Some of the interior scenes of Madame Nadedja von Meck's estate would later be used in Stanley Kubrick's Barry Lyndon (1975).
In a biography of Alan Bates, director Ken Russell mentions that he offered Bates the lead role of Tchaikovsky during the filming of Donne in amore (1969). Although Bates admired the script, he turned the role down. Director Russell felt this was because Bates "thought it might not be good for his image to play two sexually deviant parts in rapid succession."
Ken Russell offered the leading role of Sister Jeanne to Glenda Jackson in I diavoli (1971), his follow-up film to L'altra faccia dell'amore (1971). Jackson refused, as she did not want to play another over-the-top sexually neurotic female character so soon after Antonina. The role went to Vanessa Redgrave.
The extras playing (miming) the orchestra in the scene featuring Pyotr Ilyich Tchaikovsky playing the 1st Piano Concerto were mostly from the Bristol University Music Department Orchestra. They were paid 7 guineas a day (£7 and 7 shillings) each - the extras in the audience were only on 5 guineas. The scene was filmed in the Music Room of Bath Spa.
Many years after appearing in this film as "Alexei," Bruce Robinson remembered it by remarking (of director Ken Russell) that "Ken was starting to lose his marbles" during the filming.