Rondo form
The general outline of sonata form looks like this: A B A C A B A. That is, there are three themes that follow this pattern. Other iterations could look like this: A B A B' A. The A theme is referred to as the refrain as it happens with the most frequency. The rondo form is used most often in keyboard suites of the Baroque and Classical periods. It is also used as the slow finale of piano sonatas, symphonies, and Classical concertos.
Five part rondo CRK = Closely related key
Refrain 1 Episode 1 Refrain 2 Episode 2 Refrain 3
A B A C A
Tonic CRK Tonic CRK Tonic
Seven Part Rondo
Refrain 1 Episode 1 Refrain 2 Episode 2 Refrain 3 Episode 4 Refrain 4
A B A C A B' A
Tonic CRK Tonic CRK Tonic CRK Tonic
Part II - Baroque Rondeau
THe historical precursor to the Classical rondo was the French Rondeau of the Baroque period. The baroque Rondeau shows these characteristics:
- The refrain is tonally closed ending in a Perfect authentic cadence in the tonic
- The refrain is a short self-contained theme. Usually a ritornello-type phrase of eight measures.
- Each time the refrain returns in the tonic key and is unaltered.
- The episodes contain thematic material very closely related to the Refrain.
Rondos of the Classical period use the same principles of the Baroque Rondeau but with greater contrasts of themes and textures in episodes. The refrain is often longer, and could be a short binary or ternary form in its self. Seven-part rondos are most often used in finales of large works.
Part IV - Sonata Rondo form
The only diference between Rondo form and sonata rondo form is that instead of C, there is a short development of the themes found in the Refrain and first episode. So, it would look like this:
Tonic Dominant Tonic Various Tonic Tonic Tonic
A B A DEVELOPMENT A B A
