IF YOU'VE BEEN TOLD that good music and good business are mutually exclusive pursuits, particularly on a local level, consider stopping by the Saloon in Georgetown some night for a between-sets second opinion from Larry Seals.

Make it a brief discussion, though. Because when Seals and his Washington-based jazz-fusion quartet tell a club owner that they'll take 15-minute breaks, they generally take 15 minutes. Not 20 minutes. Usually not even 16.

"Music is music, but it's a business, too," says Seals, uttering softly what surely will be the next big musicians' cliche by 1990 -- but what for now, in downtown 1984 Washington D.C., is kind of a heartening thing to hear.

"I was lucky to have the chance to play in some very well- managed bands," says Seals, speaking of the 10 years he spent in progressive jazz, soul and top-40 bands (mostly in his native South Carolina) before coming to Howard University in 1982 to pursue a post-grad music degree. "And I was able to learn a lot from that."

Not that Seals didn't pick up a little from the studies, too (he's eight credit hours from a master's in classical saxophone performance). Or that the other three-fourths of what is frankly an extremely tight, accomplished ensemble -- drummer Richard Seals (Larry's brother; B.A. music, North Carolina Central), keyboard player Michael Bearden and bassist Michael Bowie (both music-education majors at Howard) -- didn't do likewise.

It's just that what impresses you -- if you dig beyond the music, about half of which is original, and let's say two-thirds satisfying -- is the thought Seals and the others put into the structure of both the band and its performances before anybody got anywhere near a stage.

"Most jazz bands don't rehearse to perfect the band, because the individuals are so good," says Seals, who has been through about a dozen bassists and half as many keyboardists and drummers since starting the band -- make that "concept" -- 21/2 years ago. "But I wanted a really good ensemble sound -- a unit. And after going through so many players who wanted to show themselves off and maybe have the band compromise and go with them, I just said, 'You fit in. We'll give you some leeway, and you fit into LSQ.'

This kind of talk may not win Seals any close friends in some mainstream jazz circles (and LSQ started out with a standard Coltrane-Rollins-Tatum repertoire before adding the likes of Grover Washington Jr., Weather Report and Billy Cobham). But then, some mainstream jazz artists will stretch a 16-bar improvisation to 27 minutes -- which is fine if you're high, or don't have to work tomorrow, or both. But which doesn't sound much like D.C. to me.

LSQ's shows are dense, digestible and it sure is hard to find a seat at the Saloon tonight. It is easy to find a band schedule, though; they're on every table.

Seals says the move to Washington, and to Howard, was deliberate. "I wanted a city that was closer to New York (than the Carolinas), where a young artist could practice his art -- and Washington is an excellent area for young musicians. In New York, you have a lot more professionals who will work for a lot less than they would elsewhere, because there's so many of them. And an unknown has a really hard time because he has to compete with professionals."

In any case, LSQ does weddings, the Hyatt in tuxedos if it has to, colleges (even George Mason U., right there in the middle of Led Zeppelin land), and nowadays regularly plays the Saloon, the Wharf in Alexandria and Isola Verde in Adams Morgan. And Seals won't give out ages (they're all in their early-to mid-20s; he says their youthful appearance -- particularly Bearden's and Bowie's -- has cost them work).

All is not dollar signs and daisies, of course. LSQ would like very much to record, Seals says, but at the momnt the band is having (and this would be funny if it wasn't serious) some business-related problems -- centering on a management agreement LSQ signed and is hoping to extricate itself from.

"We felt it was necessary at the time," Seals says, "and it just didn't work . . . You just learn through experience. That's the most dangerous part of music -- you can work for 12 years, then make the wrong move in management and all of it goes up in smoke." LSQ -- Appearing this Friday-Saturday (and January 16, 23, 25-26, 30) at The Saloon, 3239 M St. NW; January 18 at the Wharf, 119 King St., Alexandria; January 19 at Night Gallery, 1100 Blair Mill Road, Silver Spring; and every Thursday this month at Isola Verde Restaurant, 2327 18th St. NW.