Servais and Grégoir - Fra Diavolo, 2me Grand Duo Brillant (Urtext edition)

Perhaps the most widely known example of the cello–piano opera fantasy genre is the Grand Duo Concertant sur des thèmes de Robert le Diable by Frédéric Chopin and Auguste Franchomme. A fine and lesser-known example, however, is the Deuxième grand duo brillant based on Daniel Auber’s opéra comique Fra Diavolo, composed by Joseph Grégoir and François Servais. In this work, both the piano and cello parts are treated as equal partners, engaging in a rich musical dialogue that evokes the style of late Beethoven or Mendelssohn sonatas. The cello writing is highly virtuosic, in the spirit of Servais’s more demanding works such as Souvenir de Spa and Carnaval de Venise. To aid less advanced performers, Servais included ossia passages in several challenging sections; all are preserved in this edition. The work is dedicated to Mademoiselle Louise Cotelle.

One of the main interpretive challenges in performing the Fra Diavolo Duo is selecting appropriate tempos. Auber includes metronome markings in his opera, which, for the most part, work well within the Duo. The piece opens with Diavolo’s Act III aria (“Il faut nous hâter, le temps presse”), marked dotted quarter = 112, is fully playable at this tempo in the Duo. Measures 93–127 are based on the section “Par charité, laissez-moi, je vous prie,” which, while not given a tempo by Auber, benefits from a characteristically cautious tempo (dotted quarter = 76–80), reflecting Diavolo’s mocking tone. The following section, “Nous ne demandons rien” (mm. 128–147), can be played around quarter = 100, with expressive rubato for the cello’s up-bow staccato.

The next major segment (beginning at m. 235) is built on Lorenzo’s romance, “Pour toujours, disait-elle,” which Auber assigns quarter = 120. This works well as a starting tempo, but adjustments should be made for the variation section (mm. 264–293), which benefits from a more moderate pace (quarter = 72–80). If the contrast feels too abrupt, performers may consider starting closer to quarter = 100 at m. 235. The final part of the Duo (m. 296 to the end) draws from Milord’s couplets “Je voulais bien,” for which Auber prescribes quarter = 126. Anywhere from 116 to 126 would be suitable, but once the piano launches into runs and flourishes, a more elastic tempo (quarter = 76–84) is appropriate. The closing bars can return to the original tempo.