Back to Bach: We are approaching the 250th anniversary of the death of Johann Sebastian Bach (1685-1750), and you can expect to hear a lot of his music between now and the actual anniversary next July.

In Washington the observances will begin Oct. 4 with a performance of his Mass in B Minor at the Kennedy Center. This event will be part of another anniversary celebration--the centennial of the Bach Choir of Bethlehem, Pa., the oldest American ensemble specializing in the composer's music. It will be the first performance in Washington by the Bach Choir since 1925, when it sang for Calvin Coolidge at the White House.

One happy participant in this performance will be a Washingtonian: soprano Rosa Lamoreaux, who is a frequent soloist with the Bach Choir. Like a number of Bach enthusiasts from the Washington area, she usually commutes up to Bethlehem (more than 150 miles) for the choir's performances. The Kennedy Center may lack some of the weathered charm of the chapel at Lehigh University where the group usually performs, but those who have driven from here to Bethlehem through miles of road construction will appreciate the convenience.

In the history of the recording industry, no label before now has issued a complete edition of all Bach's surviving works (a fraction of what he actually wrote, thanks to the carelessness of his heirs). Suddenly this year, for the upcoming anniversary, record collectors will be able to choose from three complete sets, each running to approximately 150 CDs and including more than 1,000 works. Perhaps more sensibly, one can mix and match, maybe even omit a few selections and possibly get more than one recording of a favorite piece. "The Art of Fugue," for example, will never have a single definitive recording. Bach's manuscript does not specify any instruments, and the music can be performed credibly by orchestras, chamber groups and various kinds of keyboards, including synthesizer. More than any other composer's music, Bach's remains special, and recognizably Bach, in almost any kind of transcription--even in jazz treatments.

The complete sets (all including reissues, some with reduced prices) feature the work of many respected interpreters, but they vary in their stylistic approaches. The one issued by Hanssler Verlag (a German label distributed in this country by Collegium Records) is solidly traditional in style, using German soloists and ensembles under the general supervision of conductor and organist Helmuth Rilling, whose achievements include a complete recording of Bach's cantatas. Harmonia Mundi's elegant set reflects the label's French origins and its involvement with performances on period instruments. Its roster of performers is international, including Philippe Herreweghe and La Chapelle Royale, Charles Medlam and London Baroque, and organist Andrew Manze. The Teldec set, eclectic and sometimes stylistically daring, includes the work of organist Ton Koopman, Nicolaus Harnoncourt and the Concentus Musicus of Vienna.

More modest but worth noting are the recordings of individual works or groups of works that are beginning to appear and can be expected to continue arriving in a long crescendo until next summer. Issued by Dorian Records (93183, two CDs with libretto) in time for the Bach Choir's Kennedy Center debut, if a few months before its usual season, is Bach's "Christmas Oratorio"--actually a cycle of six cantatas for the season between Christmas and Epiphany. The Bach Choir gave this work its first American performance in Bethlehem on May 23, 1901. It also gave the first American performances of the Mass in B Minor (which has also been recorded by Dorian) and many other choral works. It is a large chorus by current standards of musicological correctness--more than 100 voices--but under the direction of conductor Greg Funfgeld it sings with a lightness and clarity usually associated with smaller groups.

Often found musicologically incorrect but also musically irresistible were the piano interpretations of Bach's music by Glenn Gould. These are already familiar to most music lovers who might want to collect them, but a few items have been repackaged on a CD that is presented as a tribute to the pianist but also pays a fine tribute to Bach: "Glenn Gould at the Movies" (Sony 66531). Gould's recordings have been used in the soundtracks of several films, including "Slaughterhouse-Five" and "Thirty-Two Short Films About Glenn Gould," and they are recycled into this collection. Bach is not the only composer represented--there are also selections by Richard Strauss, Brahms, Sibelius and Scriabin--but the Bach pieces have a special resonance.

Perhaps the anniversary's most unusual tribute to Bach is "Absolute Joy: Lives and Times of Angels" (Albany 327, with texts) by Anthony Newman--an oratorio that neatly balances familiarity (in its musical style) and originality (in its choice of texts and subject matter). Composed by one of our era's outstanding performers of Bach's keyboard music, it uses texts on angels from the Bible and other sources (Saint Augustine, Milton, Shakespeare). The music is as thoroughly imbued with the style and spirit of Bach as a 20th-century composition can be. Newman, who says he is "projecting a new career as composer," has a contract with Albany Records for three more recordings. Still to be issued are two symphonies, a disc that he describes as "a Bach 2000 tribute . . . my own works modeled after his" and an opera, "Nicole and the Trial of the Century," based on the trial of O.J. Simpson.

Coming Events: The Philadelphia Orchestra will devote its entire 100th anniversary season, opening Wednesday night, to performing music composed in the century of its existence--"especially," as its announcement says, "music that the orchestra has made famous."

Hesperus, a Washington ensemble that explores the connections between early music and various folk idioms (blues, Appalachian and the like), has returned from touring in Europe and established a residency program in Arlington. Its first concert in the program, Oct. 3 at the Spectrum in Rosslyn, will be a program of Renaissance and baroque music, highlighted by a work of Marin Marais (you may remember him from the movie "Tous les Matins du Monde"), using music and spoken narrative to describe his kidney stone operation.

Music Alive: The American Symphony Orchestra League and Meet the Composer are launching a joint program called "Music Alive," which will put composers in residence with American orchestras for periods of two to eight weeks while the orchestra programs their music. Orchestras and composers wishing to apply for the program have an Oct. 1 deadline; for information, phone Heather Hitchens at 212-787-3601, ext. 111, or Jesse Rosen at 212-262-5161, ext. 240.

Music on the Tube: The gala opening night of the New York Philharmonic's season will be telecast Thursday on PBS's "Live From Lincoln Center." Kurt Masur will conduct Tchaikovsky's Symphony No. 5 and Dvorak's Cello Concerto with Mstislav Rostropovich as soloist. Program notes and other information are available on the program's Web page, www.livefromlincolncenter.org