 He has conducted the Society in many of the main choral works, including Bach's St John and St Matthew Passions, the Mass in B minor, Beethoven's "Missa Solemnis", Verdi's "Requiem", Elgar's "The Dream of Gerontius" and "The Music Makers", Howell's "Hymnus Paradisi" and Finzi' "Intimations of Immortality" .Malcolm is also the author of two books concerning organist and composer Percy Whitlock.His first, "Percy Whitlock - A Biographical Study" was published to critical acclaim, as was the "Percy Whitlock Companion", a collection of letters and diary extracts of the early 20th-century composer.