Imaginative British composer has a flair for the dramatic

With the death of Sir Michael Tippett in 1998, Sir Harrison Birtwistle and Sir Peter Maxwell Davies became Britain's senior knights of music.

It's a little early to hail Birtwistle and Maxwell Davies as old masters; each is only 70 and still highly active. From the beginning each was a vigorously antiestablishment figure -- a shocked Benjamin Britten walked out of the premiere of Birtwistle's opera ''Punch and Judy" in 1968 -- and neither has exactly been domesticated yet.

Maxwell Davies has been a frequent visitor to Boston, and his music is often performed here. Birtwistle's music remains relatively unfamiliar to local audiences despite intermittent efforts by Collage New Music, Boston Musica Viva, and the Tanglewood Festival of Contemporary Music.

Birtwistle's only previous visit to Boston was on a fishing trip, but this semester he is in residence at Harvard University, where his presence will be celebrated in the city's first all-Birtwistle concert Friday in Paine Hall.

And there's more to come. In April, Christoph von Dohnanyi will lead the Boston Symphony Orchestra in Birtwistle's ''expressive nocturne" ''The Shadow of Night." Next summer John Harbison has programmed a major Birtwistle work for the Tanglewood Festival of Contemporary Music, and the BSO has commissioned a new work for 2008.

Birtwistle has flyaway, wizardlike white hair and a puckish smile; his personality is delightful but elusive. ''Acting costs you extra," he instructs a photographer who is trying to take a portrait. He answers questions politely but lets you know when they don't interest him; he'd rather ask you things, like what you think of poet Jorie Graham or where the good restaurants are. Everything he says is unpredictable yet directional, and in that respect, like his music.

Over a long career, Birtwistle's music has undergone change and development, but certain characteristics are unchanging -- a bristling, forward-thrusting energy as the music moves through complex labyrinths toward its destination; a personal and craggy harmonic language; and an engagement with the large and lasting issues embodied in myths. Most of his operas (''The Mask of Orpheus," ''Gawain," the forthcoming ''The Minotaur") are about myths or collisions of myths. In ''The Second Mrs. Kong" (1994), for example, King Kong goes looking for Vermeer's girl with the pearl earring.

Friday's concert features a selection of pieces from throughout Birtwistle's career. The early ''Verses" for clarinet and piano was the second piece he wrote, back when he was still a teenager, in Wiltshire, where he now makes his home after living in London, Scotland, and France. There is also a selection of his ''Orpheus Elegies" -- he wrote 26 of them and says, ''They are rather like musical postcards."

The program also includes ''Nenia: The Death of Orpheus," for soprano, three bass clarinets, percussion, and piano, written about 20 years ago, and ''Harrison's Clocks," a big, virtuoso blowout for solo piano. The piece comes from Birtwistle's fascination with the maritime clocks built by John Harrison in the 18th century that made it possible for the first time to measure longitude accurately; ''Longitude" was the title of the 2002 movie about Harrison.

''It is music about mechanisms," Birtwistle says, ''and about the divisions of time. And because of his name, I thought it was a particularly appropriate piece for me to write."

Beginning in 1975, he spent a decade as music director of the National Theatre in London; his music for the original stage production of Peter Shaffer's ''Amadeus" -- music of Mozart as heard through the distorting brain of his jealous rival, Antonio Salieri -- is familiar to people who may not recognize Birtwistle's name.

In that period he composed music for seven plays by Shakespeare, and, he notes ruefully, a five-hour score for a celebrated production of ''The Oresteia" that has since vanished; no one knows what happened to the score and parts.

The composer says he's been around theater all his life, playing clarinet in school and in professional productions of pantomimes, vaudeville, Gilbert & Sullivan, and ''worse things than that." He's written only one film score, for Sidney Lumet's 1973 ''The Offence," but has resisted other invitations.

''Beware of composers who conduct or who decide to write film music," he says. ''It means they really don't want to write music."

Some admirers of Birtwistle's music feel that a theatrical impulse is central to all of it. Richard Pittman of Boston Musica Viva led a production of Birtwistle's chamber opera ''Down by the Greenwood Side" here and later conducted a radio production in England.

''There is a tremendous imagination at work in his music, and I find it is a dramatic imagination, even in his purely instrumental and chamber-music pieces," Pittman says.

Composer John Harbison, who has scheduled a major Birtwistle work for next summer's festival of contemporary music at Tanglewood, agrees, and says, ''I think Birtwistle has written a lot of very strongly imagined and highly articulate music, written with a lot of elan and bravado -- but not too much attitude. An almost surly conviction carries his pieces very far."

''I used to say that I wish I'd done my work at the National Theatre when I was a younger man," Birtwistle says. ''But I'm glad I did it when I did -- it taught me to be impractical. It is a big mistake to think practically all the time -- in the theater, and in the opera, you can do anything."

Maxwell Davies and Birtwistle were staunch allies in their youth, but their paths parted in 1970. Their only meeting since was at a BBC concert in 1999. On that occasion, Birtwistle recalled, ''We were going to change the whole musical world, and as much of the rest of it as possible." And Maxwell Davies characterized the relationship of Birtwistle's music to tradition by comparing it to ''a statue that has just been exploded -- it is all still there, but flying off in pieces."

Asked about this observation, Birtwistle did not remember it, and felt it accurately described only some of his work. But he did offer an interesting take on the most controversial major musical development of the 20th century, Arnold Schoenberg's serial method of composition.

''What happened with musical serialism," Birtwistle observes, ''was a little like what happened with cubism in painting at the beginning of the century. It was a natural development, but of its time, and not a particularly attractive way of painting pictures. But it changed our way of looking at everything, and it opened doors to all sorts of other things."

Birtwistle feels that musicians are now past the controversies, entrenched positions, and battle lines that made life so difficult for composers of his generation.

''Now you can do anything you like," he says. ''It is not a question of the technique you choose for writing music, but of what you choose to do with it."