Alberti bass
The Alberti bass is an accompaniment figure made of broken chords, usually in the left hand on the piano. The notes of a chord sound one after another in the order lowest, highest, middle, highest note. A well-known example is at the beginning of Mozart’s Sonata in C major K. 545, which is in the sheet music archive.
- Note order
- lowest – highest – middle – highest note
- Usually in
- the left hand on the piano
- Name
- after the Italian composer Domenico Alberti
- In the archive
- Mozart, Sonata in C major K. 545, 1st movement, from bar 1
An accompaniment figure made of broken chords
In an Alberti bass a chord is not struck all at once but played note by note in a fixed order: first the lowest note, then the highest, then the middle one, then the highest again. This creates an even motion above which the right hand plays the melody. The order is not laid down very strictly; similar patterns are called by the same name too. The figure is named after the Italian composer Domenico Alberti.
Left hand in Mozart’s K. 545, bars 1 to 3
This is how the left hand appears in the sheet music archive, in the treble clef. The marked group shows the pattern: C4 (lowest note), G4 (highest), E4 (middle), G4 (highest). Every bar has two such groups of four eighth notes.
The same bars as chords
If you combine the notes of each group of four, you get chords: a C major chord in the first bar, then D, F and G (notes of the dominant seventh chord G7 without B) and back to C major; in the third bar C, F and A (F major with C in the bass) and C major again.
Mozart, Sonata in C major K. 545
At the beginning of the first movement of Mozart’s Sonata in C major, filed in the archive under “Sonata facile”, the left hand plays an Alberti bass. In the archive’s edition it is written in the treble clef; its notes lie around middle C. When the chord changes, the notes of the figure change too, while the order low – high – middle – high stays the same:
| Note of the group | 1st | 2nd | 3rd | 4th |
|---|---|---|---|---|
| Position in the chord | lowest | highest | middle | highest |
| K. 545, bar 1 | C4 | G4 | E4 | G4 |
| K. 545, bar 2, second half | C4 | G4 | E4 | G4 |
| K. 545, bar 3, first half | C4 | A4 | F4 | A4 |
In the second bar the first group begins with D4 instead of C4; the chord is a different one here, and the position of the notes changes with it. The pattern is still easy to recognise.
Alberti bass in the sheet music archive
-
Sonata No. 16 in C major, 1st movement: Allegro Wolfgang Amadeus Mozart (1756–1791), “Sonata facile”, KV 545 according to the sheet · piano · 4 pages
“Allegro” is printed above the first staff, time signature C. The right hand begins mp, the left hand p; both staves are in the treble clef. In bars 1 to 4 the left hand plays even eighth notes in groups of four, in the first bar C4 – G4 – E4 – G4, with the fingering numbers 5, 1 and 3 above the first three notes.
Common mistakes
- Accenting the highest note: The thumb plays the highest note twice per group; if it gets loud, the accompaniment sounds restless. The melody is in the right hand.
- Calling every broken chord an Alberti bass: Broken chords come in many forms; the Alberti bass is the accompaniment figure with the order low – high – middle – high.
- Always expecting the Alberti bass in the bass clef: In the archive the left hand is written in the treble clef, because its notes lie around middle C.
Continue on Maikstrings
Related terms
AccompanimentArpeggioChordDominant seventh chordPianoSonataSonatinaClassical periodBasso ostinatoFigured bass
Editor: Maik Krohm · reviewed on 4 October 2026
← Back to the glossary