It has generally been accepted that Bach's transcriptions were simply learning exercises. However the level of composition already reached and evidenced in his Weimar instrumental and organ works, as well as those of earlier years, hardly shows need for simple transcription as a means of further education. More likely was the challenge of accurately transforming an orchestral concerto, with its alternation of soloists and full orchestra, into a work for solo instrument, albeit a two manual harpsichord with its ability to couple keyboards for a tutti effect. This would have been an interesting and amusing way for Bach and his fellow musicians to familiarize themselves with the currently fashionable compositions without the need for orchestral parts and the gathering of the full band. The technique of rendering an orchestral form as a solo harpsichord piece would be re-visited many years later at Leipzig with the Italian Concerto, BWV 971.

Further evidence that these concertos were mature works rather than mere exercises can be found in Bach's treatment, as Sylvia Marlowe has observed.

"It is interesting and instructive to place side by side one of Vivaldi's original concerti and Bach's transcription of it. The Vivaldi score for solo violin, ripieno strings (that is, a string orchestra for "filling out"), and continuo (that is, a keyboard instrument to supply the basic harmonies) is condensed by Bach into a simple score for keyboard solo. While this condensation is going on, a compensating expansion occurs on another level. Bach makes the bass more active, enlivens the inner parts, supplements the original solo violin passages with new counterpoints, paraphrases certain violinistic effects with equivalents in the keyboard idiom, writes out the embellishments (trills, mordents, slides, etc.) that the Italians left almost entirely to the discretion of the performer. In short, Bach does not give us literal translations but artistic adaptations. The concerti became genuine clavier pieces, to be played with no less delight and pleasure than Bach's original creations as Bach's biographer Philipp Spitta observed."

Ms Marlowe makes judicious use of the 16', as new evidence has definitively shown Bach would have done. Her phrasing, precision and technique are, as always, exemplary. Illustrated article: The Baroque German Harpsichord

We have included two Vivaldi originals for comparison.