There are probably more people playing the recorder today than there were throughout the Middle Ages and the Renaissance, when the simple wooden flute was in its heyday. But not many can bring out the recorder's bird-like agility and haunting tone as gracefully as the Folger Consort, who will be heard on radio and television at 9 tonight, simulcast on WETA-TV (Channel 26) and FM (90.9).

The program, "He, Trez Doulz Rossignol" ("Sweet Pretty Nightingale"), taped Monday night at the Folger Shakespeare Library, focuses heavily though not exclusively on the recorder. Solos, including some virtuoso bird imitations, are handled by the Consort's regular recorder player, Scott Reiss, but the group brought in three guest artists for the occasion.

In some numbers, which range from the 14th to the 16th century, there are as many as five recorder players performing on instruments that range from the tiny, shrill sopranino to a double-brass recorder about eight feet tall. Other unusual instruments include the racket: Made of wood, it looks something like a tin can with a handle, into which the performer blows.

In the Elizabethan atmosphere of the Folger's theater, where the concert was taped, the presence of the television cameras provided a distracting anachronism for the live audience. But this does not show in the telecast, in which the cameras avoid shooting one another except for an occasional blurred, fleeting glance, and in which someone in the audience is occasionally caught shielding his eyes from the unusual bright lights. In compensation, television offers its viewers some perspectives unavailable to a live audience, such as closeups on the fingers of a lutenist or recorder-player in action.

The music is graceful and charming -- particularly the singing of soprano Ann Monoyios -- and the program should bring to the attention of a wider audience a local group that is rapidly moving into international front rank of organizations specializing in early music.