As more radio stations turn to test marketing, less diversity in jazz is heard.

Nearly every format on the radio dial--from country to classical--now relies on test marketing before any music crackles over their airwaves. But the use of so-called "research" hasn''t stirred up as much acrimony in any format as it has in Smooth Jazz, the much maligned world of sugar-coated synthesizers and static drum machine grooves that conjure images of sunsets at Point Lobos.

Here''s how it works:

About 100 people gather in a hotel ballroom. Each cradles a little remote control box in their hands with a dial. Music plays over a speaker system in 10-second sound bites. Occasionally, it''s longer.12 seconds, maybe 15. The participants listen to about 600 sound bites in 2 1/2 hours. They turn the dial one way if they like the song, the other way if they loathe it. The scores range from zero to 100. A score of 70 or better means airplay is likely. Below 70 and it''s history.

In a nearby room, radio station officials gather with consultants from Princeton, N.J.-based Broadcast Architecture, whose test has elevated elevator music into a multi-million dollar format. They stare at a video monitor with lines that dance across its screen. Consultants call it the EKG. The lines are the listeners'' "real-time" reactions to the sound bites, grouped by demographics: avid listeners, part-time listeners, men, women, age, ethnicities. The lines show when squealing saxophones break the mood, solos drone on too long, and listeners are ready to change stations.

When the test ends, the consultants assemble the data and compile a list of songs for airplay. The winners include Sade, Simply Red, George Benson, Boney James and Kenny G (among others).

It''s not news that jazz critics and purists condemn Smooth Jazz as an affront to the legacy of Louis Armstrong, Duke Ellington and Charlie Parker. But that''s not the point here. At issue is the use of testing--especially when you notice who''s flunking the test. Some of the jazz world''s most cutting-edge artists--Pat Metheny, the Yellowjackets, Andy Narell, Chick Corea, to name a few--have all but vanished from the airwaves. These artists often fall between the cracks of so-called mainstream jazz and hard fusion or soft "smooth" jazz. Ironically, they were among the eclectic group of artists that defined this format when it emerged (albeit, nameless) some 11 years ago.

The musicians, joined by their managers, record labels and promotional people, assail the tests as unfair--especially in the face of declining record sales.

Coupled with the Telecommunications Act of 1996 (which deregulated the industry and allowed for ownership of multiple radio stations in the same market), test marketing is blamed for creating a bland radio format that sounds no different in Seattle than it does in San Francisco: 24 hours of Kenny G--and saccharine jazz-lite imitators--with some oldies and current urban pop vocals thrown in for spice.

Broadcast Architecture CEO Frank Cody and the program directors from his client stations defend testing. They say it''s the only way to promote jazz to the masses, keep listeners and sell advertising in markets that now compete with other radio formats, cable television and the Internet.

Fairly or unfairly, critics say Broadcast Architecture, or BA for short, wields too much power, a charge that Cody and others dismiss as sour grapes. (BA isn''t the only consultant on the scene but unquestionably the most successful.) Pass the test, get on BA''s recommended airplay list, delivered weekly to its 26 client stations, nine in the top 10 radio markets nationwide. Weekly trade papers report BA''s decisions, and non-client stations follow its lead. If BA says jump, critics assert, America''s Smooth Jazz format collectively asks, how high?

To paraphrase one Bay Area musician, if BA gives your song a thumbs up, nationwide airplay is guaranteed--thumbs down and it''s time to take up plumbing.

"If it doesn''t fit into the format, it doesn''t get played," drummer Dave Weckl says peevishly. "It''s a joke." Chick Corea''s drummer for seven years, Weckl is now launching a career as a bandleader but says it''s impossible to get airplay for his newest record, Rhythm of the Soul.

Guitar icon Metheny, who fronts a trio at the Monterey Jazz Festival on Sunday, agrees. Metheny packs large theaters to SRO attendance but airplay eludes him. Why? He doesn''t test well, DJs tell him. Several older songs, such as "James" from 1982''s Offramp, still get played, but program directors edit out the solos.

