Guitar tuning

Celtic CGDGAD Tuning (C-G-D-G-A-D)

CGDGAD is a modal guitar tuning closely related to DADGAD. The four treble strings are identical in both; only the two bass strings change, each dropping a whole step from DADGAD — the sixth from D to C and the fifth from A to G. You get a deeper foundation and an open chord with no third in it, so it is neither major nor minor.

The tuner opens already preconfigured; you only need to allow microphone access.

Strings and frequencies

What chord is CGDGAD?

The open strings ring C, G, D, G, A and D. Strip out the repeats and four distinct notes remain: C, D, G and A.

Those four are a chain of perfect fifths — C-G-D-A. There is no third anywhere in it, which is why the tuning sounds neither major nor minor. That is the whole point of a modal tuning: the chord refuses to commit, and the melody decides.

Read against the low C, the notes are the root (C), the ninth or second (D), the fifth (G) and the sixth (A). The closest name for that is a C6/9 with no third; it is also written as Csus2 with an added sixth. Both labels describe the same handful of notes, and what matters for playing is the missing third.

Set against DADGAD, which rings a Dsus4, CGDGAD has four distinct notes sounding instead of three, and its bass sits a whole step lower. It sounds wider and less hollow — and it asks for slightly more care, because in DADGAD almost anything fits over the drone and here it does not.

CGDGAD vs DADGAD, string by string

The difference is smaller than it looks, and you can read it straight off the two frequency tables.

The four treble strings are identical in both tunings: fourth on D (146.83 Hz), third on G (196.00 Hz), second on A (220.00 Hz) and first on D (293.66 Hz). Nothing moves up there.

Only the two bass strings change, and both drop exactly one whole step. The sixth goes from D (73.42 Hz) to C (65.41 Hz) and the fifth from A (110.00 Hz) to G (98.00 Hz).

That has a very convenient consequence: anything you already play in DADGAD above the fifth string transfers here unchanged. Only what rings underneath is different. It works the other way too — learn something in CGDGAD and moving it to DADGAD is a matter of raising two strings a step.

Against standard tuning the change is bigger: four strings come down. The sixth drops two whole steps (E to C), the fifth one step (A to G), the second one step (B to A) and the first one step (E to D). The third and fourth stay where they were.

CGDGAD chords: three shapes that need one finger

Every shape below can be checked against the frequency table above, which is where they come from.

• C major: fret only the fourth string at the second fret, taking the D up to E. You get C, G, E and G — a complete C major. Let the second and first strings ring as well and it becomes the C6/9 of the open tuning.
• G major: fret only the second string at the second fret, taking the A up to B, and leave the sixth string out. You get G, D, G, B and D — a G major with a doubled fifth.
• Straight barre: one finger across all six strings at any fret repeats the open chord, transposed. At the second fret it gives D, A, E, A, B and E — the same structure over D.
• C drone: let the open sixth and fifth ring (C and G) while the melody moves on the three treble strings. This is what the tuning is for, and the reason it exists.

Note that C major and G major both come out of a single finger at the second fret, on different strings. That pair covers a great deal of what gets played in the key of C, and it is why the tuning feels so generous once you find your way around it.

How to tune to CGDGAD from standard

Four strings, all going down. Nothing goes up, so total tension on the neck falls and there is no risk to the guitar.

Start with the first string: down a whole step, E to D, until it matches the open fourth string an octave above.

Then the second: down a whole step, B to A. With those two done, the first and second strings already match DADGAD.

Drop the fifth a whole step, A to G: it should match the open third string an octave below.

Finish with the sixth, which moves furthest — two whole steps, E to C. It is the lowest note in the guitar catalogue, the same one Open C reaches, and it ends up very slack, so go slowly and use the tuner on this page; by ear it is easy to overshoot.

With all four done, strum the open strings. It should sound wide and unresolved, with the C well underneath. If you hear a D at the bottom, the sixth or the fifth has not come down.

Why these tunings are called Celtic

The name comes from the repertoire the tunings took hold in, not from where they came from. DADGAD, the reference point of the family, was worked out by the British guitarist Davey Graham in the early 1960s after hearing an oud player in Morocco; applying it to British and Irish folk is what tied the name to it.¹

CGDGAD extends the same idea and inherits the label by association. Its reason for existing is acoustic rather than historical: the open strings put C and G low down, where they behave like a bagpipe drone, and the melody sits over that drone on the treble strings without anything needing to be damped.

