When Steve Hays was voted "Best DJ" in SF Weekly's 2011 readers poll, it caused a minor uproar among local entertainers. How could Hays, who performs as DJ Purple, beat out the city's deep house and vinyl-spinning trendsetters? DJ Purple, after all, isn't exactly a DJ. He's a karaoke DJ.

"There was chatter among the house music DJs that they were pissed," recalls Jamie Jams, a DJ known for events like Debaser and Last Nite. "But I've seen a lot of those fools at his karaoke nights, and they know he's amazing."

Karaoke DJs, or KJs, aren't typically known for musicianship, although plenty are enthusiastic music fans and singers themselves. They hit play on requests, collect tips, and maybe grab a drink at the bar while singers do the dirty work. But Purple, who celebrates 10 years of his "Dance Karaoke" shows with an anniversary event tonight at Slate bar, is easily the hardest working performer in the room at any of his events — and maybe, with a grueling, full-time performance schedule, in the Bay Area altogether.

Purple is a one-man backing band, pulling instruments like a harmonica, cowbell, or his signature saxophone out of thin air to play singers through typically awkward instrumental sections. He's also a sound man, mixing levels to make you sound better than they you do to yourself in the shower. And then, in a flash, he's an effects wizard, flipping on lights and lasers and blasting a dramatic fog geyser machine. Of course, Purple is also a DJ, constantly curating his book of upbeat songs — no depressing heartbreak ballads here — and playing requests according to flow and genre rather than in the order they're submitted.

"You can't front on Purple," says Jamie, who now admits to secretly campaigning for him to win the SF Weekly award.

Steve Hays was born in New Jersey and came to the Bay Area to attend Stanford before dropping out twice to pursue music. "The second time kind of stuck," he says. Hays started playing clarinet in third grade, then moved to saxophone, later learning guitar and piano. In the '80s, as was the fashion, he taught himself to program drum machines and synthesizers. "I'd played in bands for most of my life, but there was a period where it got harder and harder," says Hays. "Keeping a band together, it's hard." As DJing gained popularity, Hays adopted his moniker — college friends called him Purple Hays after the Hendrix song — and found better pay with regular DJ gigs. But eventually, he got bored. "There's no performance," Hays complains. "As a DJ you're just kinda there."

But as a karaoke DJ, with a rotating cast of singers, Purple endeavors to take the best aspects of both disciplines. "His mission in life is to fix everything that's wrong with karaoke," says Jamie. There's plenty to address. First, that pesky instrumental solo. "Most singers are like, what do I do now?" says Purple. "Over the years I've found so many ways to step in and keep the show going." In some cases, that means learning new instruments. Purple recently started playing recorder specifically for the solo on "Wild Thing" by the Troggs — "It just doesn't sound right on the saxophone."

At Purple's regular Thursday night show at Slate last week, which was well attended by an energetic young crowd, some dressed up for the occasion, I was particularly impressed by the the variety of new songs in his book. The list is ever-changing, though the rules are always the same: "Every song I put in the book needs to keep people on the dance floor and interested," says Hays. New numbers aren't just carefully vetted — Purple needs to learn them. That means, for example, he can break into the instrumental solo on the Chainsmokers "Closer" without missing a beat, as he did to the delight of the bros singing it last week. "Part of my job is to know what songs are out, and reviewing them, to ask if they're going to have enough energy," Purple says. "I'll try to listen to it and say, 'is there an instrumental solo, what instrument am I gonna play?'"

There are some songs Purple expects to hear every night he performs: "Don't Stop Believing," "Sweet Caroline," and "Mr. Brightside," to name a few. But others in the book are sometimes overlooked. "Every Time We Touch" by Cascada, for example, has a sax solo he loves performing, and as a big fan of The Who, he'd be "super happy" if someone would sing "Won't Get Fooled Again." He's also a fan of Muse, performing one of their songs in a surreal moment with the comedian Craig Robinson on the Sketchfest stage during Outside Lands last year.

"There's nothing in the world like a DJ Purple show," says Allan Hough, editor of the blog Mission Mission and a longtime Purple fan. The collective effect of Purple's talents make him the host of a party, one where people happen to ask for, and then perform, song requests as friends and strangers cheer, sing, and dance along.

