"It's a fun symphony," Craig Curtis tells his WETA listeners, "played by the dogs and guns and strings of the Academy of St. Martin in the Fields." It's Mozart's "Hunting Symphony," and true enough, it features occasional barking and shooting.

Over on WGMS, Dennis Owens, the silver-tongued morning man, glides flawlessly over a terrifyingly T-laden tongue-twister, then tells his audience they have a choice: "Listen to Franz Liszt or say this," and he rips through the twister once more. "Do you want to give that a try or listen to Liszt?" he says with a chuckle. "Boy, you're a bunch of chickens, aren't you?" Up swells the orchestra.

Classical music, once the mainstay of radio, has become medicine that must be coated with candy, cut to bite-size pieces and slipped unnoticed into listeners' ears.

The classics on the radio are in deep trouble in this country. Depending on the city, classical stations may be vanishing from the airwaves, morphing into a new hybrid of classical, jazz and world music, or -- as in Washington -- thriving despite the troubles of America's orchestras and record labels. But even here, where two FM giants and one tiny college station seem committed to the music, surface success masks a looming demographic crisis.

The capital's two major classical outlets -- commercial WGMS at 103.5 FM and public WETA at 90.9 FM -- can boast of huge audiences, loyal listeners and financial success. WGMS, the top-rated classical station in the nation, turns a tidy profit, collecting about $8 million a year from advertisers. WETA, one of the most listened-to public stations in the country, is also the highly influential flagship of National Public Radio. Washington is one of the nation's best markets for classical radio, which nationwide reaches only about 3 percent of the radio audience, but regularly draws more than 7 percent of listeners here.

But executives at both stations admit that to maintain their audiences, they have had to change the music they play and the way they present it. If they are to survive, they say, they must sharply alter the traditional definition of classical radio.

The aging audience for the music and the changing economics of radio are conspiring to cast classical radio's survival in doubt: Last year's federal telecommunications law has unleashed an explosion of station sales, as a handful of companies buy up most big-city stations. Having paid top dollar for their stations, those companies then place unprecedented pressure on radio managers to maximize profits and reach bigger audiences.

Meanwhile, in public radio, declining government funding forces stations to reach ever-broader audiences so they can pull in more listener contributions. In both cases, a fringe format such as classical music becomes ever-less viable -- even if the audience is affluent, educated and loyal.

To save their franchise, classical stations extract short, melodic bits from orchestral works, slip in themes from movies and musical theater and serve up a steady diet of fanfares, overtures, and other light menu items.

"We had to wake up and be aware of our audience," says Dan DeVany, midday announcer and former general manager at WETA. DeVany, like many of his colleagues in classical radio, is a trained musician whose own tastes are sophisticated and eclectic. "We all have our personal tastes," he says, "but we have to put that aside."

DeVany programs for "the middle-of-the-road person, who may have a smattering of knowledge of classical music. But I loathe the idea that you assume people know the music." When an announcer introduces "Symphony Number 3 by Franz Josef Haydn," DeVany says, "I just feel the wall going up with the listener." He'd rather tell the audience, "Here's a symphony, that's it. People don't care; just play the darn thing."

The new consensus among classical programmers is that listeners must be shielded from long works, vocal pieces, 20th-century music, discordant sounds and most anything that is not familiar. It is a belief system that has spread from commercial to public radio, leaving the two virtually indistinguishable.

Indeed, some radio executives argue that public stations -- including WETA here -- have done more than their commercial competitors to dumb down the music, adopting a programming computer model -- called "modal music" -- that classifies every piece by its emotional content, serving up "bright" in the morning and "peaceful" at midday.

"There's Bach and Beethoven we don't play because of the demanding nature of the music," WETA Program Director Craig Curtis says. "Bach's Art of the Fugue' is fantastic music, but it's hard to play on the radio because it just reaches out and demands your attention. There are limits to what our listeners can listen to. Radio is a secondary activity most of the day."

