>When one looks at the description on the back of a symphonic CD,
>one is likely to find each movement characterized by the tempos to
>be employed-allegro, moderato, presto, etc. Yet in an opera, sections
>tend to be designated by their form-aria, cavatina, duetto, etc. I've
>concluded that this is because most orchestral movements are composed
>of some version of sonata form. I have noticed that sometimes other
>forms are identified (and, in these cases the tempo is omitted) as with
>menuetto and trio, rondo, theme and variations, etc.
>Am I on the right track? Is this a convention with a rationale or is
>it simply tradition?
I think the composer has to communicate to the performers, and also
"sell" the work. The title of a movement could be chosen to make it
interesting to the players, as well as to describe the tempo, or do both.
For the first movement, for instance, you often get such descriptions
as Allegro, Allegretto, Largo-Allegro-LArgo, Allegro giusto, etc. The
third movements are often decribed by form: Minuet, Scherzo, etc. The
last movement is again tempo or form, or a combination (Rondo, Presto,
I guess I didn't say anything new . . .