This site introduces unknown Emanuel Bach (C. P. E. Bach).
ChatGPT4o writes as follows (please note that it may not be accurate):
Emanuel Bachʼs Keyboard Concerto in C Major Wq. 43-6 (H. 476) is a work composed in the 1770s, known for its particularly clear and brilliant character among his keyboard concertos. The first movement begins with a bright and energetic theme, with lively dialogues between the orchestra and the solo instrument. The fast tempo and vivid technique impart a sense of dynamism throughout the movement. The second movement is a slow movement reflecting the characteristics of the empfindsamer Stil, with an impressive lyrical and poetic melody. The delicate expression of the keyboard instrument brings depth and tranquility to the entire movement. The third movement is a light and rhythmic finale, concluding with the bright sound of C major. The technical passages of the keyboard instrument and the lively accompaniment of the orchestra harmonize exquisitely, adding brilliance to the work. This concerto is a piece that maximizes Emanuel Bachʼs mature compositional skills and the potential of the keyboard instrument, captivating listeners with its clarity and expressiveness.
[After moving to Hamburg] Despite the heavy responsibilities of producing church music, Bach continued to compose numerous instrumental works, particularly for keyboard instruments with strings. Just over three years after moving to Hamburg, he composed the "Six Easy Harpsichord Concertos" (Wotquenne Catalog No. 43), specially designed for his own publication. Like many of his keyboard works at the time, these pieces were aimed at sophisticated amateur performers. Bach offered this music to many subscribers who purchased it in advance, and publicly apologized when publication was delayed due to printing issues.
Like the first four pieces in this collection, the fifth and sixth pieces are immediately appealing works, characterized by a bold challenge to the conventions of the concerto ritornello form. The usual three movements are connected without interruption, linked by "bridge" transitional sections that prepare for the new movements.
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