# Are there regular open tunings for guitar?

I understand the difference between open tuning (all 6 open strings play a chord) and regular tuning (the intervals between strings are the same). I would like to know if it is possible to have both, that is, a tuning with equal intervals between strings that when played open gives a major or minor chord. Is this actually possible?

• 1) "regular tuning (the intervals between strings are the same)" No they're not [they nearly are, but not quite]. 2) How do you imagine this could work, as the intervals that make up a simple major or minor triad are themselves not regular? Commented Sep 13, 2021 at 15:30
• Perhaps not so outlandish of a question, if a bit mathematical in nature. For example, a regular open tuning does exist for augmented triads! Major and minor, though, are not possible. Commented Sep 13, 2021 at 20:26
• @AlfredoCareaga Stack 5 major thirds on top of any starting note, and you'll find one. Commented Sep 13, 2021 at 23:22
• this is a bit microtonal, but i am curious what it would sound like if you made all the intervals three and a half semitones Commented Sep 15, 2021 at 5:18
• you could open-tune to a minor chord and just make the thirds major if needed using one or two fingers? Use barre technique plus a finger or two to get major Commented Sep 17, 2021 at 9:27

Is [...open tuning...the intervals between strings are the same...when played open gives a major or minor chord...] actually possible?

Categorically, no.

In terms of "stacked" intervals major and minor triads are not "regular" interval stacks. Those chords alternate major and minor thirds. Additionally when the chord root is repeated at the octave it will be a perfect fourth above the chordal fifth. So, that's three different interval types involved in the stack to build major and minor triads.

If you stacked only major thirds for an open tuning, the resulting chord would be an augmented triad.

If you stacked only minor thirds for an open tuning, the resulting chord would be a fully diminished seventh chord.

If you stacked only perfect fourths for an open tuning, you would have six of the seven tones to get a complete diatonic set. Arranged as all perfect fourths you might call it a very large quartal chord, but those chords tend to be only 3 or 4 perfect fourths stacked up not six.

Of course just because those tunings don't form either a major or minor triad does not mean you can't use them. An interesting thing about alternate tunings is there are some that are very common, like "drop D" or "open G", but you can make up any tuning you want.

Regular tuning gives P4 between all strings except 3rd-2nd, which is M3.

Basic major chords are made up from M3, m3 and P4, while minor chord are similar, but m3, M3 and P4.

Thus the answer is no, as there can't be a mix between regular/major or regular/minor. There could be say, bottom 3 give major, top three minor, but then you've lost the regular tuning.

Any alternative tuning will mean having to use different fingering anyway, but using a 'Spider Capo' may give some inroads to what you're after.

• If you tune a guitar from C in P5’s you’ll get a Cmaj13 chord (!) C G D A E B Commented Sep 13, 2021 at 18:01
• @JohnBelzaguy Very clever, but a more typical voicing of Cmaj13 would omit the G 😉 Commented Sep 14, 2021 at 9:59
• @IanGoldby …and probably the C too! Actually I like having the 5th in maj7 9 13 chords. Commented Sep 14, 2021 at 20:35

This is probably not what you are looking for, but:

If you have the same diatonic interval (e.g. a third or a sixth), you could have a "regular" tuning that gives open triads. Say we pick the key of G:

• Thirds: C - E - G - B - D - F♯ – Contains both C major, G major, E minor and B minor triads.
• Sixths: F♯ - D - B - G - E - C – Contains the same, but inverted (and probably not in a musically useful way).

In either case, you won't get a full chord across all the strings. You have to play a 3-adjacent-string subset only. If you have a 3-string instrument, it does fit the definition.

If you build a regular tuning with seconds, fourths, fifths, or sevenths, you can also get the notes of major and minor triads, but the notes to form them will not be on adjacent strings.

Another thought: You did say "a major or minor chord". You could make a 3-string instrument with a neutral third of about 350¢ between strings. Depending on context, that might be heard as "major or minor", though it's probably more correctly described as "neither major nor minor".

• Why do you consider the all sixths tuning to be less useful? The span of 2.5 octaves might be actually more practical than 1.5 octave in the all third tuning. Commented Sep 13, 2021 at 20:25
• @user1079505 One problem is the pitch range is absurd for that tuning. If my math is right, then a low F#1 bass string would still require the guitar to have a C5 for its high string - I'm counting 3.5 octaves (rather than 2.5), and that excludes the entire fretboard! Also, close-position triads are hard with massive intervals between strings, and a lot of music uses those frequently. Commented Sep 13, 2021 at 20:33
• @user1079505 In the sixths tuning, none of the triads is in root position while the thirds tuning has them all in root position. Commented Sep 13, 2021 at 20:53
• @user45266 Oh right, it's 3.5 octaves, quite a lot. But regarding close voicings, those are used on guitar often because it's difficult to play open voicings in standard tuning. But yes, after thinking more about it, all sixths seems quite extreme. Commented Sep 13, 2021 at 21:26

;tldr: You can't get major or minor chords in a tuning where all intervals between consecutive strings are the same, but you CAN get other nice sounds.

