Choosing a tuning to write microtonal jazz music with

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 If you're making your first microtonal jazz album — these are some tunings that play nicely with jazz

So you’ve heard microtonal jazz — that strange, addictive music that seems to find new emotional colours you didn’t know existed — and you want to make some yourself. But now comes the first big question: which tuning do you use?

We’re going to walk through a range of options, from the simple to the deep end of the pool, and give you a practical sense of what each one offers.

But first, let’s talk about what we actually need from a microtonal jazz tuning — because not all tunings are equal for this purpose, and the criteria are different from what you might expect.

What makes a good microtonal jazz tuning?

1. Efficiency — few wolf intervals

The most important thing is that the tuning is efficient. In microtonal theory, a “wolf interval” is an interval that’s too out-of-tune to be usable. Every tuning system has some wolves, but you want as few as possible.

Why does this matter so much for jazz specifically? Because jazz is built on improvisation, and improvisation is built on freedom. If you’re constantly having to mentally dodge landmines — notes that will produce a horrible clash no matter what you do with them — your playing will be cramped and timid. You need a tuning where, no matter where you land, you can build something consonant on top of it. Efficiency is freedom.

2. New consonant colours — 7- and 11-limit intervals

The whole point of going microtonal in jazz is to add new harmonic colours, especially new upper chord extensions. The most valuable new colours come from the 7-limit and 11-limit — these are the lowest harmonics that don’t already exist in 12-tone equal temperament.

Key intervals to listen for:

  • The harmonic seventh (7/4) — a gorgeous, soft seventh that sits between a minor seventh and a major seventh
  • The neutral seventh (11/6) — halfway between a minor and major seventh, floaty and unresolved
  • The neutral ninth (11/5) — similarly ambiguous and dreamy
  • The subminor tenth (7/3) — a lower, darker minor tenth
  • The neutral eleventh (11/4) — a haunting, suspended eleventh

A good microtonal jazz tuning should approximate these closely enough that they sound smooth and consonant, not buzzy or clashing.

3. Good 5-limit harmony — your familiar thirds and sixths

You also need the 5-limit consonances to be in good shape. These are the backbone of standard jazz harmony: the minor third (6/5), the major third (5/4), the minor sixth (8/5), and the major sixth (5/3). These intervals need to be available and sound right, so that all your familiar jazz vocabulary still works alongside the new microtonal colours.

4. Passable — but not necessarily perfect — fifths and fourths

Here’s where jazz differs from many other genres that go microtonal. The perfect fifth (3/2) and perfect fourth (4/3) — 3-limit intervals — don’t need to be razor-accurate the way they do in, say, metal, where the power chord is everything. A fifth that’s off by 15 cents would still be a problem in jazz. But something like 10 cents flat or sharp? Passable. Jazz harmony leans on thirds, sevenths, and extensions far more than it leans on bare fifths.

5. A circle of fifths — non-negotiable

However — and this is critical — the tuning needs to have a circle of fifths. Not because the fifths need to be perfect, but because jazz harmony moves around the circle of fifths. The ii-V-I progression. The cycle of dominant chords. The rhythm changes bridge. All of this is built on the assumption that you can travel around the circle and eventually come back home. A tuning where the fifths spiral off into infinity and never close is a tuning where a huge chunk of the jazz language simply breaks.

With those criteria in mind, let’s look at some tunings.

The tunings, from simple to complex

19edo — the best starting point for microtonal jazz

19edo divides the octave into 19 equal steps. It’s the most natural first step into microtonal jazz for a few reasons.

First, it’s efficient. There aren’t many wolf intervals. You can roam freely.

Second, it has a circle of fifths — 19 of them, not 12, but the harmonic logic of moving around the circle feels familiar because 19edo is a meantone tuning, just like 12edo. Same family, different member. Your ii-V-I progressions still work. Your ears will orient quickly.

Third, while the 7- and 11-limit intervals in 19edo aren’t stunning — they’re not as accurate as some of the deeper options on this list — they’re miles ahead of 12edo, where these intervals essentially don’t exist at all. It’s a genuine upgrade in harmonic colour.

The 19-key circle might feel like a lot to wrap your head around at first, but give it a few weeks and it clicks. Start here.

