One of Washington’s musical treasures is the Washington Bach Consort, a group of singers and instrumentalists directed by J. Reilly Lewis. The group began, in 1977, with local musicians who were devoted to the performance of the works of Johann Sebastian Bach. After three European concert tours, beginning in the 1980s, and countless critically praised concerts culminating in a landmark appearance at the Library of Congress last April, the WBC has become an institution, recognized far beyond the boundries of the District of Columbia. Over that long history, who knows how many times J. Reilly Lewis has conducted the work that is, in our opinion, the summa of Bach’s choral compositions, the Mass in B Minor, BWV 232. Enough times, to be sure, that when leading his group last night at Strathmore, he conducted without the aid of a score. However, there was nothing routine about this performance, because Lewis and his musicians try to make something new each time they perform a work by Bach, even this most familiar work.

The Consort enjoys the attention of a devoted audience, sometimes bordering on the overzealous side of Bachophilia (a necessary quality behind the desire to subscribe to an entire season of mostly Bach’s music), and they were out in force for this appearance at Strathmore. While most of the seats were filled, with a few empty places in the expensive front section, it struck us, even in Row F, that the rarefied WBC sound is perhaps better served by a more resonant church or a smaller hall (the Coolidge Auditorium at the Library of Congress was ideal, as it is for most chamber groups) than the more cavernous hall at Strathmore. We heard everything, but the acoustic seemed to swallow some of the edges. It’s the start of a new season, which means that there were some new faces in the chorus, and one striking absence. Although the group’s Web site still lists Gisèle Becker as Assistant Conductor, she was missing from the soprano section and her name was not mentioned in the program. We don’t want to jump to conclusions, but for a few years now she has been directing her own group, the Cantate Chamber Singers, and this could be the final parting of the ways between Reilly and Gigi. If so, an era has ended.