"This is not music for people who understand it," WGMS morning announcer Dennis Owens says. "It is music to be enjoyed. The people who complain when I play Star Wars' are retired, in their living rooms, prepared to be concert-hall entertained. I play music for people who are in their frigging cars, they're agitated by the traffic and they want something to soothe them."

"There are public radio stations that have gone way too far toward Top 40 classical radio," says Tom Voegeli, producer of "Schickele Mix," a public radio program in which composer-comedian Peter Schickele draws from classical, jazz, pop and world music to teach listeners how music works.

Whether the computer model really lures new, younger listeners is questionable. A study by the National Endowment for the Arts last year found that the Americans who most actively supported classical music were born between 1936 and 1945, putting them squarely in their fifties. Neither orchestras nor radio have lured large numbers of the 18-49 crowd.

The average age of a WGMS listener is 52. When a 38-year-old listener called the station's contest line, it was deemed worthy of celebration. Public radio listeners may be a shade younger, but not much. And at WGTS-FM (91.9), the tiny Seventh-Day Adventist college station in Takoma Park, executives have examined listener demographics only twice in the past decade: 10 years ago, the average age was 45. Last year, it was 55.

Even as it has failed to grab younger listeners, the new mode of presenting classics on the air has alienated many music buffs. And some musicians, orchestra executives and critics believe that the way classical radio is headed, the next generation of fans may never develop.

"When you start programming by computer, you're using a sensibility that has a lot more to do with three-minute pop songs," says Melinda Whiting, editor of Symphony, the magazine of the American Symphony Orchestra League. "Classical music is active listening music. It is based on conflict and resolution, tension and relief. When you pull out fragments of a piece, you are losing the meaning of that piece."

Whiting, who occasionally hosts NPR's "Performance Today" and is the voice of St. Louis Symphony Orchestra broadcasts, says the modal music concept is fundamentally flawed. "The greatest music really can't be reduced to a couple of adjectives," she says. "A Beethoven first movement is not just fast and bright.' "

Even inside public radio, the modal music idea is controversial. But it is quickly gaining acolytes as public broadcasters scramble for higher ratings.

"The trend is to very, very limited play lists that programmers think will appeal to the audience," says Voegeli, whose "Schickele Mix" airs Saturdays at 3 p.m. on WETA. "At its worst, this emphasis on audience research seems so antithetical to the idea of public radio as an alternative. But on the other side, public stations were being programmed by auteurs who played what they wanted to play. And stations that have tried to do more adventurous, more eclectic programming have not done well."

"To reach younger listeners, we have to keep the music accessible to people who might just be sampling the station," WGMS Program Director Jim Allison says. "We can't be programming just for the music aficionados."

WETA's Curtis agrees: "It would be possible to push WETA and WGMS apart. We could be the gonzo young classical station, but we've each chosen to be fairly broad and conservative."

Some public radio traditionalists believe the choice between easy mood music and serious programming for the musically savvy is a false dichotomy. They say entertaining programs can attract both novices and the knowledgeable. The proof, they say, is programs such as "Schickele Mix" and NPR's daily "Performance Today," which offers music news, interviews and concert performances of both traditional favorites and the cutting edge of new music. The program is heard on 204 public stations including WETA here (7 -9 weeknights).

In addition to such programs, one Washington station prides itself on playing the music other stations won't. Broadcasting from a Quonset hut on the campus of Columbia Union College in Takoma Park, WGTS is a low-power classical outlet where every work is aired in its entirety, where chamber music is played every day, where the dark sounds of cellos, oboes and even the double bass have not been banished. WGTS -- heard primarily within 15 miles of the campus -- is a throwback to an earlier era of classical radio.

Run almost entirely by current and former Columbia Union students, the station -- operates on a fraction of the budget of the other stations. But WGTS -- which devotes 36 hours a week, from Friday evening to Sunday morning, to religious programming -- has won the hearts of a few thousand dedicated listeners, who contribute the $264,000 it takes to run the station annually. Station manager John Konrad does not subscribe to any ratings service and has never convened a focus group. Neither he nor program director Sharon Kuykendall has any music training, yet their station plays more adventuresome works than the two big classical outlets put together.

