Complex sentence: In music, a drone is a harmonic or monophonic effect or accompaniment where a note or chord is continuously sounded throughout most or all of a piece, sustained or repeated, and most often establishing a tonality upon which the rest of the piece is built.
Split into simpler sentences: In music, a drone is a harmonic or monophonic effect or accompaniment where a note or chord is continuously sounded throughout most or all of a piece. It most often establishes a tonality upon which the rest of the piece is built.