By Stephen Brookes • The Washington Post • December 10, 2012

The early 18th century was a great time to be alive, if you happened to love music. Not only was Johann Sebastian Bach churning out one masterpiece after another, but a dozen other top-notch composers — from Handel to Vivaldi to Telemann — were all thriving as well, generating what cellist David Teie of the Eclipse Chamber Orchestra calls a “firestorm” of creative energy.

Johann Sebastian BachThe extraordinary music that resulted was the subject of a fascinating concert on Sunday afternoon by the Eclipse players — a group largely made up of musicians from the National Symphony Orchestra — at the George Washington Masonic Memorial in Alexandria. Narrowing its focus to the concerto grosso form, in which small groups of soloists are pitted against a larger orchestra, the ensemble contrasted Vivaldi’s relatively light, open style with the harmonic complexity and densely woven counterpoint of Bach — and showed both off to elegant advantage.

It’s always a pleasure to hear the NSO players in solo roles, and Vivaldi’s Concerto for Two Flutes in C, RV 533, which opened the program, received a lighthearted and completely charming performance from Carole Bean and Alice Kogan Weinreb, who wove their melodic lines together in a kind of affectionate, playful echoing of each other. Even more satisfying was Bach’s Concerto for Oboe and Violin in C Minor, with Nicholas Stovall and Elisabeth Adkins on oboe and violin, respectively; the two showed how profound and emotionally complex the concerto grosso form could be. Stovall has a gorgeous tone (think chocolate with a little honey in it), and he and Adkins navigated Bach’s tightly argued counterpoint deftly and with convincing authority; a beautiful, captivating performance in every way.

Equally impressive was the orchestra, which played with extraordinary precision and cohesion despite the lack of a conductor. In fact, the only out-of-place note in the afternoon came after intermission, when harpsichordist William Neil switched to the organ for the “Offertoire Sur les Grands Jeux” by Francois Couperin. It’s a masterpiece of the baroque, and Neil brought it off with admirable power. But the heavy sound of the organ felt jarring in this otherwise delicately detailed program, as if an elephant had lumbered into the room and was tearing up the violins.

But things quickly got back on track with Vivaldi’s Concerto for Violin and Cello in B-flat Minor, RV547, thanks to eloquent, thoughtful playing from Teie and violinist Heather LeDoux Green (who seemed to float skyward at times from the sheer beauty of the music). But it may have been the closing work of the afternoon, Bach’s Brandenburg Concerto No. 3 in G, BWV 1048, that was the most intriguing. It’s a constantly shifting, wonderfully protean work where you’re never quite sure which of the nine soloists are in the foreground, and which in the background. The Eclipse players brought it off in a deeply integrated performance, full of subtle nuances and great beauty.