There are four main national (Germany, France and Vienna) models in which composers of the classical era drew upon. Each of these models pertains to its nationalistic conventions and thus differing based on location. These four main models are as follows: the Trio Sonata (Baroque), the instrumental sonata with obligato keyboard accompaniment, the Keyboard sonata/piece with optional or obligato instrumental accompaniment and lastly, the Divertimento. The Baroque Trio Sonata, the only international genre, generally consists of three to four movements as well as featuring two instruments with independent parts and of course, basso continuo (consisting of a bass instrument and the keyboard). The importance of the keyboard, in this particular genre, is rather minimal as it does not feature any sort of “compositional independence.” This lack of independence is the result of a figured bass in which the performer is to play “unobtrusively”, unlike that of the obbligato style. An example of this genre is J.S. Bach’s Allegro, Sonata, from Musical Offering BWV 1079. Next, the Baroque Keyboard obbligato Sonata from Germany, consists of one instrument and the keyboard. Also, just like the Baroque Trio Sonata, the Baroque Keyboard obbligato Sonata typically features three to four movements. The conception is that this genre features two equal melodic lines (one instrument and the right hand of the keyboard) as well as the supporting bass line performed by the left hand of the keyboard performer (no cello). Two examples of the Baroque Keyboard obbligato Sonata are: J.S. Bach’s Sonata for Viola da gamba and Harpsichord in g and C.P.E. Bach’s Sonata for Flute and Fortepiano in C, W 73. The third main national model is from France and it is the Baroque Keyboard Piece with instruments. This genre consists of an independently conceived keyboard piece and either, obbligato or optional instrumental parts. With obbligato, the conception is that this genre consists of one fully independent keyboard part as well as one fully independent and obbligato instrumental part (there is no influence of basso continuo and no doubling of the left hand by a bass instrument). Two examples of the Baroque Keyboard Piece with obligato instrumental accompaniment is: Mondonville’s Pièces de clavecin avec accompagnement de violon, op.3 (1734) and his Pièces de clavecin avec voix ou violon, op.5 (1748). The conception of this genre with optional instrumental parts is that there is one fully independent keyboard part and two partially but optional instrumental parts (no doubling of the left hand by a bass instrument). An example of the Baroque Keyboard Piece with optional instrumental accompaniments is Jean-Philipe Rameau, Pièces de clavecin en concerts.
Not being entirely truthful and in an effort to sell more music, Rameau writes:
These pieces lose nothing by being played on the harpsichord alone; indeed, one would never suspect them capable of any other adornment; such, at least, is the opinion of several persons of taste and skill whom I have consulted on this subject…
The fourth and final main national model is the Divertimento of the Viennese tradition. The scoring of this particular genre includes: one or more treble instruments, piano (of basso continuo nature) and cello (doubling the left hand of the piano). The conception of this genre, although slightly skewed, is generally not that similar to that of a keyboard sonata with accompaniment, although instances do indeed occur. Incidentally, the texture is closely related to that of the Baroque Trio Sonata. An example of a Divertimento is Leopold Hofmann’s (1738-93) Divertimento in F.
The two main models that influenced Haydn’s chamber music are: the Divertimento and the solo piano sonata. His earliest works continued in the Viennese tradition of the Divertimento. This influence is evident in, the cello doubling the left hand of the keyboard and the independence of both the violin (soprano instrument) and the right hand of keyboard part (similar to that of the [trio sonata]). Under the employment of the Esterhazy family, Haydn published thirteen works for violin, cello and piano. These works feature, minimal continuo-type writing, however, the cello is still mainly doubling the left hand of the keyboard (hence independence of the cello is rare). Furthermore, the violin either doubles the right hand of the keyboard, fills in the harmony or is in dialogue with the keyboard. His greatest model of influence during this time was the solo piano sonata. In the 1790s, Haydn, while in London and Vienna, published fourteen works for violin, cello and piano (modeled after the solo piano sonata) that feature: both violin independence (dialogue) and an accompanying nature, more cello dependence from the left hand of the keyboard, improvisation that appears to provide inspiration and lastly, music that was composed for professionals rather than amateurs.
The models that influenced Mozart’s chamber music were: the Baroque Keyboard Piece with instruments from the tradition of Mondonville, Rameau and Schobert and somewhat minimally, the Divertimento. Mozart’s Sonatas for piano with accompaniment of violin or flute and cello op.3 (K.10-15) are indicative of the Viennese Divertimento tradition, for not only does the cello double the left hand of the keyboard, but also, the treble instrument has remarkable independence. As an aside, these works were modeled after J.C. Bach’s two movement structure. His Sonatas for piano with violin accompaniment (K. 301-306) feature: the use of the violin for cantabile melodies, the demise of the cello doubling the left hand of the keyboard part and lastly, a much larger scale composition in comparison to his solo piano pieces. The final decade of Mozart’s chamber music features constant dialogue between the violin and the keyboard, so much so, that they are often equal partners. Additionally, in K.496, K. 498, K. 502 K.542, K.548 and K. 564, his use of the cello is a little surprising in that it is often doubling the left hand of the piano, although at times, independence is evident.