If any Adagio deserves the label ‘melodious’, then it is the third movement of Bach’s Violin Sonata No. 3 in E major. Incidentally, Carl Philipp Emanuel referred to Bach’s six sonatas as “Clavier trios”, as the violin and the right hand of the harpsichord are equal partners, while the left hand plays a separate bass part – so they are real trio sonatas. Apparently, Bach himself also derived great pleasure from the collection of six, as he kept tinkering with them from his Köthen years (1717-1723) right up to his death, even when he was making chamber music with his Collegium Musicum in Leipzig.
In the slow opening section of the Sonata in E major, the harpsichord still has an accompanying role (although a very beautiful one, full of elegant modulations), but in the Allegro the players are already exchanging thematic material enthusiastically. The deservedly famous Adagio could almost be a classical passacaglia, if it were not for the fact that the violin soon takes on the ‘accompanying’ chords and leaves plenty of room for the harpsichord. This makes the musical entanglement complete, and the musical partners curve sensually around one another. The exuberant last movement gives a display based on two themes: at the beginning and end a flashy roller coaster of quick runs, and in the middle a more lyrical line of swaying triplets.
A capable violinist and thoroughly familiar with trend-setting Italian models, Bach undoubtedly wrote much more chamber music than has come down to us. He was not, however, much attracted to the then-dominant trio sonata form, written for two solo instruments with continuo accompaniment (improvisation over a notated bass line, usually by harpsichord or lute, with the appropriate chords indicated). On the one hand, he favoured the solo sonata without accompaniment, composing a group of six sonatas and partitas for violin, six suites for cello, and a sonata for flute, all of which are astonishing accomplishments of contrapuntal and idiomatically instrumental art. Another type of duo sonata, which he virtually created, leaned the other way, toward a more controlled version of the trio sonata texture. Bach manipulated and merged conventional forms and genres with uncommon flexibility.
The six sonatas for violin and harpsichord that he wrote liberated the keyboard from the filler functions of continuo accompaniment, creating true partnership with the solo violin. In those sonatas, the right hand of the keyboard part replaces the second solo part of the trio sonata, over an active bass line that also participates in the polyphonic give-and-take.
This is readily apparent throughout the Sonata in E, No. 3 of the set, as the violin and keyboard parts swap material back and forth in buoyant counterpoint. Less obvious is Bach’s subtle skill at thematic transformation and motif development, to use terms usually applied only to much-later music, and his moments of pulse-defying syncopation and metrical shifts. The structure of the sonata is that of the old Italian sonata da chiesa, or church sonata—four movements, slow-fast-slow-fast. The fast movements are basically abstracted dances, with three- part imitation as the main ideas are passed around between the violin and the right and left hands of the keyboard part. The slow movements function as lyrically poised preludes.
