Alberti bass
An accompaniment figure of broken triads at the piano.
What it means
The Alberti bass is an accompaniment figure for the left hand at the keyboard, in which a triad is broken up in even note values, namely in the succession lowest, highest, middle, highest note. For a C major triad this gives C–G–E–G. The figure repeats as long as the harmony remains, and changes with it.
In the notation
The figure appears in the lower staff as an even succession of eighths or sixteenths, usually in close position and in the middle register. Through the repetition of the same pattern it is recognisable at a glance. The name is associated with an eighteenth-century composer in whose music the figure occurs especially often; he did not invent it, and it is attested before him too.
Musical use
The figure had its heyday in the piano music of the early Classical and Classical eras. It fulfils two tasks at once: it keeps in motion the harmony, which on the keyboard instruments of the time would otherwise soon have faded, and it creates an even rhythmic ground over which the melody of the right hand can sing freely. Since the lowest note stands at the beginning of every group, the bass also stays audible.
The Alberti bass is to be distinguished from other accompaniment figures: from the simple broken chord in ascending or descending succession, from the repetition of a single note called drum bass, and from octave accompaniments. It is one particular form of chord breaking, not its umbrella term.
The figure is named after Domenico Alberti, an Italian composer of the early eighteenth century. It reached its peak in the piano music of the Viennese Classicism, where it gives the melody of the right hand an evenly flowing harmonic foundation. Since the figure keeps the chord constantly in motion, it replaces the long-sounding chord on the fortepiano and the harpsichord.
Performance practice
Play the Alberti bass quietly and evenly — it is ground, not figure. Give the first note of each group a touch more weight, so that the bass line carries, and keep the recurring upper notes especially light. Practise the hand from the wrist rather than from the fingers, so that the motion stays loose. And at the modern grand watch for sparing pedal, or the figure blurs.