Noctave
The piece
Debussy wrote two Arabesques for piano; this is the first, a work of his youth. Its title points to an ornamental line that curls back on itself, and the piece opens precisely with triplets that rise and fall again, played by both hands together. After a first part in E major, Andantino con moto, a slower central section in A major, Tempo rubato (un peu moins vite), brings a simpler melody, before the opening motion comes back.
Rhythm is the crux here: over some fifty beats, one hand’s triplets run against the other hand’s eighth notes. You need three notes against two, without either hand swallowing the other’s rhythm. Start by tapping the pattern on a table, then play it slowly, noting the one note that falls together on each beat. The two hands share the notes equally; on the left, these are often wide arpeggios beneath the right hand’s triplets, to be kept even and unaccented. A light pedal, changed often, keeps the lines clear.