What is a MIDI Effect?

An arpeggiator is a musical tool found in synthesizers, MIDI plugins, and digital audio workstations (DAWs) that automatically breaks a chord into a sequence of individual notes played in a repeating pattern.

When a musician holds down multiple notes on a keyboard, the arpeggiator rearranges those notes into a rhythmic pattern, playing them one at a time instead of simultaneously. Common arpeggiator patterns include up, down, up and down, random, or as played. The speed of the pattern is usually synchronized to the tempo of the song.

Arpeggiators are widely used in electronic music, pop, and film scoring to create rhythmic melodies and evolving patterns. They can turn simple chords into complex musical sequences, making them a powerful tool for generating motion, energy, and texture within a musical arrangement.