The Adagio cantabile from Beethoven's Sonata No. 8 places a broad, singing melody over a gently moving accompaniment. Its opening in A-flat major gives this movement a different sound from the sonata's C-minor outer movements. The melody returns several times, but the music around it changes: additional inner notes, repeated chords, and triplet figures gradually make the texture more active. Stronger passages briefly disturb the calm before the opening melody returns and the final phrases become quiet again.

Measures 1-8 introduce the main theme. The right hand carries the longer melodic notes while the left hand combines a moving middle line with lower bass notes. The melody includes small decorative figures at the ends of phrases. Even in this relatively spare opening, the accompaniment contains notes that must continue sounding while other notes move around them.

Around measures 9-15, the theme appears with a more active inner part in the right hand. Both hands now contribute to the continuous motion beneath the melody. The upper line remains easy to follow, while the accompanying notes fill more of the space between its longer tones. The phrase gradually settles before the contrasting material begins.

Around measures 16-27, repeated notes and chords replace much of the opening accompaniment. Short melodic figures rise into a higher register, then move downward through decorated phrases. The hands briefly exchange the melodic activity, and the texture thins as this section approaches the return of the opening theme. Around measures 28-35, the familiar melody and its original kind of accompaniment are heard again.

Around measures 36-50, triplet motion becomes prominent. Repeated inner chords support a melody above them, and the moving figures later shift into the left hand. Accents and additional sharps change the sound of this passage. The two hands alternate between holding parts of the harmony and filling the space with smaller notes.

From around measure 51, the opening melody returns over a triplet accompaniment. The more active subdivision continues as the right hand also adds inner notes. On the last page, short decorative runs lead into the closing phrases. The bass and melody gradually separate into quieter gestures, and the movement ends with soft, widely spaced chords.

Interesting fact: The movement keeps its 2/4 meter even when the accompaniment changes from groups of four sixteenth notes to triplet figures.