One of the most influential, and underreported, trends of San Francisco nightlife in the past few years has been the feisty reinvigoration of the jazz scene. Yoshi's Fillmore , which opened in 2007, finally seemed to settle into its giant digs in that historic district — and, despite fears to the contrary, didn't crowd out the stellar, more established jazz joints around it like Rasselas  and Sheba Lounge . It also helped expand the traditional jazz palate into famously funkier territory — this month at Yoshi's boasts the Ohio Players, The Family Stone, War, George Clinton and Parliament Funkadelic, and Public Enemy with a live band. (What, no full orchestra? Flava Flav needs some glockenspiel.)
Also recently, San Francisco sent its huge and hip Jazz Mafia collective around the country performing uptempo "hip-hop symphony" Brass, Bows, and Beats. Unfortunately the Mafia's homebase, Coda, closed on the first of this year — along with another beloved club, Triple Crown — citing the economic climate, but the supper club valiantly kept true to its live jazz mission to the end and shimmied with packed aficionados. Club Verde's spunky Tuesday Night Jump! (Tuesdays, 9 p.m., $12. 2424 Mariposa, SF. www.oldtimey.net/tuesdays ) with live band Stompy Jones revived that classic SF rockabilly swing vibe. Meanwhile, over at Martuni's piano bar (4 Valencia, SF. 415-241-0205) near the Castro, a new generation seemed to discover its inner Sondheim, tipsily belting a few out 'round the gleaming ebonies and ivories. Send in those damn clowns already, Jesus.
That jazzy hometown spirit of expanding definitions and embracing the musical past as a living thing, not just some retro curiosity frozen into easily marketed poses, has graced other scenes as well. Even as you're funking hard on the floor to some old school disco cuts or electronic productions, it's hard not to hear echoes of jazz's open-minded complexity working somewhere in the background.
And one of the parties I've funked hardest at lately has been Loose Joints  (Fridays, 10 p.m., $5. MakeOut Room, 3225 22nd St., SF. www.makeoutroom.com ). Let me be clear: Loose Joints isn't a jazz club — although on a recent visit, DJ Tom Thump expertly melted London all-horn ensemble Brassroots' 2010 New Orleans-leaning version of Inner City's 1988 Detroit techno classic "Good Life" into Bill Withers' Hammond-driven soul stomper "Harlem" from 1971. (At that point along my night's journey, I needed a new pair of hotpants.) It's more of an improvisational, all-vinyl DJ jam session that uses classic funk as its departure point. Hitting a tuneful sweet spot neither too familiar nor too abstract, Loose Joints has one of the best brain-to-feet ratios in the city: music nerds will dance their tight glasses off, straight-up partiers will discover where all those groovy samples come from.
The core trio of DJs at the heart of Loose Joints is a wild combination, rotating rapidly behind the tables. Founder Tom Thump digs deep into the wide-ranging, rarity-seeking global funk scene that brings to mind great DJs like Greg Wilson and Gilles Peterson (especially Peterson's Brownswood Recordings project). Damon Bell reps Oakland's fantastic, proudly abstract Deepblak techno scene, with a soulful Afro-Cuban twist. (Don't sleep on his "multiple mind-space" Kush Musik series on Deepblak Recordings, www.deepblakmusic.com .) And DJ Centipede, who helps put on the headiest club going right now, Change the Beat  (Tuesdays, 9 p.m., free. SOM, 2925 16th St., SF. www.som-bar.com ), brings a future bass and experimental low-end background to the proceedings. Somehow they average out into a completely accessible and danceable entity.
"We are a strange triumvirate," Thump told me. "I planned that, it was by design. I've known Centipede for years, when he used come into [Haight Street record store] Groove Merchant. So talented and unique. And I saw Damon play at [now-closed Panhandle club] Poleng one night a few years ago and was blown away by his soulful tunes. We are just one of my serendipitous flights of fancy."
"Loose Joints" itself is a sly wink toward the experimental-made-accessible, a name cribbed by Damon from left-field dance music hero Arthur Russell's popular side project, which put out the 1980 hit "Is It All Over My Face." It also refers to the loose style the trio applies to mixing their vinyl cuts. (They leave other, more elevating interpretations to the imagination.)
The party is put on well from a practical standpoint, although the MakeOut Room's layout is a bit strangulating near the door and it could use another person or two behind the bar. Because the MakeOut hosts live acts earlier in the evening, you'll encounter a thrilling grab-bag of leftover patrons. The crowd is comfortable and open, dancing itself into frenzy. (When I dropped by last month, there was a gaggle of super-hot boys and girls grappling each other woozily to the floor, which was just fine. But watch where you step.) The strip of 22nd Street between Shotwell and Valencia has really taken on a European plaza air of late, with several bars and cafes spilling over with exuberant sophisticates. We need to ban cars there. And there's also a healthy dose of newbie tech types — including the one in front of me in line who couldn't believe the door guy wouldn't take Visa for the $5 cover.
"San Francisco is so fucking beautifully diverse, that's why the party goes so hard," Centipede told me. "All types of life dancing to the same bassline." Thump said: "There are a lot of people into funky sounds right now — from 1960s girl groups and Latin disco to post-punk and newer Afro-electro. We're here to give all those a push. A sexy push."
LOOSE JOINTS TOP TUNES
Mim Sulieman (with Maurice Fulton), "Mingi"
Suzy Q, "Can't Give You Love (Persnickety All Stars Edit)"
The Fatback Band, "Wicky Wacky"
Bohannon, "Me And The Gang"