Historical performance recordings and programs established in a specific time and place, or among specific musicians, have become commonplace. Yet those exploring the musical circle of a monarch are not so common, even though the king in question here, Frederick the Great of Prussia, inspired and provided the theme for one of Bach's most famous compositions, the Ricercar from the "Musical Offering, BWV 1079." That work opens this double album, which also includes chamber works from other composers associated with Frederick. It may seem to be the kind of release that appeals most to listeners whose pulse quickens when they hear the words historical performance, but the album has enjoyed commercial success for several reasons. There is the presence of several unfamiliar composers, all landing near the increasingly attractive dividing line between Baroque and Classical. Johann Joachim Quantz and the Graun brothers, Carl and Johann, show up mostly on albums devoted to Bach, while Johann Gottfried Müthel and Franz Benda are even rarer. The real find here, and also entirely unfamiliar, is the "Andantino con VII Variazioni in G major, Op. 17" by Carl Friedrich Christian Fasch, son of Johann Friedrich Fasch, himself known mostly through Maurice André's advocacy of a single trumpet concerto. Carl Friedrich Christian served for a time as deputy to Carl Philipp Emanuel Bach, and from this variation set it would seem as though some of his bosses iconoclastic ideas rubbed off. This work is unlike any other variation set of the time, with daring moves in both harmony and texture; it's actually a good deal more unorthodox than the flute-violin duet of C.P.E. which closes the album. Another draw for this release, exemplified in the Fasch work, is the variety of instrumentation; this work and the Müthel "sonata" use a clavichord, which is manifestly appropriate (Frederick the Great certainly owned one or more) and rarely done. Finally, there are the strong performances by the Baroque chamber group Florilegium, which includes some cutting-edge players (check out the very reedy violin played by Bojan Cicic in several works). Florilegium cultivates a warm chamber music sound that would have been even more intimate had the musicians not been placed in an inappropriate church venue. Recommended for fans of the late Baroque.