Not 24edo — but Catler[24] or Catnip[24]

24edo (quarter-tone tuning) is the most commonly discussed alternative to 12edo, but it’s actually one of the weakest options for jazz. The intervals it adds — the quarter tones that sit exactly between your familiar notes — are mostly dissonances. Improvising in 24edo is like being handed a spice rack where most of the jars contain things that taste awful. Theoretically interesting. Practically difficult.

Instead, consider Catler[24] or Catnip[24]. Both are 24-note scales, but instead of offsetting two copies of 12edo by 50 cents (quarter tones), you offset them by about 25 cents (Catler) or 35 cents (Catnip). This small change makes an enormous difference: suddenly those in-between notes approximate a whole range of beautiful 7- and 11-limit consonances rather than ugly dissonances.

The other big advantage: you still have two complete, intact copies of 12edo inside the scale. All your existing music theory knowledge applies without modification. You don’t need to unlearn anything. If you’re playing with another musician, you don’t need specialised instruments — just tune any two regular 12-tone instruments 25 (or 35) cents apart. Done.

Harmonically, you can think of it as having two parallel circles of fifths — two parallel universes of key centres — with cleverly placed “teleportation portals” between them that let you modulate from one universe to the other and back. It’s jazz harmony, but with a parallel dimension.

Dreamtone[12] and Oceanfront[12]

These two scales are for a specific kind of player: someone who loves the melodic logic of 12-tone scales but wants to throw out the harmonic content entirely and replace it with something alien.

Both scales preserve the melodic shape of 12edo — the circle of fifths is intact, the number of notes is the same, the scale patterns feel the same under your fingers — but the harmonic content is completely replaced with strange xenharmonicintervals.

Because these are highly unequal scales, every key centre sounds dramatically different from every other. This is a feature, not a bug: part of the expressive palette is moving between key centres to access different emotional textures.

The distinction between the two: Dreamtone sounds earthy, dusty, and ancient — think desert sand and old wood. Oceanfront (also known as Ultrapyth) sounds watery and metallic — think tidal pools and cyberpunk cities. Neither is a Swiss-army-knife tuning capable of a wide emotional range, but within their niche, each is remarkable.

Eagle 53 — the well-documented option

Eagle 53 is an unequal 12-tone scale created by John O’Sullivan, who has written extensive guides on using it on his website at johnsmusic7.com. If you like reading documentation and working through a structured system, this might appeal to you.

Like Dreamtone and Oceanfront, Eagle 53 keeps the 12 note names you know — but the notes are no longer equal-tempered. Some key centres have rich 7- and 11-limit colour; others are more familiar. The circle of fifths works exactly like it does in standard 12-tone tuning — that part is easy. What’s hard is learning the individual character of each of the 12 key centres and how to use them expressively.

The extensive documentation makes Eagle 53 one of the more accessible “advanced” options on this list.

22edo — accurate harmonics, kooky fifths

22edo is a fascinating and powerful tuning. Its 7- and 11-limit intervals are strikingly accurate — among the best on this list. Its 5-limit thirds are slightly softer than you might be used to but not out of tune. Wolf intervals are relatively sparse.

The catch: 22edo is a superpyth tuning, not a meantone tuning. This means the circle of fifths behaves in ways that feel strange if you come from 12edo. The logic is still there — there is a circle, and it does cycle through all 22 key centres — but the harmonic relationships are shifted in ways that require real adjustment time.

Once you’ve adjusted, 22edo is a remarkably expressive tool. But budget for that learning curve.

Magic[22] — for the deep diver

Magic[22] is a 22-note unequal scale that shares some structural DNA with the 22 śrutis of Indian classical music theory. Like the śrutis, it’s a highly efficient packing of the most consonant intervals — familiar and microtonal — into 22 notes, with relatively few wolves.

The major caveat: there is no familiar circle of fifths. Magic[22] does have excellent fifths — among the best — but they don’t form a closed cycle. Instead, there’s a “circle of major thirds” that cycles through all 22 key centres and serves the same structural role that the circle of fifths plays in standard jazz. Learning to think harmonically in terms of this circle of major thirds is the core challenge.

