A piano melody can float over a left hand that seems to turn the same small shape again and again. One familiar version is Alberti bass: the notes of a chord are played in a repeating low-high-middle-high order instead of sounding together.
The Open University’s musical-score glossary gives this pattern, while its lesson on piano textures compares chordal accompaniment with broken-chord movement. The point is not only which notes are present, but how their arrangement changes the music’s motion.
Hear the chord inside the movement
Using a C-major triad as a simple example, C-G-E-G follows the low-high-middle-high pattern when those notes are placed in that order of pitch. The example is a small demonstration, not a quotation from a particular composition.
Imagine those notes sounding together first. Then imagine them spread evenly across time. The harmony can remain recognisable while the surface feels more active. Meanwhile, the melody above may move at a different rhythm.
Try listening twice
On the first pass through a short piano passage, follow only the tune. On the second, follow the lower accompaniment and notice where its harmony changes. You may hear a repeated shape continue while the notes themselves move to another chord.
If you have a keyboard, play the simple four-note example slowly with a relaxed hand, then stop. Do not stretch into an uncomfortable position to copy a recording’s speed. A teacher can help with fingering if you want to develop the pattern beyond listening.
Not every broken chord is Alberti bass
An ascending arpeggio, a different repeating order or a freely moving bass line may create another texture. Naming everything “Alberti” because it sounds busy removes the useful distinction.
When describing a performance, mention what you heard: a steady low-high-middle-high figure, a melody above it, and the point where the accompaniment changed. That observation is more valuable than guessing a label from the composer’s era. The pattern gives you a small, concrete way into hearing how a piano can suggest several layers at once.