BASSIST CHRISTIAN McBride is a master of both the acoustic and the electric, and if you meld those two words hard enough, you kinda come up with . . . eclectic! The word's dictionary definition is "selecting from various systems, doctrines, sources," and that's exactly what the acclaimed young bassist has been doing for the majority of his 31 years, a process he continues to refine on the new Christian McBride Band album, "Vertical Vision." It's a bracing brew of acoustic and electric instrumentation, straight-ahead and fusion jazz, irresistible swing and irrepressible funk.

For McBride, it's all about range and possibilities.

"I've always strived for that diversity factor," McBride explains. "Unfortunately, we're in a time now where that's not really a good thing for radio stations and record companies. They like the music to be in a really predictable box so they can market it more easily."

McBride has never made that easy.

After all, he first came to prominence at the end of the '80s playing straight-ahead jazz on acoustic upright bass. That was the era when a pack of Young Lions -- Wynton Marsalis, Joshua Redman, Roy Hargrove, Nicholas Payton, Terence Blanchard, Cyrus Chestnut, James Carter and others -- helped revive the public profile, and financial health, of the jazz genre from a foundation of classic bebop and hard-bop styles. Like his peers, McBride was anointed a torchbearer for traditionalism. In 1992, Rolling Stone named him "Hot Jazz Artist of the Year." He was 20 years old.

Unlike his peers, who rushed out albums, McBride bided his time, acquired experience and found himself blessed to be mentored by many masters, including Ray Brown, who invited the youngster to join him and John Clayton in SuperBass. On "Gettin' to It," his 1994 debut as a leader, McBride recorded "Splanky" with Brown and the equally venerable Milt Hinton, resulting in a three-bass hit that was testimony to timeless invention.

But it wasn't long before McBride started testing die-hard jazz traditionalists. First up was 1998's "A Family Affair," which combined straight-ahead jazz and jazz versions of old-school funk and R&B tunes and featured McBride's electric bass on half the tracks. Two years later came "Sci-Fi," featuring further electronics and jazz interpretations of rock standards such as Steely Dan's "Aja" and the Police's "Walking on the Moon."

Which is why McBride sees "Vertical Vision" as linear development -- not radical revisionism -- and his most focused band project yet.

"For those who've kept track of the previous band CDs I've done, hopefully they'll be able to hear that this is the most special band I've ever had," he says. "This is the first band I've had where everybody in the band likes to do everything just as much as I do, and is as comfortable getting involved with different styles as I am. No idea is too weird for these guys. They're just as crazy as I am and I love that!"

Those weird and crazy guys include saxophonist Ron Blake, drummer Terreon Gully, guitarist David Gilmore, percussionist Daniel Sadownick and Geoff Keezer, a wiz on acoustic piano, Rhodes electric and Moog synthesizer and for many years McBride's ablest foil. With this lineup, the Christian McBride Band is likely to earn comparisons to such fusion pioneers as Weather Report, Return to Forever and Bitches Brew-era Miles Davis as well as various British prog-rockers: McBride has described the album's expansive jazz-rock opener, "Technicolor Nightmare," as "Miles meets Yes."

According to McBride, the album "wasn't really built around a musical concept, but more around the energy of the band." And its versatility, of course. For instance, McBride is as comfortable treating his upright bass with distortion, delay and wah-wah effects as he is "walking" it in the more traditional manner, and he switches up effortlessly between acoustic and electric both in the studio and onstage.

If you want to identify the roots of McBride's eclecticism, look no further than his hometown of Philadelphia, home of the fabled Philadelphia Orchestra, beloved Philadelphia International Records and numerous jazz luminaries. "The culture of that city is so potent, with the classical legacy, the jazz legacy, the R&B legacy," McBride points out. "It has a little of everything and each style of music is really deep in that city."

The bass legacy is more familial: McBride's father played with such Philadelphia soul stalwarts as the Delfonics and Billy Paul, while his great-uncle played with jazz vanguardists Sun Ra and Khan Jamal. The precocious McBride picked up electric bass at age 9, switched to acoustic at 11 and at 13 began sitting in with local bands of many stripes. Marsalis first noticed McBride as a young cub; the trumpeter was giving a jazz workshop at the Philadelphia High School for the Creative and Performing Arts when he was impressed by the 14-year-old freshman. It was at CAPA orchestra rehearsals that McBride first met percussionist Ahmir Thompson, who would soon connect with fellow student Tariq Trotter. Unable to afford equipment, they would re-create classic hip-hop tracks with Thompson's drum kit backing Trotter's rhymes. Now better known as ?uestlove and Black Thought, they are the heart and soul of the Roots.

Looking back, the 1989 school talent show must have been something special. Besides McBride, Thompson and Trotter, the Class of '89 included organist Joey DeFrancesco, guitarist Kurt Rosenwinkle and singers Amel Larrieux (Groove Theory) and Marc Nelson, plus all four members of Boyz II Men!

"Each day goes by and I remember how incredible it was, not only that so many talented people went to the same school, but that we all graduated the same year," McBride says. "It was a good year."

There was a mini-reunion a couple of years ago when McBride and Thompson worked on "The Philadelphia Experiment," a jam-oriented, city-centric celebration featuring such native sons as McBride, Thompson, guitarist Pat Martino, cellist Larry Gold and pianist Uri Caine.

That album ends with a hidden track, a two-tracked acoustic-electric bass rendition of Bill Withers's "Just the Two of Us," which is appropriate: Duality had always been an issue for McBride. After graduating from CAPA, the 17-year old received a scholarship to New York's Juilliard School of Music, and his original concept was to pursue concurrent classical and jazz careers. A few weeks into his first semester, McBride joined Bobby Watson's Horizon, and though he completed only one full year, he would continue his schooling in New York clubs and studios and on the road, including a three-year stint with Freddie Hubbard. By the mid-'90s, he had matriculated as the most acclaimed acoustic and electric bassist of his generation.

McBride now finds himself in need of a "Multiplicity"-style miracle. Even as he pursues his own recording and concert career, he's as much in demand for recording sessions as Ray Brown, his mentor, was in the five decades before his death last year. Besides directing three different jazz programs around the country and teaching numerous workshops, McBride also fills the bass slot for Sting when that occasional bassist tours (check out their acoustic-electric pulse on "Every Breath You Take" from Sting's "All This Time" live album).

McBride even found time to put together a big band -- for one night only.

"Geoff and Terry were unavailable for a gig and I didn't want to hire substitutes and still go under the moniker 'Christian McBride Band,' " McBride explains. "So I got really ambitious and decided to hire 13 other guys and get a big band! I'd been writing a lot for big band on the side but never had an outlet in which to perform it. So I put together this little big band, we had a great time and hopefully in the future I'll get to do some more big-band concerts."

Oddly, the big band's sound is relatively traditional, McBride says. "That's part of the mix-up that I like: go out there with my own band and come right back to [traditional] ground with the big band or on a gig with Benny Green and Russell Malone. Or do a gig with Sting, go all the way with something else like the Philadelphia Experiment, or do a gig with Carly Simon and go somewhere else.

"I really like being all over the place."

CHRISTIAN MCBRIDE BAND -- Appearing Wednesday through April 4 at Blues Alley. * To hear a free Sound Bite from the Christian McBride Band, call Post-Haste at 202-334-9000 and press 8101. (Prince William residents, call 703-690-4110.)

Christian McBride displays the diversity of jazz on "Vertical Vision."