"I''m really at the point where I''d rather they just didn''t play any of our music than do what they do," says the multiple Grammy winner. "On the other hand, because we are in an era where there are so few opportunities to be heard, I can''t say, ''Go away.'' We actually need every bit of exposure we can get. I''m not going to lie about it. It''s a matter of survival for us."

Equally ambivalent are Yellowjackets co-founders Russell Ferrante and Jimmy Haslip, who bear no animosity towards BA or consultants. "Mile High," from the group''s 1984 album, Four Corners, still gets played on some stations in so-called "heavy rotation," about 35 spins a week. But now DJs privately apologize for not playing anything from the group''s last five albums, all featuring radio friendly cuts, Haslip says.

Several Bay Area musicians, some established, others trying to climb out of the trenches, tell similar stories. One complained his music used to top playlists in The Gavin Report, an industry weekly that tallies the number of spins at radio stations each week. Today, his music can''t be heard anymore.

Another musician is a producer, whose clients only ask how to write songs that pass BA''s test. An artist himself, he released a vocal record a year ago. Some 15 stations, including San Francisco''s KKSF, a BA client, put it on their playlist. But BA didn''t add it to its weekly recommended playlist. Two months later, the song died.

For BA''s client stations, an ironclad reasoning dictates these decisions.

"There is a formula, a real value system to what works," explains Dore Steinberg, music director at KKSF until three years ago. "If you go off on a synth guitar solo that rocks out or your saxophone bleeps or you puncture that atmosphere for a moment, you either have to find an edit to get that out or it''s not going to get play. It''s that serious. It''s that disciplined."

What these artists pine for is the good old days. Dubbed "The Wave," the format was Cody''s brainchild, begun in 1987 at KTWV in Los Angeles. Cody wanted to play music popular with Baby Boomers that couldn''t seem to find a home elsewhere. With New Age underpinnings, The Wave boldly mixed Sting and Steely Dan, John Coltrane and Chick Corea, Yanni and Enya, Andy Narell and Mark Isham, Boz Scaggs and Joni Mitchell, Sarah Vaughan and Sade.

Other radio stations followed. By 1990, however, Arbitron ratings tumbled for many of them. Some stations dropped below a 2 share (meaning less than 2 percent of a city''s radio listeners tuned in every quarter hour). BA, founded by Cody in 1988, moved in and aggressively marketed its research-based testing to flagging stations with stellar results. Ratings for client stations shot up from 2 to nearly 6. Today, most Smooth Jazz stations sit among the top 5 in their markets for radio''s most coveted demographic, ages 25-54, a group with lots of disposable income.

Analysts cite several reasons for the format''s meteoric success, including its multi-racial appeal, gender-balanced listenership and lack of direct competition. Weeding out music that didn''t test well also drove up Arbitron numbers.

"We were playing a lot of music that was unimportant to the masses," says Allen Kepler, BA''s vice president of programming. "We had a small group of people that were happy with the station, but the stations weren''t functioning as successful businesses, and they weren''t getting the ratings that you need to compete."

Also, BA successfully promoted a sea-change in radio programming. Instead of playing up to three cuts from one album, the industry moved to playing one cut per album. Playlists shrank. Now, there are less slots for new songs and more competition for airplay. But stations now ensure more spins each week for the artist. "It''s the only way the listener can learn the song and learn to like it," Kepler says.

Meanwhile, as airplay died, musicians and their management say domestic record sales for these artists dropped. "(Metheny''s) sales are actually down in the United States because of a major airplay problem, trying to get the music heard," says David Shollemson, Metheny''s manager with Ted Kurland Associates in Boston.

Consultants saved the format from going the way of eight-track tapes, but "this Smooth Jazz no longer offers the depth and diversity it once did," concedes Carol Archer, Smooth Jazz editor for Radio & Records. "So the listener and, sadly, the artist, too, has to give something up to get something."

