entonal Studio website has clear setup guides — read them.
If for any reason Entonal Studio doesn’t fit your workflow, the Xenharmonic Wiki has two excellent resources: a List of Music Software covering every major microtonal tool, and a DAWs page with specific instructions for tinkerers who want to implement microtonality manually in their particular DAW of choice.
4. Inspiration: Listening list of music with microtones
The fastest way to develop your microtonal instincts is to hear what other people have already made with these tools. The good news is there is a lot of great microtonal music out there — and a lot of it sounds nothing like what you might expect from the words “experimental tuning.”
Budjarn Lambeth’s YouTube playlist Actually Good Microtonal Music is an excellent broad survey of microtonal music across many genres and many artists, with particular focus on experimental electronic music. His companion playlist 1 Great Track In Every EDO is especially useful for a learner: you can use it as a guided tour of what different equal temperaments actually sound and feel like in practice, rather than just reading about them in the abstract.
Once you want to go deeper, the Xenharmonic Wiki’s listening lists are extensive and carefully organized by tuning system, genre, and approach.
Listen first, theorize second. You’ll find that once you’ve heard a piece of music that moves you in an unfamiliar tuning, the abstract concepts snap into place in a way that no amount of reading about ratios and cents can quite achieve.
Happy exploring — the universe of pitch is much larger than twelve notes, and there’s genuinely beautiful music waiting for you in places most musicians have never thought to look.
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