Composed by J. S. Bach for Flute and Piano, this edition of 4th Sonata was arranged for Alto Saxophone in E flat and Piano by Marcel Mule. Its difficulty would fit the skills and abilities of intermediate players.

In terms of composition, this piece was created in three different sections: the first one is divided into three parts (Andante with a tempo at 96, Allegro at 116 and Adagio at 72) followed by Minuet and Minuet 2.

Marcel Mule (1901-2001) is one of the greatest French saxophonists, renowned worldwide for his work on the classical Saxophone repertoire. He was teaching his students how to obtain a good quality of sound and believed it was dependent on the embouchure, the emission, the mastery of vibrato and thus of breathing. He wrote different methods that focus on technique, articulation and tone productions such as 'Scale and Arpeggios' (in three books), 'Daily exercises after Terschack' or '30 Great exercises or studies after Soussmann' (in two books), among others.