By the way, I'm wondering if composers specify how many instruments are to be played in their orchestral works, as in "quinquagetet" for chamber orchestra or "centet" for symphony orchestra...

 

Guess not.

A little trivia then. The largest orchestra on record consisted of a sexcentiquadricentet. Imagine that.

 

solo Bach solo cello suite Nr. 3
duet Rossini Grand Duetto for Cello and Bass
trio Micheal Haydn Trio for Viola, cello and bass
quartet Ravel SQ
quintet Beethoven piano and wind
sextet Brahms G major Str. Sxt.
septet Beethoven
octet Stravinsky wind octet
nonet Dvorak Wind serenade / Miles Davis Birth of the Cool
dectet Gerry Mulligan Walkin' Shoes
undectet the Gooners song sung by the Arsenal Football team.
dodectet Art pepper plus 11 playing Monk's Round Midnight.
Mozart 13 wind

That's quite enough of that!

 

Ah, listmania.

solo · J.Francaix: Eloge de la Danse, 1947 · piano
duet · J.Francaix: Theme & variations, 1980, · clarinet, piano
trio · J.Francaix: Musique de cour, 1937 · flute, violin, piano
quartet · J.Francaix: String Quartet, 1937 · violin, violin, viola, cello
quintet · J.Francaix: Wind Quintet I, 1948 · flute, oboe, clarinet, horn, bassoon
sextet · J.Francaix: Divertissement, 1942 · bassoon, violin, violin, viola, cello, double bass
septet · J.Francaix: Septett, 1933 · flute, oboe, bassoon, violin, violin, cello, piano
octet · J.Francaix: Octuor, 1972 · clarinet, horn, bassoon, violon, violin, viola, cello, double bass
nonet · J.Francaix: Nonetto, à la Mozart's Quintet (KV 452), 1995 via 1784 · wind quartet and string quintet
dectet · J.Francaix: Dixtuor, 1986 · wind quintet and string quintet
undectet · J.Francaix: Variations sur un thème plaisant, 1976 · wind dectet, piano
duodectet · J.Francaix: Aubade, 1974 · 12 cellos
tredectet · um... A.Copland: Appalachian Spring, 1944 · 13 member chamber orchestra

All together an unnonagetet.