Hexachordum Apollinis

Hexachordum Apollinis (PWC 193–8, T. 211–6, PC 131–6, POP 1–6) is a collection of keyboard music by Johann Pachelbel, published in 1699. It comprises six arias with variations, on original themes, and is generally regarded as one of the pinnacles of Pachelbel's oeuvre. The collection includes a preface in which Pachelbel dedicates the work to Dieterich Buxtehude and Ferdinand Tobias Richter and briefly discusses the nature of music.

Hexachordum Apollinis (the title roughly translates to "Six Strings of Apollo") was published in 1699 in Nuremberg by Johann Christoph Weigel, a publisher who had worked with Pachelbel before. The frontispiece, created by Cornelius Nicolaus Schurz, describes the collection as "six arias to be played on the organ, or the harpsichord, to whose simple melodies are added variations for the pleasure of Friends of the Muses." The instruments mentioned are referenced on the frontispiece: two cherubs are pictured, one playing a pipe organ (possibly with a pedalboard), the other a single-manual harpsichord or clavichord.

Pachelbel wrote a short preface (dated November 20, 1699), in which he dedicated the collection to Dieterich Buxtehude and Ferdinand Tobias Richter and expresses a hope that his eldest son Wilhelm Hieronymus might study with one of them (it is unknown whether this hope was realized). Pachelbel also confesses that "something weightier and more unusual" than this work should have been written for the occasion, apparently feeling that this is not his best work. Pachelbel alludes to the "friendly nature" of Buxtehude and Richter, which might indicate that he knew one of them or both, perhaps through correspondence.

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