J.S. Bach, the piano, harpsichord and early music tunings

Elaine Comparone, a well-regarded harpsichordist rendered a dance movement from J.S. Bach's French Suite No. 5 in G, (BWV 816) that I'd performed on the pianoforte. In the Loure, (written in G Major) I was immediately struck by a pitch disparity between our respective instruments. While Loure was composed in the key of G Major,…