Photo: Four on the Floor-Larry Carlton, Bob James, Nathan East and Harvey Mason will play the final show of this summer''s Concerts by the Bay series.

The members of the smooth jazz supergroup Fourplay must have known they were setting themselves up for some ribbing when they chose their name. In truth, the quartet does deal more in tantalizing build ups than explosive climaxes, but these guys have experienced hands and know exactly how to keep their fans satisfied.

Founded in 1991 by guitarist Lee Ritenour, pianist/keyboardist Bob James, bassist Nathan East and drummer Harvey Mason, the group has practically defined classy smooth jazz for the past decade. With Larry Carlton taking over the guitar chair in 1998, Fourplay''s sound gained an appealing edge, but hasn''t strayed far from the tried-and-true formula of polite R&B and instrumental pop with a jazzy sensibility.

Another major change took place when, after a decade with Warner Bros., the band signed with RCA/Victor. The recent release of Fourplay''s debut for the label, Heartfelt, indicates that the group hasn''t lost its focus. From the funk of Galaxia to the rock-tinged Karma and the bluesy Ju-Ju, the album delivers the tasty, well-crafted tunes that have won the band such a large following.

It''s not surprising that these guys know how to write crowd-pleasing material, as all four players have extensive credits as studio musicians.

There was practically a law in the 1970s that no tune was allowed on the charts unless Carlton played on it. His credits include Steely Dan, Joni Mitchell, Michael Jackson, Quincy Jones, Bobby "Blue" Bland, Dolly Parton, Linda Ronstadt, Herb Alpert and literally hundreds of other sessions. A close call with death after being shot by outside his LA studio in the late ''80s slowed Carlton down, but after extensive physical therapy he regained his voice and his chops and still possesses one of the most beautiful, searing guitar sounds in the business. His album No Substitutions-Live In Osaka with Steve Lukather is up for a Grammy for Best Pop Instrumental Album.

James started his career as an advanced bebopper. He spent much of the mid-''60s accompanying the glorious jazz vocalist Sarah Vaughan, and then devoted himself to studio work, producing a number of popular albums for CTI. By the mid-''70s he was one of the artists pioneering the smooth jazz sound through his own albums and collaborations with players like guitarist Earl Klugh and alto saxophonist David Sanborn. While he has continued to release his own recordings-his new CD Morning Noon and Night is due out next month-he has put much of his energy in recent years into Fourplay. The band seems to satisfy his desire to make commercial music that still allows some space for improvisation. Pianist/composer Jim Chappell, who has been a leading figure in new age music for more than a decade, opens the show.

Saturday, August 24. Grand Regency Ballroom, Hyatt Regency Monterey, 1 Goilf Course Road. 8pm. Tickets are $50 and $75. 649-1223.