As previous answers have pointed out, getting all the open strings to sound a major or minor chord while keeping the intervals between strings the same is impossible.

The intervals between consecutive notes in a major or minor chord which extends over several octaves are minor thirds, major thirds and fourths; 3, 4 and 5 semitones, respectively; and you need all three of them to make the chord. You could try to get around this by imagining larger intervals between consecutive strings, like an octave + a third, but it turns out you still need three different intervals to get complete chords.

To put it simply, what you ask for is impossible.

Others have pointed out that some intervals can be stacked to make chords other than major or minor chords. The most obvious one would be the diminished and augmented chords, made from all-through minor thirds and major thirds, respectively. This can work, but they do contain notes outside your desired major and minor chords. More importantly, these chords are not ones that are comfortable to listen to when you strum them for a long time. I thus think they sort of miss the point of an open tuning!

BUT!

There is a way (in theory two ways!) to tune you guitar in a completely regular way which allows for pleasant open chords!

There are two intervals that can be stacked indefinitely and still make good sounding chords: The unison and the octave!

Tuning all notes to the same note makes it very regular, and all notes work well together. In fact, all notes are part of the same major or minor chords, and this is the best you can hope for. I'd definitely say it's an open tuning.

To achieve unison tuning, you could simply restring the guitar to have only one type of string, e.g. only A strings. This can be quite a cool effect, like a chorus, and it can bring out overtones in interesting ways. To get an idea, have a look at so-called monochords (e.g. this one from Thomann). The clips at the site is quite nice actually, and more clips can be found if you check out their other monochords.

If you're tuning all strings an octave apart you'd definitely need to change strings. I'm quite sure you can't actually find such a range of strings, but just maybe if you look around among strings for various instruments and get really creative. It would be fun to see someone do this if it's possible.

You could also cheat a bit and mix among unisons and octaves. The patterns to play chords would be the same as for either of the other two types, and it would still sound cool. It's not even totally unheard of, and something sort of like it was famously used on the song Iris by the Goo Goo Dolls. (Though I think they cheat even more and have one string tuned to a different note..)

• Ah yes, the ostrich tunings! Creative, but doesn't quite work since OP asked for a chord that "played open gives a major or minor chord". Alas, one pitch class in isolation isn't a major or minor chord. Commented Sep 13, 2021 at 23:27
• I feel like the world hasn't experimented enough with a dim7 tuning... Commented Sep 14, 2021 at 0:16
• @AndyBonner: I use G-D-d-f-g#-b all the time (fifth string is the lowest) and will gladly extoll its virtues to anyone who cares to listen. The minor-thirds pattern only holds for the top four strings, but playing major, minor, diminished, or augmented triads in any inversion, as well as many flavors of seventh chords, is insanely easy, and the fifth and sixth strings make it easy to add a suitable bass note for most of them. Commented Sep 14, 2021 at 3:44
• @user45266 Oh, I see. You are right. I wrote this too late in the night... I'll edit the post to account for this. Commented Sep 14, 2021 at 9:26

Augmented and diminished tunings are regular and form major or minor chords, E2 G#2 C3 E3 G#3 C4 or E2 G2 Bb2 Db3 E3 G3.

• Neither of those tunings contains a complete major or minor chord. Commented Sep 14, 2021 at 4:20
• if you insist a chord isn't a chord without a perfect fifth... Commented Sep 14, 2021 at 4:27
• Consider E and G# together. That could be E major or C# minor. Given the goal of the OP to create a major or minor chord with an open tuning, there's no way to know which one is being played. Of course, E below G# will tend to be heard as E major, whether or not that's the intention. But G# below E is wholly ambiguous. Commented Sep 14, 2021 at 5:09
• @guestposter "if you insist a chord isn't a chord without a perfect fifth..." well sorry to say, but most people do. The idea behind an open tuning is that strumming all the open strings at once makes a specific chord, and OP wanted to look for major or minor chords specifically. You did get half the question, though, since those are regular tunings that make a chord. Commented Sep 15, 2021 at 21:54