When asked to defend "research" and its impacts, program directors do so on economic terms. "The decisions we make are a balance between art and science," says Paul Goldstein, vice president of programming at KKSF. "The way we keep our jobs in the programming department is we deliver ratings that our sales department can sell. When you''re paying $100 million for a radio station, being in 10th place won''t sell."

According to Cody, BA''s sacred, weekly playlist is the sum total of in-house research, feedback from client program directors and, only then, lots of testing. Other stations imitate BA with Pavlovian responses because client stations top the ratings, Cody says. "As consultants, we''re partners, coaches and collaborators, and certainly not didactic in our approach."

But is playing 10 seconds of music for a carefully, pre-screened group of people the way to get out of 10th place?

"Absolutely," says Kepler. Most people make up their mind about a song within two to three seconds, especially familiar ones, he says. "Think of any song you heard growing up as a kid and what part do you think of? You think of that 10- to 12-second hook that recurred over and over in a song."

Classical music? Fifteen seconds, tops, for a test group to say whether Bach, Beethoven or Brahms has the right stuff, says Kepler, a former French horn student at University of Kansas, who left after two years to pursue a radio career. As a student, "my observation was, the more you studied it, the more you got into real jazz or real classical, the further away you got from palatable music. You got into more dissonant sounding, complex music, that quite frankly, for a normal listener is difficult to listen to."

Yet, those flunking the tests never compose by the rigid formula of Smooth Jazz, a music that resembles vocal pop music--without the vocals. They''re more likely to draw their inspiration from bop masters; Latin, Brazilian and African music; or modern classical composers like Igor Stravinsky, Aaron Copland or Samuel Barber.

Metheny is known for symphony-like opuses that combine rhythmically complex meters with colorful harmonic textures. "To really develop our ideas, we don''t think, ''We''ve only got three minutes to do that,''" Metheny offers. "We let the music decide."

Kepler, Cody and others say they like creative music; it just doesn''t test well and won''t sell ads. "(However), if you''re a musician and you put together a great 3 1/2 to to 4-minute tune, it''s going to sound awesome on the radio," Kepler says, matter of factly. "That''s going to sell your record. And that''s what the radio stations need from Pat Metheny and the Yellowjackets."

"It''s not a joke," Metheny bristles. "It''s not about getting people to tap their foot or that kind of stuff. If I was going to do that, I''d be writing jingles for McDonalds."

Musicians like Metheny aren''t alone in criticizing the tests.

"With good music, a full listening to the entire piece doesn''t give you enough information about form, content and style to really understand that piece and so to imagine that someone could do it in 10 seconds is beyond reason," says composer David Cope, professor of music at University of California, Santa Cruz.

"On the other hand, most people don''t want to listen," Cope continues. "They want something to sort of underlie their existence with some kind of acoustic, and as a result, that''s why most people play radios in their cars and while they''re cooking."

So then, where do these artists, now winnowed off the airwaves, go for airplay? Kepler suggests "specialty" shows, such as Ramsey Lewis'' "The Legends of Jazz," syndicated by Chancellor, which airs on KKSF on Sunday nights. Pre-recorded in Chicago, Lewis offers snippets of Ella Fitzgerald and Duke Ellington buried amidst stacks of Grover Washington, Richard Elliot and Dave Koz. And specialty shows play it safe when delving into swinging, mainstream fare, carefully relying on melodious content that won''t offend.

Then there''s public radio, Kepler suggests, the final resting place of mainstream jazz since KJAZ in Alameda, the country''s last commercial all-jazz station, went off the air in 1994. But even nonprofits, reeling from funding crises, feel the pinch: Some of those stations are now turning to testing.

"We''re in a very funny spot," says Metheny, "because all of the so-called jazz stations have gone completely to a format that''s just as restrictive. They either play only avant garde or mainstream or a little of both."

"It seems like that in the course of history, the people that have had the biggest impact are the people that rock the boat," the Yellowjackets'' Russell Ferrante laments. "They''re not the people who deliver the easy things. They''re people that challenged the ideas that were expected at the time. They''re people who saw things from a really different angle. And I don''t think we move forward (as a society) unless we have that." cw