IT'S A TUESDAY evening at Chris' Jazz Café, but it feels more like Saturday night. The room is packed, the mood is vibrant, and there are 15 musicians projecting a raucous, full-throttle sound. The sound is large but not bombastic, raw without being sloppy, and seems to send an electric charge through the room.

Standing in front, wedged between the band overspilling the small stage and the front row of tables, is Orrin Evans, dancing back and forth and shouting encouragement and instructions. Suddenly, he shoves pianist Neil Podgurski aside, unable to resist taking the bench during trombonist Frank Lacy's solo on Evans' tense, spare "Song for the Jena 6."

Leading his new Captain Black Big Band, which began its Tuesday-night residency at Chris' last month and plans to continue in that slot at least through January, Evans seems to be hosting a party almost as much as he is conducting a big band. Between numbers, he jokes with longtime friends who are guest performers with the ensemble and complains about his spilled Long Island Iced Tea until a waitress brings another. Clapping the tempos loudly and vigorously nodding his head, he drives the band by prodding them to meet his own enthusiasm, enforcing a strict control on the invigorating vibe.

"This is food for the soul," Evans said of the big band a week later, keeping a firmer grip on another Long Island at a Mount Airy bar. "We're bringing good times and good feelings."

Not that there isn't serious music being generated. To make up the Captain Black Big Band, named for his late father's tobacco brand, Evans has called on a combination of both young and experienced instrumentalists from the Philly jazz scene and friends and collaborators from his frequent sojourns to New York. In the three gigs that it's played so far, the band has featured notables like trombonist Lacy, trumpeters Jack Walrath and Duane Eubanks, bassist Derrick Hodge, and saxophonist Ralph Bowen.

"I've always looked at a big band as an opportunity to use the skills you learned in school," Evans said. "You have to read, you have to learn to be a part of a section, and in Philly you don't get that opportunity very often. I like to do this bridge thing where I bring some of the New York cats down here to play with some of the Philly cats who might not get a chance to play with these guys otherwise."

For the younger musicians he employs in the ensemble, Evans sees his role as not only providing a regular gig, but mentorship and a networking opportunity. "You might go to the University of the Arts or Temple," he said, "but Tuesday nights you're coming to school."

One of the young Philly musicians who appreciates that opportunity is Wade Dean, who is himself an educator - director of jazz studies at the University of Pennsylvania - but is also an up-and-coming saxophonist. "As a young cat, this is everything you dream about," Dean said. "You listen to these cats and now they're your colleagues.

"You don't get this type of stuff in school. It's that real education they tell you about, the mentorship, the apprenticeship."

Dean played in the Captain Black sax section for the ensemble's first two performances, but had the night off with Ralph Bowen as a guest musician on the last Tuesday in November. Still, he was there, to support Evans' nascent effort at scene-building and simply to take the music in as a spectator for a change. Evans encourages this level of commitment, something he himself practices as an 11-year member of the Mingus Big Band, the New York-based ensemble that performs the music of legendary bassist Charles Mingus. When not on the bandstand, Evans said, he can often be found in the audience, listening to pianist Dave Kikoski's take on the repertoire.

Evans' long tenure in the Mingus Big Band was one of the inspirations behind forming his own large ensemble, and encouraged him to counterintuitively limit the band's rehearsal.

"I've been in the Mingus Band 11 years and I've probably had two rehearsals," he explained. "It really helps your musicianship, with being quick on your toes, not so much for sight-reading but for living in the moment of the music."

The result tends toward what Todd Bashore approvingly terms "organized chaos." The saxophonist has contributed arrangements to the band's book, currently working, Evans revealed, on a "hip version of 'Silent Night' " for their Christmas season shows.

"There's a lot of freedom within a structure," Bashore said. "No tune is ever going to be the same way twice. Orrin is like a chef adding ingredients to a pot as he feels like it, tasting all the time and seeing what it needs and then throwing something else in. It's a lot of fun for a musician to play in something like that, because it's creative and you never know what's going to happen. It keeps you on your toes."

Just how spontaneous the band can be is evidenced by pianist Neil Podgurski's experience. He received a call from Evans on the day of the band's first show asking him to play that night. When he asked the bandleader to e-mail him some of the music to look over, Evans simply shrugged the request off, saying, "You'll be fine."

"It's challenging," Podgurski said. "But he seems to run a tight ship, which is what a big band calls for. Orrin's got the confidence and the charisma to pull that off. He's very outspoken and exudes control."

Trombonist Ernest Stuart, a Philly native who moved to New York last summer, finds Evans' famed outspokenness and strong personality imprinted on the big band's musical identity, even in such early days.

"It's very straightforward, at times aggressive, with some humor in it," Stuart said. "It's kind of dark sometimes, other times it's extremely happy and joyous. I think that's a direct reflection of Orrin."

The music that the Captain Black band plays at this point is largely culled from the books of Evans' past employers and collaborators, including Ralph Peterson, Bobby Watson, and bassist Eric Revis, also a member of Evans' collective group Tarbaby. He plans to keep the music "in-house," taking arrangements and material contributed by members of the band.

The repertoire, he said, is "evolving, but the concept of how to approach the music is already set. We approach music with an open mind and the freedom to go wherever we want to go. It can be hard, because some people are stuck on what the paper says. Let's move beyond the paper. I want to take the small group concept and apply it to a big band."

That concept excites Lacy, at 50 one of the band's elders, who plays alongside Evans in the Mingus Big Band and has spent a storied career traversing avant-garde and mainstream jazz. "This band plays music of our generation, and I think that's very important," Lacy said. "The challenge is in the unfamiliarity, but the unfamiliarity is what gives the band its edge."

The presence of Lacy and other New Yorkers reflects Evans' presence on that scene despite living in Philadelphia. Born in Trenton, N.J., and raised in North Philly, he briefly made the move to Brooklyn, N.Y., in his younger days, but family demands brought him back home in 1998. With his two sons growing older, Evans said, he'll "always have a foot in Philly," but is contemplating relocating once again.

"I'm like a spy," Evans joked about his travels between the two cities. "I'll go down the turnpike to Exit 14, come back and tell Philly what's working down there - and see if we can get it happening here."

One of the concepts he's importing is taken from the Jazz Gallery's piano duo series, in which Evans has participated with fellow keyboardists including George Colligan, Gerald Clayton, and The Bad Plus' Ethan Iverson. At the end of this month, he'll move his own piano into Chris' for a pair of his own duo shows, with Mulgrew Miller and fellow Philly native Uri Caine.

"I wouldn't even call them duo shows," Evans said. "I call them getting paid to take a lesson. I'm the type of guy who says, 'Come to my playground.' I don't play well in other people's playgrounds. Maybe that's the Trenton in me. But I'm gonna get chewed up on my home turf, bringing in somebody else to whip on me."

Captain Black Big Band, 8 p.m. Tuesdays, $12; Orrin Evans with Mulgrew Miller, 8 and 10 p.m. Dec. 18, $20; Orrin Evans with Uri Caine, 8 and 10 p.m. Dec. 19, $20-$22; Chris' Jazz Café, 1421 Sansom St., 215-568-3131, www.chrisjazzcafe.com.