ON THE GO WITH LUKAS FOSS

Lukas Foss, still apparently hyperactive and philosophical at 64, delivers aphorisms as lightly as some people drink coffee. On the phone from New York, he quips offhandedly, on the subject of musicians who, like him, do more than one thing well: “If you have two lives, you have no life.”

As one who has earned considerable notoriety for his work as composer, pianist, conductor and raconteur for at least 40 years, Foss ought to know whereof he speaks. Still, one hasn’t noticed any slowing down in any of the conductor-composer’s musical functions.

“Oh, yes,” he rushes to reassure, “I gave up the piano. Not the playing, just the practicing. The piano had to go.”

Even so, the music director of the Brooklyn Philharmonic--an orchestra that gives 60 performances a year--has kept composing high on his list of activities. Next Sunday, for instance, he will participate in the Los Angeles premiere of his latest work, “Tashi,” written for the ensemble, Tashi, with which Foss is touring--this week.

“But I won’t be able to enjoy the tour,” Foss laments, “Because I have a deadline for another piece I am writing, and the deadline is--March 1!”

“Tashi”--the work, not the group--received its world premiere Tuesday night at Kennedy Center in Washington. Later last week it was heard in New York, Boston and Kansas City. Tashi, the group, plays it in Chicago, Urbana, Ill., and San Francisco this week before bringing it to Wadsworth Theater in Westwood.

“It’s not a long piece--I would say it’s under 20 minutes, though it has four movements. But I agonized over the writing.” What made the composition of it difficult?

“I don’t know what made it so hard. Psychological reasons, no doubt--perhaps the fact that I was writing for friends.” The players on this tour, besides pianist Foss, are violinists Ida Kavafian and Theodore Arm, clarinetist Richard Stoltzman, violist Steven Tenenbom and cellist Fred Sherry.

According to Foss, he worked on the new piece “every day for four months, finishing on the first day of fall, last Sept. 21.” And now, after a couple of private tryouts--”We gave what we called ‘the world preview’ the other night,” the composer says--he feels all the hard work was worthwhile.

“I am my own worst critic, so I can say it: It’s not so bad.”

How would he describe the idiom of the piece?

“Well, first, I must say, many people get confused. They mistake style for technique, and those are not the same thing. My style remains the same, or slowly changing, or whatever, though I may use different techniques in every work I write.

“I am not my own connoisseur, so this is not so easy to say. Like Stravinsky and Mozart, and many others, I delve into different techniques. The techniques in this new work are several. There is 12-tone writing, even moments of ‘chance,’ though very controlled chance. I would say it combines my former self with my experimental self.”

The matinee performance, next Sunday at 4, will be only one of several activities Foss plans while here. As co-director of the Los Angeles Philharmonic Institute, meeting at UCLA this summer, he will spend all day Saturday hearing auditions for the Institute Orchestra.

MORE COMPOSERS-CONDUCTORS: In alphabetical order, John Harbison, Leon Kirchner, William Kraft and Andre Previn will be the conductors at the next concert by the Los Angeles Philharmonic New Music Group, at 8 p.m. Monday in Japan America Theatre. The concert, “Webern and After: Music by Composer-Conductors,” offers Webern’s Concerto for Nine Instruments, Esa-Pekka Salonen’s “YTA 1,” Kirchner’s “Music for Twelve,” Kraft’s “Melange” and Previn’s “Triolet,” the last three to be conducted by their composers.

AND OTHER PEOPLE: Theo Alcantara, music director of the Phoenix Symphony, has been appointed principal conductor at Pittsburgh Opera for the next two seasons, 1987-89. In that post, Alcantara will lead at least two productions a year for the Pennsylvania company, it was announced by Tito Capobianco, general director of the opera. Alcantara will retain his Arizona post. . . .

To celebrate early his 60th birthday, which takes place March 27, cellist Mstislav Rostropovich will this week appear as soloist with the Boston Symphony. Thursday and Friday, in Symphony Hall in Boston, the program lists Boccherini’s Concerto in D, Strauss’ “Don Quixote” and Prokofiev’s Symphony-Concerto. Saturday night the agenda comprises cello concertos by Vivaldi, Lutoslawski and Dvorak. Seiji Ozawa, music director of the orchestra, will conduct all three performances. . . .

R. Lawrence Kirkegaard & Associates has been retained by the San Francisco Symphony as acoustical consultants “in an effort to improve the acoustical qualities” of Davies Hall, the orchestra’s resident hall, “particularly with respect to conditions on stage,” according to a spokesman for the orchestra. Herbert Blomstedt, music director of the ensemble, “has made this project a first priority.” . . .

“Louis Moyse and Friends” brings the French composer, flutist and pianist to Cal State Long Beach at 8 tonight for a program of his own music. Among Moyse’s colleagues at this performance will be the Southern California Flute Orchestra.