These sonatas were originally composed for two flutes (or oboes/recorders) without basso continuo. Although some modern editions may suggest a basso continuo part, but the primary historical and standard published versions are for two unaccompanied melody instruments, which is how they are presented in this edition.

The “Priestman IX” designation refers to the thematic cataloguing by Brian Priestman to distinguish John’s works from those of his relatives, Jean-Baptiste Loeillet de Gant and Jacques Loeillet