So "Celtic" describes what the tuning is used for, not where it is from. In the case of this one it also describes the company it keeps — DADGAD's — more than a tradition of its own.

How it sounds

It has a modal, spacious character with a noticeably deeper low end than DADGAD. It works very well for backing folk melodies and for building atmospheres with many open strings ringing at once.

The C on the sixth string is the lowest note in the guitar catalogue on this site, tied with the C of Open C, two whole steps below standard E. That gives it an almost piano-like bottom end — and it is also what forces you to think about the gauge of that string.

Styles and genres

Recommended string gauges

Dropping the sixth two whole steps, E to C, takes away a little over a third of its tension. On a normal acoustic set that string goes soft and buzzes under hard picking.

A 0.012-0.053 set is the sensible minimum; on a 0.013-0.056 the sixth behaves far better. If the guitar is going to live in this tuning, what really fixes it is a single sixth string of 0.060 or heavier, as long as the nut slot takes it.

The fifth drops only a whole step and copes fine with normal gauges. The other four barely move or do not move at all, so leave them alone.

Tuning tip

Explore three-note chords on the middle strings while the open C, G and D ring below: you get rich harmony without difficult fingerings, and it is exactly what this tuning does better than standard.

Frequently asked questions

What is CGDGAD tuning?

It is a modal guitar tuning: C, G, D, G, A, D from the sixth string to the first. Against standard tuning four strings come down — the sixth by two whole steps, and the fifth, second and first by one step each.

Is CGDGAD the same as DADGAD?

No, but they are close. The four treble strings are identical in both tunings; only the sixth and fifth differ, dropping one further whole step each in CGDGAD. If you were looking for Celtic tuning in general, DADGAD is almost certainly the one you want, since it carries nearly all of the repertoire.

What chord do the open strings make in CGDGAD?

C, G, D, G, A and D, which is four distinct notes: C, D, G and A. They form a chain of perfect fifths and contain no third at all, so the chord is neither major nor minor. Read over the low C it is a C6/9 with no third.

What chords can you play in CGDGAD?

The two most useful ones need a single finger at the second fret. Fret the fourth string for C major; fret the second string and leave the sixth out for G major. A straight one-finger barre repeats the open chord transposed to whatever fret you put it on.

How do you tune a guitar to CGDGAD?

Lower four strings: the first from E to D, the second from B to A, the fifth from A to G and the sixth from E to C. The sixth moves furthest, two whole steps, and is worth doing with a tuner because it is easy to overshoot by ear.

What string gauge do you need for CGDGAD?

A 0.012-0.053 set at minimum, and better a 0.013-0.056. The sixth loses a little over a third of its tension dropping to C and goes slack and buzzy on light gauges. For a guitar that stays in this tuning, a single 0.060 or heavier sixth is the real answer.

Is CGDGAD bad for your guitar?

No. Four strings come down and none goes up, so total tension on the neck and the top is lower than in standard tuning. If you leave the guitar in it permanently, check the string action occasionally, since slack strings can start to buzz.

What songs use CGDGAD tuning?

There is no canonical list. It is mainly an accompaniment tuning for traditional repertoire, passed on through arrangements rather than through particular recordings. The songs usually cited as Celtic tuning are in DADGAD, not in this one.

Related tunings

• DADGAD: the Celtic tuning most people are actually looking for
• Open C: the same low C, but ringing an open major chord
• Open D: an open tuning in D, a finished chord rather than a modal sound
• Drop D: only the sixth string moves; the first step outside standard tuning
• Standard tuning: the starting point

Sources

1. Pierre Bensusan, DADGAD Music: Compositions from Spices and Wu Wei, Mel Bay, 1996, p. 8, for the origin of DADGAD: Davey Graham and the Moroccan oud. It is the same source the DADGAD page cites.
2. The string notes, the comparison with DADGAD and the chord shapes on this page are worked out from the frequencies in the table above, which are the ones the tuner itself uses.

Updated 2026-08-31