Purple's crowds ebb and flow at his weekly shows, Tuesday in North Beach, Wednesday in Redwood City, and Thursday in the Mission, with private events in between. But he's achieved massive attendance at some events, like a collaboration series called "Singin' & Pingin" with Hough's Berlin-style ping-pong league. "One of the best moments of my life was the time at a Singin' & Pingin' at Z Space where there were about 700 people in attendance," Hough remembers. "It was the month "Get Lucky" came out, and DJ Purple invited literally everyone to come up for a singalong. I'd say 100 people swarmed the stage and it was awesome."

Dance Karaoke started more humbly, at a down-and-out dive bar called Jack's Club. Ask any early 2000s Missionite about it and they'll get a faraway look in their eye. "The deal with Jack's," Jamie explains, "is it was this struggling, working class, open up at 6 in the morning kinda bar, where everyone there just got outta jail or the hospital. It was there forever, but we were just starting to go in 2005." Deep in the Mission past Potrero, "It was just far enough away that almost no customers would go, and just dangerous enough that you weren't really sure if you should, either."

The bar's owners had hired younger punk types for staff, and desperate to attract customers, asked them to help fill the space anywhere they could. Jamie was one of the first to book illegal, non-permitted DJ nights at the the bar, and when a popular punk venue closed, Jack's started booking full-on shows. "It was a madhouse," he recalls, "the neighbors banging on the ceiling, the bass rippling through the walls."

After years of evading police in a cat-and-mouse game, SFPD made clear to Jack's owners that no punk shows would be allowed, and no DJ nights, either. But to keep patrons, the bar would say yes to almost anything else. One of those things was Purple. "Karaoke was this loophole to continue having events at the bar," Jamie explains. "That," he says, "is the birth of Purple."

"Jack's is where I landed and everything sort of started," Purple recalls. "10 years ago was my first night, and it became this sort of phenomenon. It's this tiny little place, but part of the magic of it was it always felt full." The first several years at Jack's are some that Purple recalls as his heyday. "It was the golden era. There were a lot of creative people in the area, and the rent wasn't so high. The amount of energy and enthusiasm people put into the nightlife and performances was great."

Purple wasn't a hit right away. "It started with skepticism," Jamie recalls. "He's a tall, skinny, nerdy guy with glasses. Everything about it was like "who is this guy?" But Purple worked hard — "He just played a million great shows and the whole thing built cause of his relentless grind." By 2008, says Jamie, the phenomenon was undeniable.

Hough recalls those Thursdays at Jack's: "Mission kids and DJ Purple fanatics from down the peninsula and beyond, drinking mini-pitchers of Busch and packing the place to the hilt. I feel like you don't see crowd surfing in dive bars in SF anymore... so sad."

With Jack's a memory as distant as crowd surfing in dive bars, Purple has now performed at Slate on Thursdays for about five years. "It's taken a while to build up [the crowd] at a bigger place like [Slate]," says Purple. "When I came to Slate, at the time, I was thinking like, this will be just like a bigger version of Jack's. That was really the transition. But there was a big exodus from San Francisco at the time, and it was hard to [draw a crowd]. For a while there it was kind of a let down. Where's the magic?"

Patty West, who owns Slate, says she's noticed "a steady group of regulars" by now. "We have specific birthday and bachelorette groups that come in, often dressed up — a veil, tiara, a cake maybe. They don't tell us, they just show up," she says, which is fine with her. To keep a following going in the events business, consistency is king, and West calls Purple "the ultimate professional." Not just DJ Purple, he's roadie Purple, too, carrying all his own equipment. Like a Muni driver in his DJ booth, he'll gladly answer a quick question, but he'd prefer not to chat, and I'm not sure anyone has ever seen him use the bathroom during a set.

While you think he might prefer a vacation, instead, Purple says he'd consider adding a night at the right venue. "On my mind lately is what's next?" he says. Without Hough, whose press coverage and organizing helped catapult Dance Karaoke's popularity, Purple is seeking collaborators and promotional help. According to West, he's also experimenting with new ways to gain a following. "Back in the day, at Jack's, people looked at fliers more — and now no one does. He's started to recognize how important social media is, and so he's getting that out there."

Asked if he misses the golden era, Hough demurs, saying he'd like to think we can all have multiple golden eras. "Can you recapture [Jack's]? I don't think so, exactly. But the epic sound system and proper nightclub vibes at Slate definitely suit DJ Purple's show. He looks like Calvin Harris or somebody up there in the big DJ booth." There are, for the record, seven Calvin Harris songs in DJ Purple's songbook, as well as several by The Who.