The sonata allegro form was used in the first movements of symphonies, concertos, sonatas, and quartets during the Classical era. It has three main sections - the exposition, development, and recapitulation. The exposition introduces musical themes in the primary key and a contrasting key, while the development builds tension through modulation and theme manipulation. The recapitulation then resolves the musical ideas by reprising the themes in the primary key.

1. Sonata Allegro Form
Developed in instrumental
music of Classical Era.

2. Was used in first movements of:
 Symphony
 Concerto
 Sonata
 Quartet

3. Structure:
 Exposition
 Development
 Recapitulation

4. Exposition:
 Slow introduction (optional)
 First theme (or theme group) and its expansion
in tonic
 Bridge – modulates to a contrasting key
 Second theme (or theme group) and its
expansion in contrasting key
 Closing theme, cadence in contrasting key
 Exposition repeated

5. First theme or theme group
establishes a home key (tonic).
W. A. Mozart, “Eine Kleine Nachtmusik”,
K 525, First Movement: Allegro

6. Theme 1

7. Theme 2

8. Theme 3

9. Bridge – transition between first
and second groups.
Modulates to a contrasting key

10. Second theme or group of themes in
contrast key.
Theme 4.

11. Theme 5.

12. Theme 6 (closing theme).

13. Development.
 Builds up tension against the return to
tonic by:
Frequent modulation to foreign keys, and
Fragmentation and manipulation of themes
and motives.
 Transition back to tonic.

15. Recapitulation
 First theme (or theme group) and its
expansion in tonic
 Bridge (rarely modulates)
 Second theme (or theme group) and its
expansion transposed to tonic
 Closing theme, cadence in tonic
 Coda; cadence in tonic

16. Exposition and Recapitulation
 Slow introduction (optional)
 First theme (or theme group)
and its expansion in tonic
 Bridge – modulates to a
contrasting key
 Second theme (or theme
group) and its expansion in
contrasting key
 Closing theme, cadence in
contrasting key
 Exposition repeated
 First theme (or theme group)
and its expansion in tonic
 Bridge - rarely modulates
 Second theme (or theme
group) and its expansion
transposed to tonic
 Closing theme, cadence in
tonic
 Coda; cadence in tonic.