If you’re drawn to this scale, active listening to traditional Hindustani and Carnatic classical music is highly recommended. It will build your intuition for navigating these interval spaces in ways that words and theory alone cannot. If lessons from a Carnatic or Hindustani music educator are accessible to you, even better — not essential, but a genuine fast-track.

31edo — the high-investment, high-reward option

31edo has more accurate 3-, 5-, 7-, and 11-limit intervals than almost any other tuning on this list. Its harmony is extraordinarily rich and vibrant. It’s been used by adventurous musicians for centuries — Huygens wrote about it in the 1600s.

The problem is wolf intervals. 31edo has more of them than most of the other options here, which puts pressure on the improviser: you have to know your way around the tuning well enough to navigate around the wolves. That takes time.

On top of that, the circle of fifths has 31 key centres. Meantone logic still applies, so it’s the same logic as 12edo, but 31 keys is a lot to internalise.

31edo is the highest-investment option with some of the highest rewards. If 31edo’s fifths feel slightly too shaky for your taste — or if you find its sharp tritone a bit grating — try the Meantone[31] scale drawn from 43edo instead. This gives you effectively the same scale but with stronger fifths and a smoother tritone, at a slight cost to the accuracy of the thirds and sevenths (but still better than 12edo’s thirds and sevenths).

37edo — the bizarre wildcard

37edo is the oddball on this list and it earns that title.

Most EDOs have one size of fifth, and then wolf intervals that are just-slightly-too-wide or just-slightly-too-narrow. 37edo has two sizes of fifth — both of them marginal, neither truly ideal, but both passable. The strange result of this is that wolves are surprisingly rare for a tuning of this size: instead of one good fifth plus two nearby wolves, you have two acceptable fifths and fewer wolves.

The 5-, 7-, and 11-limit extensions in 37edo are comparably excellent to 31edo. The truly mind-bending thing is what happens with the circle of fifths: there are two of them, each cycling through all 37 key centres but in a different order. This is deeply strange. It’s also, in the hands of someone who masters it, a tool for the most unexpected and yet somehow-logical modulations you’ve ever heard.

37edo has a steep learning curve. But if you’re the kind of musician who is energised rather than scared by “steep learning curve,” this one might be calling your name.

9edo, 10edo, 15edo, and 16edo — the gamelan options

These small tunings are a special case. 9edo, 10edo, 15edo, and 16edo each offer a lot of useful new chord extensions in a very small number of notes, and their circles of fifths are small and easy to memorise. In those ways, they’re simpler than anything else on this list.

The challenge is that their fourths and fifths are far enough from just that they sound genuinely out of tune on most instruments. This isn’t automatically a dealbreaker, but it does mean that instrument choice is critical. Pitched percussion — metallophones in particular — often gel beautifully with these tunings in a way that strings or brass do not. Sine wave and triangle wave synth patches work well. Reverb and tremolo are your friends.

The reference point here is gamelan music: 10edo and 15edo contain rough approximations of the slendro scale, while 9edo and 16edo approximate pelog. Listening deeply to Javanese and Balinese gamelan music will give you an intuitive map for navigating these tunings far faster than any amount of theory reading.

Just intonation scales — for the harmony maximalist

If your primary interest is in packing the maximum possible harmonic richness into your music — and you’re willing to let go of the circle of fifths entirely — just intonation scales are worth exploring.

Some strong options:

None of these have anything resembling a circle of fifths, so you’ll be building a new system for navigating jazz harmony largely from scratch. That is a significant undertaking. But the harmonic rewards — the sheer density and beauty of the consonances on offer — are unmatched.

Where to start

If you take one thing from this article, make it this: start with 19edo, Catler[24], or Catnip[24].

All three are accessible, efficient, and rich in new harmonic colour. All three have a workable circle of fifths. All three will give you a genuine taste of what microtonal jazz can sound like without requiring you to rebuild your entire musical understanding from scratch.

If you dive in and find that these tunings feel right, stick with them — there’s no rule that says you have to keep going “deeper”. Many excellent microtonal jazz musicians work primarily in 19edo or a two-keyboard offset system and have no desire to go further.

If those tunings don’t quite so it for you, though, then you have a whole menu above to explore. The more complex you go, the more you’ll need to invest in learning — but every tuning on this list has something genuinely beautiful to offer.

Good luck. May your wolf intervals be few and your upper extensions be lush.

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