For more than two decades, the San Jose Jazz Fest carved out its niche, little by little, season after season. Then last year, everything blew up.

What happened was that San Jose Jazz, which organizes the festival each year, made its biggest push ever for a mainstream audience. With a roster dominated by iconic funk acts like George Clinton, Maceo Parker and Tower of Power, it was a risky move for a music festival that still had “jazz” in its name.

Some purists may have scoffed, but the lineup was a great success. Not only did it draw the biggest audience in the history of the festival, but it put the organizers up there with the most progressive in the country—part of a quickly spreading movement that stresses inclusion and accessibility over strict genre boundaries. It also secured the Jazz Fest a spot among the top half-dozen jazz festivals in the country.

The ironic thing is that last year’s programming was only a splashier, more audacious version of what the festival has been doing all along. It hasn’t been a strictly jazz festival for years (if it ever was), but in the past it didn’t get the credit for its intriguing programming. How many knew, for instance, that it had quietly become the biggest Latin music festival on the West Coast?

If the key to last year was accepting a new range of genres, this year’s is accepting a new generation. There are the big headliners, of course, like blues and gospel legend Mavis Staples, and organizers have even gone back to the funk well with the Ohio Players.

San Jose Jazz’s new executive director, Michael Miller, knows it’s the main stage acts that will bring the biggest crowds, but he thinks the real heart of the festival lies with the up-and-coming musicians on the other nine stages.

“What we’re most proud of is giving these emerging artists a chance to be heard,” says Miller. “You’re seeing young twenty-somethings coming up with this great new sound.”

Indeed, this year the festival has managed to snag several young musicians making jazz and stretching its boundaries, just as they seem poised to break out.

“In a year or two, you’ll be able to say, ‘I saw them first at the San Jose Jazz Fest,’” says Miller.

Here are four up-and-coming acts to watch:

Trombone Shorty
Hearing Trombone Shorty’s record Backatown last year was the jazz equivalent of stumbling upon A Tribe Called Quest’s new brand of hip-hop in the early ‘90s. Only 25 years old and with a Grammy nomination and a chart-topping jazz album already under his belt, he has the power to influence his genre as much as Tribe changed theirs. More informally going by Troy Andrews, the guy can absolutely crush a beat, delivering heavy funk one minute, and a shimmering chill groove the next.

“We never sat down and really thought about concepts and what we wanted our music to sound like,” says Andrews. “It’s just that, over the years, we allowed each one of the band members to bring their influences and taste in music into our music. Also, being from the city of New Orleans and being able to hear different bands and musicians, as students of music, anything we hear or are influenced by, it naturally comes out in what we’re trying to do.”

Andrews has been playing trombone since he was 6, and was still a teenager when Lenny Kravitz took him out on tour. Having grown up in the Treme neighborhood, he worked with the New Orleans Social Club on their post-Katrina benefit work. His NOLA roots were fully in evidence on Backatown, but they may be even more so on his new record, For True, coming out this fall.

Among his collaborators on the album are a New Orleans cast of characters that includes Ivan and Cyril Neville, bounce rapper 5th Ward Weebie, the Rebirth Brass Band and Galactic’s Ben Ellman.

“We’ve got a lot of New Orleans people on this new record—the music just called for it. The Rebirth Brass Band, these are all people that helped me to grow in my career and teach me different things. And 5th Ward Weebie, who’s one of the lead voices in the bounce community, we’re like brothers,” says Andrews.

A testament to Andrews’ versatile sound is the fact that he’ll perform entirely different sets on San Jose Jazz Fest’s main stage (Saturday at 2pm) and blues stage (Saturday at 9pm).

Alfredo Rodriguez
It took Quincy Jones three years to convince pianist Alfredo Rodriguez to leave his native Cuba. Jones had watched him perform at the Montreux Jazz Festival in 2006, and declared him one of the best he’d ever seen. But the Havana-born Rodriguez didn’t take the decision to leave his family lightly and kept the legendary producer waiting until 2009.

Blending a Thelonious Monk-type inventiveness with classical precision, the 25-year-old Rodriguez will release the first fruits of his collaboration with Quincy when his debut album is released this fall. He plays the San Jose Jazz Fest with his trio on the San Jose Rep stage (Sunday at 6pm).

Zoe Keating
Indie music fans may know Zoe Keating from her stint in the Marilyn Manson/Nine Inch Nails-linked cello group Rasputina, or her guest appearance on two songs from Amanda Palmer’s debut album. But she’s better known for her electronically boosted, heavily layered solo sound, a powerful and atmospheric sonic cocktail that combines her classical training with a modern, cinematic feel. Appropriately, she is providing the music for Christopher Salmon’s animated adaptation of Neil Gaiman’s The Price. She performs on the Jazz Beyond Stage (Friday at 8pm).

Blues Caravan
Girls With Guitars: Before Yugoslavian singer-songwriter Ana Popovic was winning awards in this country, she was touring as part of the Blues Caravan. Every year, Ruf Records’ Caravan tour features three young female blues guitarists, and this year Dani Wilde is returning (having had an opening slot on the tour in 2008), along with Samantha Fish and Cassie Taylor.

British singer and guitarist Wilde got her start at 17, and her soulful-beyond-her-years voice and electric finger-picked sound has fueled two solo albums so far. At age 22, Fish has just broken out of the blues scene in Kansas City, Mo., with her debut album, Runaway, and a love of Southern-fried blues-rock.

Multi-instrumentalist Cassie Taylor grew up performing with her bluesman father Otis Taylor and, now in her 20s, is pursuing her own career. The trio lay the triple-threat guitar on heavy, and last year recorded a Girls With Guitars album together in Berlin, featuring an eyebrow-raising take on the Rolling Stones’ “Bitch.”

The San Jose Jazz Fest will be held Friday-Sunday, Aug. 12-14, at the Plaza de Cesar Chavez (Main Stage) and nine other stages in downtown San Jose.

Headliners include Mavis Staples, Arturo Sandoval, Ohio Players, DMS featuring George Duke, Marcus Miller and David Sanborn, and more. Music begins 5pm Friday, 10am Sat-Sun; tickets are $15 (Friday) and $20 (single-day Saturday and Sunday, $35 (two-day pass) and $45 (three-day pass). There are also VIP packages available.

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