Scales and modes
Ionian mode
The Ionian mode is the first mode of the major scale, with the formula 1 2 3 4 5 6 7: it is the major scale itself, seen as one of the seven modes.
What is the Ionian mode?
The Ionian mode is the first of the seven modes of the major scale. Its notes and formula are exactly those of the major scale: 1 2 3 4 5 6 7, that is whole, whole, half, whole, whole, whole, half.
In G: G A B C D E F#. In C: C D E F G A B.
Why two names? You say major scale in tonal harmony, and Ionian when you compare modes with each other: G Ionian against G Dorian, G Lydian or G Mixolydian.
How do you play the Ionian mode on guitar?
G Ionian in 2nd position, root on the low E string, 3rd fret:
| String | Frets | Notes |
|---|---|---|
| 6 | 2, 3, 5 | F# G A |
| 5 | 2, 3, 5 | B C D |
| 4 | 2, 4, 5 | E F# G |
| 3 | 2, 4, 5 | A B C |
| 2 | 3, 5 | D E |
| 1 | 2, 3, 5 | F# G A |
The Gs are on the low E string 3rd fret, the D string 5th fret and the high E string 3rd fret. To link this shape with the other positions, display G major on the fretboard with the guitar scales tool.
Which chords go with the Ionian mode?
Harmonized in four-note chords, G Ionian gives Gmaj7, Am7, Bm7, Cmaj7, D7, Em7 and F#m7♭5. Use Ionian over the I chord (G or Gmaj7) and over any progression in the key: G C D, G D Em C, or Am7 D7 Gmaj7.
The tricky note is the 4 (C in G). Held over a G chord, it rubs a half step above the third, B. Use it as a passing note, or wait for the C chord to land on it.
Exercise: Ionian, Lydian or Mixolydian?
Over a G drone (low E string 3rd fret, or a looped G chord):
- Play G Ionian in the shape above and end on B, G string 4th fret.
- Change every C to C#: you now have the brighter Lydian mode.
- Go back to C and change every F# to F: that is the Mixolydian mode, more rock and bluesy.
Then compare with the Dorian mode over an A drone: same notes as G Ionian, but a minor sound. Only one note changes between Ionian, Lydian and Mixolydian, which is the best way to hear what each degree does.
Key takeaways
- Formula: 1 2 3 4 5 6 7, identical to the major scale.
- G Ionian: G A B C D E F#.
- Play it over the I chord and major progressions.
- The 4 is a passing note over the tonic chord.
Frequently asked questions
Is the Ionian mode the same as the major scale?
Yes, note for note. Ionian is the name used when you think in modes and compare it with the other six. In a pop song in G major, you simply call it the G major scale.
What is the characteristic note of the Ionian mode?
The major seventh (F# in G), together with the major third. It sets Ionian apart from Mixolydian (♭7). Against Lydian, the difference is the perfect 4 (C) instead of the #4 (C#).
Why avoid the 4 over the tonic chord?
Because it sits a half step above the chord's third: C against B over Gmaj7. That minor-ninth rub sounds like a wrong note if it lasts; as a passing note into B or D, it sounds completely natural.
Related terms
Practise in the workshop
Take it from theory to the fretboard
Open the workshop tools and see this idea across the whole neck. Free account, no card needed.