The vitality of the musical life of a community is measured more by the extent of individual involvement in music-making than by the number of professional concerts that are presented. By this measure, the Washington area is rich indeed.

The city is blessed with a number of excellent amateur choral groups, the thriving D.C. Youth Orchestra program, several pages of listings in the Amateur Chamber Players Directory and, not the least, the D.C. Community Orchestra, which performed at the Takoma Theater Sunday.

A community orchestra exists primarily for the players, and this one is unusually fortunate to have as a conductor Dingwall Fleary, who is not only thoroughly professional and a first-rate musician, but also an orchestra builder, a teacher who can draw the best from his musicians. He led the orchestra with splendid clarity and, throughout, chose and maintained excellent energetic tempos that made no concessions at all to the difficulties of the music.

Fleary chose a program that challenged his forces but did not defeat them. They were at their best in the fugue of the second movement of Bizet's Symphony No. 1, where careful rehearsing and excellent concentration produced a unanimity of phrasing and intonation.

Norman Middleton was the soloist in the Haydn Oboe Concerto, playing with well-focused tone and particularly agile and nicely timed ornamentation. The concert opened with the Beethoven "Coriolan" overture. -- Joan Reinthaler Canterbury Cathedral Choir

The Canterbury Cathedral Choir went from William Byrd to William Walton in a splendidly executed concert Sunday evening at Washington Cathedral, in its first North American tour. Conductor Allan Wicks carefully emphasized dynamic nuances, shaping crescendos while balancing men's and boys' voices in Robert Parsons' "Ave Maria." That balance was equally evident in Byrd's "Vigilate" and throughout the program.

The choir gracefully interwove polyphonic voicings in Antonio Lotti's "Crucifixus," but had slight intonation problems in the following work, Brahms' "Wenn ein Starker Gewappneter."

Organist Michael Harris explored fugal intricacies and timbral riches in Bach's Prelude and Fugue in C Major, BWV 545, and joined the singers in Walton's glorious "Te Deum laudamus." The cathedral itself was one of the performers, as when it held the last hushed notes of Poulenc's "Tenebrae factae sunt" in the softest embrace. -- Sunil Freeman Washington Chamber Society

Debussy would have turned 125 this year, and the Washington Chamber Society marked the anniversary of his birth Saturday night with a concert devoted to his works at Wesley United Methodist Church. The evening had a weak start but concluded with expert music-making.

The composer's only string quartet, and oddly the only piece to bear an opus number (Op. 10), was ground-breaking in 1893, and it remains a complex vehicle even for today's performers. Violinists George Marsh and Sally McLain, violist Denise Wilkinson and cellist David Premo offered a top-flight reading, giving textural matters excellent consideration throughout. The first movement's multitude of tempos, often a stumbling block, and the whole work's subtle motivic treatment emerged with clarity, control and vitality.

Wilkinson, joined by flutist Karen Johnson-Smith and harpist Caroline Gregg, opened with the Sonata for Flute, Viola and Harp, a work whose bare detail in the ensemble writing needs more integration and balance than it received. The short "Syrinx," for solo flute, might have used a gentler approach, but intonation was quite secure.

Ensemble work was fine in "Danses Sacre'e et Profane," for harp and string quartet, where delicate coloring and an airy spirit added to the elegant performance. -- Kate Rivers Leningrad Dixieland Jazz Band The capacity Baird Auditorium audience made some noise Sunday night when the band failed to show on time. After insistent, though polite, clapping, eight guys wearing sedate matching gray suits came out swinging.

For the next two hours, the Leningrad Dixieland Jazz Band captivated everyone with New Orleans classics, blues and Gershwin played red-hot and Russified.

The lineup is traditional: clarinet, alto sax, trombone, trumpet, piano, banjo, string bass and drums. Saxophonist Oleg Kuvaitsev's arrangements put a fresh gloss on these venerable tunes, showing that the musicians have not memorized old recordings, but have made their own interpretations.

The only creaky element was the singing, which humorously removed several numbers from their American context. Yet when the band played "I Got Rhythm," no one questioned its validity. The audience was too preoccupied, tapping and nodding to the music.

-- Charles McCardell