Arrangements of instrumental works that change the original performing forces are a useful starting point to study Bach's compositional processes because he uses similar methods in the majority of his works. He adapts sections of Reincken's chamber work Hortus musicus for his keyboard compositions (BWV 954, 965, and 966) and retains the original keys of B-flat Major, A Minor, and C Major respectively. In some movements he retains the structure and musical substance of the work, but ornaments and condenses the material. In many of the fugal movements he only uses the subject of Reincken's work to create a new movement. In the rest of the movements, Bach balances the borrowed material with his own ideas by keeping the subject and structural elements of the original work. Bach also arranges concertos by Vivaldi and Johann Ernst for organ. He exploits the differences in capabilities between the original instrument and organ by adding counter themes to the solo lines. By comparing Bach's arrangements with literal transcriptions for organ of the original, his compositional process can be studied more carefully. Bach transcribed several of his concertos for violin and oboe into works for harpsichord in which he addresses several problems in the transcription process. In the harpsichord concerto BWV 1058, he adopts the written out version of the extemporizing process. Concertos based on works now lost show a varied order of composing the orchestral and solo lines. All of these arrangements and transcriptions show how carefully Bach handled the issue of instrumentation.

Works: J. S. Bach: Fugue in B-flat Major, BWV 954 (155, 158), Sonata in A Minor, BWV 965 (155), Sonata in C Major, BWV 966 (155, 157-58), Concerto for Organ in C Major, BWV 594 (161-62), Concerto for Organ in G Major, BWV 592 (161-63), Concerto for Harpsichord in G Minor, BWV 1058 (167), Concerto for Harpsichord in D Minor, BWV 1052 (168), Concerto for Harpsichord in E Major, BWV 1053 (168-69), Concerto for Harpsichord in F Major, BWV 1057 (169).

Sources: Johann Adam Reincken: Hortus musicus recentibus aliquot flosculis Sonaten, Allemanden, Couranten, Sarabanden, et Giguen (155-60); Vivaldi: Violin Concerto in D Major RV 208 (161-62); Johann Ernst of Saxe-Weimar: Concerto in G Major (161-63); J. S. Bach: Violin Concerto in A Minor, BWV 1041 (167), Brandenburg Concerto No. 4, BWV 1049 (169).

Index Classifications: 1700s

Contributed by: Danielle Nelson