While prices for almost everything continue to rise, the Washington Performing Arts Society, which brings the most prestigious names in music and dance to the Kennedy Center every year, has reduced prices for its 1982-83 Kennedy Center season by about 25 percent.

"I don't think any other city has this kind of opportunity," said Jan Kendall, assistant manager and director of public relations at WPAS. "Somebody has to make a start somewhere. Otherwise we have empty seats. That's bad for the artists, it's bad for everyone."

The new season, which opens with Yves Montand next Tuesday, is a heady mix of names, including the Dance Theatre of Harlem, Metropolitan Opera soprano Kiri Te Kanawa in her first Washington recital (singing "Let the Bright Seraphim" from Handel's "Samson," which she sang at the royal wedding last year), a Festival of the Nile with 40 Egyptian performers, the Chieftains with Irish traditional music, and the London, Vienna and New York symphony orchestras.

"Last year it was $15 a seat for the good seats for, say, Isaac Stern," Kendall said. This year, it works out to $11.80 a seat. "It's very frightening to put on a series like this. We lose money on most of the concerts anyway, and it makes it more frightening to have an empty seat. Our expenses are exactly the same; the artists and technicians are being paid the same, so one unsold ticket is very expensive."

Kendall said WPAS tried an innovative marketing technique this year to fill those empty seats. In addition to its "sampler," in which patrons choose five performances from a list of 36 artists, including orchestra and chamber music, recitals, pops concerts and dance, "we grouped the concerts together," Kendall said. "For example, the 'Keyboards' series. Pianists Andre'-Michel Schub and Cecil Licad are two excellent youngsters, but their names wouldn't sell on their own. So we grouped them in a series with the two older, more established names, Alicia De Larrocha and Rudolf Serkin. This way, people will come out of Licad's concert saying, 'I'm glad I saw that girl.' "

Similar series packages are available for concertos, chamber music, "Stars of the Opera," "Dance America" and the annual Handel Festival, at prices ranging from $9 to $11.80 a seat.