When you think of great, free music in a historic venue, naturally, you think: United States Air Force.

Well, maybe not. But maybe you should.

The Air Force Band, extremely accomplished in its own right, launches its acclaimed Guest Artist Series at Constitution Hall on Feb. 6 with a performance by Chaka Khan. The headliner performances continue every Sunday afternoon through March (with the exception of March 12) including the likes of Keiko Matsui (Feb. 13) and Patti Page (March 5).

This annual bonanza has been coming our way since 1966--the secret is clearly out of the bag by now. Capacity crowds will be cramming the 3,200-seat auditorium, and with no tickets to guarantee entrance, it is wise to arrive before 2 p.m., when the doors open for the 3 p.m. performance. (Note that special seating is reserved for those in wheelchairs.)

Constitution Hall was designed for the National Society of the Daughters of the American Revolution in the 1920s by John Russell Pope, who also designed the west wing of the National Gallery of Art, the Jefferson Memorial and the National Archives Building. It is eye-popping neoclassical on the outside, all Alabama limestone and massive columns, and recently redone inside, with the kind of seating comfortable enough for a snooze, if the music weren't as good as it is.

For you history buffs, it is worth observing that the building was the center of a civil rights crisis when use of the hall was denied to African American singer Marian Anderson in 1939 and Eleanor Roosevelt resigned her DAR membership in protest.

Constitution Hall is at 311 18th St. NW. For the complete concert schedule, consult the Web address, http://www.bolling.af.mil/band, or check the recording at 202-767-5658. You want to talk to a live human being (silly you)? Call 202-767-4310.

--Margaret L. Welsh, Oakton

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