What is the difference between baroque and classical concertos?

Answer 1

The term 'Fortspinnung' is frequently used to define Baroque music. Fortspinnung is a German word that describes the constantly unfolding nature of the music. When you listen to music from the Baroque, you will notice that it rarely comes to a complete stop. Even at Cadences, one or more voices lead into the next phrase.

By Contrast, music from the classical period has a much stronger focus on phrase units. Try listening to a Bach Prelude and Fugue (Baroque) and a Mozart piano Sonata (Classical) and comparing the phrasing. You can find some good examples on YouTube. You may also notice some differences in the texture.

Baroque music has a strong focus on counterpoint, or line against line. If you listen to a Bach Fugue for example, you will probably notice that there are several different lines moving freely of each other. One may leap up while the other leaps down, or one may step down slowly while another is moving quickly in many different directions.

Classical Music has a focus on harmony, or chords. While there are still different lines in much of Classical music, you will notice that there is a more distinct melody with a chordal accompaniment.

Answer 2

They both typically have 3 movements, fast, then slow, then fast again. Within the movements, they both alternate the tutti (full orchestra) with the soloist or soloists; typically the tutti begins and ends a movement, and returns during the movement in different keys.

Where they differ is in the formal structure of the key changes and especially the repetition and development of themes. The Classical era was all about these formal structures, such as the sonata form and rondo. The merging of the Baroque concerto idea with the Classical forms created some interesting questions.

The first movement of a Classical concerto would typically be in sonata form. Would the opening tutti do all of the exposition of the themes? Or would the tutti bring in the first theme (or theme group), then the soloist bring in the second? Would the change from the opening key to the contrasting key occur during the tutti, during the solo, or at the entrance of the solo?

One of the common ways to do this in the early Classical era was the "double exposition," in which the tutti presented most of the themes, but all in the home key; then the solo entered in the home key, took up the first theme and modulated to the contrasting key for the later themes. This raised a question for the recapitulation: would you really repeat all of this material from the exposition twice (once from the tutti, then from the soloist), all in the home key? Or would you abridge the material somehow?

The sonata form and the concerto principle of alternating tutti-solo were an awkward fit, which brought out the ingenuity of the composer to find a satisfying solution.

The third movement of the Classical concerto would often be a rondo, a simpler form more similar to the old Baroque technique of straightforward tutti-solo alternation in different keys. This form allowed the concerto to end on a lighter note as a counterbalance to the more complex first movement.