From an early age Arthur Duff was arranging Irish and English folksongs for Percy Whitehead. Many of his Irish airs and original compositions were broadcast from the Irish station and from the BBC even before he was working for Radio Éireann. He wrote music for many amateur orchestral societies including the Dublin String Orchestra, which was under the leadership of Miss Terry O'Connor, the Dublin Orchestral Players, founded by Havelock Nelson in 1939 and the Musical Arts Society.

He belonged to the older generation of Irish composers who were all born before the turn of the century like Sir Hamilton Harty, Sir Charles Stanford and John Larchet. Duff's love for Irish folk melodies and modal harmonies must have intrigued many composers of his time. He helped foster an interest amongst his peers in Irish music. He re-created Irish tunes expressing them in his own way but keeping the character of the traditional tune. He saw in the 'folksy' music of Frederick Delius, Roger Quilter and Vaughan Williams a good model for Irish music to adopt.

The music of Philip Heseltine (Peter Warlock) bears certain resemblances to Duff as does the music of George Butterworth.

Frederick Delius' semitone chromatic movement of parts also influenced Duff. It is possible that these were imprinted on his style by Sir Hamilton Harty. Duff's admiration for Delius may also have been stimulated by E.J. Moeran who had lived for a time with Warlock. Warlock had a strong admiration for the Delian technique.These influences can be seen in his ballet, The Drinking Horn and in his Music for Strings. His evocation of eighteenth-century Dublin can clearly be heard in his Echoes of Georgian Dublin. Duff never neglected Bach. Most of his record collection was either Classical or Baroque. He was not interested in the 'heavyweight' composers such as Brahms.