BaroqueC major100 bpm~2 mindifficulty 6/9
Bach's Two-Part Inventions, BWV 772–786 are foundational keyboard pedagogy. He compiled them around 1723 for his eldest son Wilhelm Friedemann, with a famous title-page that lays out their explicit purpose: to teach a clean, two-voice cantabile style, to introduce three- and four-voice writing, and to encourage "a strong foretaste of composition". The C-major Invention is the first and best-known piece in the set.
Technically the Invention tests two-part counterpoint at a mature level. Both hands carry equal melodic lines that imitate, invert, and answer each other across the piece; the student must voice each line as an independent melody rather than as a foreground-and-accompaniment texture. The thematic material is a single short motif that Bach develops, inverts, and recombines for the entire two minutes — the structure is an essay in motivic economy.
Two pitfalls. First, students often play the right hand cleanly and let the left hand chug along — the piece is a contrapuntal duet, not a melody-and-accompaniment study, and the left hand has to phrase as carefully as the right. Practise hands separately, voice each line, then re-combine. Second, the ornaments (the small written-out trills) often get rushed; play them slowly enough that each note speaks before resolving.
The complete Inventions are on IMSLP in clean public-domain editions including Bach's autograph. Hearing the piece on harpsichord (several Glenn Gould-free recordings exist on institutional channels) calibrates the right cleanly-articulated touch.
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