"We try to be an alternative to WETA, doing the things they've moved away from," Konrad says, including Sunday concerts from the Phillips Collection and the National Gallery. Yet even WGTS steers clear of contemporary music: "We take into consideration that we are owned by the Seventh-Day Adventist Church," Konrad says, adding that church elders don't dictate programming, but "we wouldn't want to get too far out."

About 460 radio stations across the country play classical music now; 40 of those outlets are commercial, the rest are listener-supported. The number of commercial classical stations has been dropping steadily for decades. What's new is the decline in public stations devoted to the classics.

Once upon a time, almost every station in the nation played classical music. Major networks had their own orchestras. In many European countries, state-supported networks still maintain orchestras, and still devote extensive air time to the most obscure or difficult music -- all without much pressure to reach a mass audience.

In this country, the longstanding stereotype of the classical audience is, for the most part, true. There's a reason commercial classical stations carry ads for Lincoln Town Cars, Lufthansa and Blue Nun: The relatively small classical audience is older and wealthier than rock, rap or pop listeners. The median income of WGMS listeners is $72,500, among the highest of any U.S. radio station.

On the public side of the dial, the classical audience is overwhelmingly white, more affluent than average and more generous than most in giving to public radio.

But public radio's original purpose as an alternative has given way to a marketing strategy -- fed by expensive audience research -- that positions public stations smack in the mainstream of U.S. media, chasing after the same mass audience any other radio station seeks.

The search for listeners has lured stations in different directions. The public classical station in Columbus, Ohio, dropped NPR news to devote itself entirely to the music. Same story in Cincinnati.

In Los Angeles, however, public KUSC halted its experiment with an eclectic mix of jazz, classical and new age music to return to a traditional classical sound. But the city's commercial classical outlet switched to the heavy beat of urban music. And in Philadelphia, the public station quit classical to devote itself exclusively to talk and news. Similar decisions doomed the classics in San Francisco, Houston and San Diego.

"More stations are going to news-talk than the other way around," says Craig Oliver, president of Radio Research Consortium, which tracks public radio audience numbers.

WETA's commitment to the classics remains strong, the station says. But the ratings show that WETA's most popular program, by far, is "All Things Considered," the late afternoon newsmagazine. And in public radio these days, news rules.

"In the '80s, a lot of us who got into public radio because of classical music realized we were working for news stations that happened to play classical music," Curtis says.

Thus was born the modal music experiment, a series of focus groups and listener surveys designed to identify the music that would most appeal to NPR news listeners. The idea, born in Denver, has filtered out to stations across the country, including WETA.

The modal computer model selects music not according to its period, genre or composer, but simply based on how it sounds. If listeners say they like music to be rhythmic or fast, pluck out the movement of a piece that fits the bill.

"We recognize the kinds of sounds and moods our audience likes," Curtis says. "When an NPR news listener says classical music, he or she means something that sounds like a Mozart symphony -- a brighter sound. So we've moved WETA to a little less lush sound, more classical than romantic."

Pieces follow one another because they have similar chord structures. Announcers are not lively personalities, but mellifluous voices that slip in and out barely noticed by the audience. Opera is out because it drives away younger listeners. "We'll play English madrigals or Central European part songs, but not bellowing baritones or shrieking sopranos," Curtis says.

In the 1970s, WETA boasted that its job was to provide the kind of music commercial stations would not play -- the avant-garde, the longer pieces, the 20th-century works.

That thinking is passe now, even though some public stations elsewhere still play edgy new music. Not WETA: "Every time you venture away from an expectation, you blow away part of your audience," Curtis says. He points to a portrait of Bela Bartok pinned to the bulletin board over his desk. "We don't play a lot of Bartok, but he's right up there. We can do more for classical music by taking a very broad approach. As you add different kinds of music, you lessen the appeal of the radio station."

