The Beatles · from Let It Be (rooftop concert, Jan 1969) · McCartney composition
A study in pure A mixolydian with no 5-chord anywhere and a ♭7-to-4 cadence.
The palette is A, D, G (1, 4, ♭7). No E chord appears in the song, which is the signature that confirms A mixolydian instead of A major. The chorus tag G to D is the classic mixolydian cadence, ♭7 to 4, resolving via a rocking plagal move instead of a V-to-I.
The home key is A, but not plain A major. It is A mixolydian, a mode that is like A major with a lowered seventh note (G natural instead of G-sharp).
The whole song uses only three chords: A, D, G.
The tell that it is mixolydian and not major is that there is no E chord anywhere in the song. In plain A major the 5-chord (E) is the strongest chord in the key. Its absence is the signal that A mixolydian is the true home.
The chorus ends on G-D, which is a mixolydian cadence (the ♭7-chord going to the 4-chord). That is a rock-and-roll close instead of a classical V-to-I.
The verse uses power chords (A5, D5) for a driving riff, and the chorus adds sevenths (A7, D7) for a bluesy color.
To see the exact chords and key, open Pollack or Isophonics.
The home is A, but the palette is A, D, G (1, 4, ♭7). G natural is the lowered seventh degree of A major, which is the defining note of A mixolydian.
The song is in A mixolydian because the ♭7 (G) is a chord in the palette while the diatonic-major 5 (E) is not. In tonal music the presence or absence of the 5-chord is the primary test for mode.
The verse rocks between A5 and D5, the 1 and 4 chords voiced as bare-fifth power chords with no third. That is a classic driving-riff sound built for a rooftop concert.
Removing the third from the chord is a modal move: without an F# or F natural in A5, the chord does not commit to major or minor, which keeps the mixolydian ambiguity open.
The chorus adds sevenths: A7 (1(7)), D7 (4(7)), then closes on G to D (♭7 to 4). That final G-D is the mixolydian cadence, a rock-and-roll substitute for the V-to-I close of tonal-major music.
The ♭7-to-4 shape is the same close used in Van Morrison's Brown-Eyed Girl, Sweet Home Alabama, and every rock song that avoids the classical V chord.
The strongest evidence for A mixolydian is negative: there is no E chord (the diatonic 5 of A major) in any section of the song, verse, chorus, or solo.
Absence of the V chord is the classical marker of a modal piece. When the 5 is missing and the ♭7 is present, the key center has shifted from major to mixolydian.
The full structure is a short intro, verse, chorus, verse, chorus, guitar solo, verse, chorus, plus the rooftop coda repeated tags on A. No bridge, no modulation, no borrowed chord outside the palette.
The whole song is three chords: A, D, G, in power-chord voicings for the verse and dominant-seventh voicings for the chorus.
| Degree | Chord | Nashville | Roman |
|---|---|---|---|
| 1 | A (A5, A7) | 1 (1(5), 1(7)) | I |
| 4 | D (D5, D7) | 4 (4(5), 4(7)) | IV |
| ♭7 | G | b7 | ♭VII (mixolydian ♭7) |
Chords sourced from a public transcription, in A mixolydian.
Reading the numbers: each is a scale degree in A. Plain = major-quality, (5) = a bare-fifth power chord (no third), (7) = a dominant-seventh coloring, ♭7 = the lowered seventh degree of A major, which is the defining chord of A mixolydian.
The three chords in their common voicings (low E to high e; x = mute).
Prose analysis of the mixolydian palette, the ♭7-to-4 cadence, and the missing V chord.
Open Pollack mirror →Downloadable chord and key files (per-album zip that includes Get Back).
Open Isophonics →Roman-numeral function and melody for the verse and chorus.
Open the song page →