Allison says the 20th-century works he would play "are few and far between. This is a safe city. That kind of thing is too far of a stretch."

Both WETA and WGMS cross-market with the National Symphony Orchestra, and both frequently invite conductor Leonard Slatkin on their air. But no local station would play many of the newer works Slatkin is introducing to Washington audiences.

At WGMS -- the call letters stand for Washington's Good Music Station -- Allison, trained as a pianist, puts aside his own taste to choose music through surveys in which listeners are played snippets of music and serve up their opinions by turning a little dial on a console.

As a result, what WGMS plays is limited to three periods -- baroque, classical and romantic. Familiar pieces rule. Vocals, both big stations agree, are what WGMS General Manager Catherine Meloy calls "a major station-changer."

The big difference between WGMS and WETA is personality. The commercial station encourages announcers to tell stories, to get excited about the music. "People come to radio to be entertained above and beyond the music," Meloy says. "They come for the personalities."

With Owens in the morning, the infectiously charming 29-year-old Diana Hollander middays, John Chester afternoons and James Bartel in the evening, WGMS keeps the station in the foreground with wordplay, jokes, contests, even illuminating comments about the music.

Despite the different styles, WETA and WGMS have about the same size audiences, and surveys indicate many listeners switch back and forth between the two.

To find new listeners, WETA's DeVany believes classical music, like pop music before it, will come to depend more on the visual, building on the tradition of Disney's "Fantasia" to win new audiences. The violinist Gil Shaham's recent and hugely successful marketing of his video of Vivaldi's "The Four Seasons" on, of all places, the Weather Channel, will lead to other such experiments, all of which will help the classics on radio, he says.

But radio -- the only medium that regularly introduces the classics to listeners without a fee -- must find a way to play its role without wasting energy chasing audiences that may never respond. Classical radio thrives where programmers accept that they serve a small but loyal audience.

"The future is not as dire as people are saying," DeVany says. "A culture this rich isn't going to go away." A Musical Sampler

Washington's classical radio stations offer three different approaches to the music. Especially in morning drive time, WETA and WGMS favor short, bright excerpts from longer works, with lots of fanfares and overtures. WGMS further lightens the morning with snatches of movie theme music and other novelties. WGTS sticks with its policy of running full pieces, though it, too, steers clear of heavy works in the early morning.

Middays provide a better comparison of the styles of music each station favors. Here are sample works each station played on a recent weekday between 10 a.m. and 2 p.m.:

WETA

Schubert: Symphony No. 5 in B-flat, D. 485

Herbert: Cello Concerto No. 2 in E, Op. 30

Handel: "Water Music"

Bizet: Symphony in C

WGMS

Bernstein: Overture to "Candide"

Bach: Orchestral Suite No. 4

Gluck: Dance of the Blessed Spirits from "Orfeo ed Euridice"

Saint-Saens: Introduction and Rondo Capriccioso for Violin and Orchestra

Beethoven: Piano Concerto No. 3

Falla: Ritual Fire Dance from "El Amor Brujo"

Rossini: Overture to "The Barber of Seville"

WGTS

Mercadante: Flute Concerto in E Minor

Rachmaninoff: "Trio Elegiaque," Op. 9

Britten: Cello Symphony

Ippolitov-Ivanov: Georgian War March

Vivaldi: Cello Sonata No. 4 in B-flat

CAPTION: WGMS's Jim Allison, left, and Dennis Owens, who says, "This is not music for people who understand it."

CAPTION: The spirit of Beethoven presides over Sharon Kuykendall and John Konrad of WGTS, a throwback to an earlier era.

CAPTION: Morning show host Dennis Owens in the WGMS studio: "I play music for people who . . . want something to soothe them."

CAPTION: WETA deejay Dan DeVany and Program Director Craig Curtis, who says, "There are limits to what our listeners can listen to."

CAPTION: Program Director Sharon Kuykendall and station manager John Konrad of WGTS, see their station as an alternative to WETA.

CAPTION: WETA's Dan DeVany and Craig Curtis in the station's music library.