It was a Tuesday night at Amnesia on Valencia Street, sometime in the early 2000s, when Glenn Calub spotted his friend Paul hovering near the stage. Paul loved the band Toto but had never sung karaoke and, due to stage fright or a lack of liquid courage, was never going to sing karaoke. 

Then Calub handed him a cordless microphone — and Paul started singing Toto’s “Rosanna.”

“For a lot of people, they have that fear of singing in front of people, kind of like how some people have a fear of public speaking,” Calub said. “There’s some moments when there’s a breakthrough, where someone is, like, ‘Hey, I’ll try it.’ Or you just hand them a mic, catch them off guard, you break the ice, and then they become hooked.”

That transformation — from white-knuckled perma-bystander to devoted open-throated regular — is what drives karaoke veterans. But karaoke has rules, most of them unwritten. Listen up to what some of San Francisco’s expert KJs say can help you excel at the ultimate nocturnal musical activity. 

“Everyone loves music,” he said. “And karaoke has always been a good way to meet people without even trying. You just kind of have a reason to be.”

“The magic of karaoke isn’t about being the best singer,” said Tom Dougherty, co-owner of Silver Cloud in the Marina. “It’s about sharing the moment with the rest of the people in the bar.”

It’s not about being good enough to perform; it’s about your desire and commitment to the song.

“Nobody is there because they’re talented,” said Dana Morrigan, who hosts queer-centered shows in San Francisco and the East Bay. “Talent is not a precondition for karaoke. Karaoke is for anybody who wants to sing.”

What if someone is averaging it out onstage but giving everything they have? “That’s spectacular,” she said. “It’s the effort and gumption that you should be proud of.”

The corollary, as Morrigan said with precision: “Being a critic of a karaoke singer is about the stupidest thing you can do.”

Ask Morrigan what advice she’d give a first-timer, and the answer comes fast: “Sing what you love.”

Not what you think the crowd wants to hear, what you figure will get the best reaction, or the one your friends are yelling at you to do.

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“People come up to me all the time and ask, ‘What should I sing?’ And that is always what I say,” she said. “The connection that you send out is going to resonate.”

Calub agrees, with one important addendum: Make sure you know the song well. It doesn’t hurt to practice at home.

“If you pick a hard one — if it’s fast and you don’t know it very well — you get behind,” he said. “‘We Didn’t Start the Fire’ by Billy Joel. ‘One Week’ by Barenaked Ladies. If you don’t know those songs, you’re gonna have trouble.”

Microphone position is key to being heard in a crowded room with lots of chitchat and other background noise. 

The correct method is to hold the mic directly in front of your mouth and sing into it — not past it, and not beneath it. If you hear feedback, bring the mic closer.

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“Singing close to the mic,” Morrigan said, “is probably the single thing that would make my life easier. That is the most important technical thing.”

“Most people have been ruined by watching television,” she added, “where people are lip-syncing or singing to a pre-recorded version of their songs. They hold the mic down here, or straight up, because they want their face to be visible to the camera.”

Avoid tapping on the microphone. The KJs often mute it between performers.

“Kids and adults pick up the mic and start pounding on it: ‘Hey, this mic isn’t working,’” Calub said. “I turn the levels down sometimes, because I’m trying to avoid feedback. Before the song starts, I start adjusting.”

On a busy night at The Mint on Market Street in the Mint Hill neighborhood, the queue can creep to a dozen or more songs.

The Mint’s house rules are simple: one solo and one group song in the queue at a time. As Jason Pederson, the resident KJ, put it: “We want everyone to have a fair opportunity to get up and belt out a tune if they like.”

Calub has seen every form of line-gaming in his 25-plus years behind the console. The move he finds most galling: singers who put in their name, wait a bit, then add a second name — or a group name — to cut the rotation.

“I call them up, and it’s the same people again. ‘Hey — you just sang. You’re cheating,’” he said.

Nobody likes a microphone hog, so give the other singers a chance to shine and use your downtime to get a drink before you hit the stage again.

“If there are 12 people on the list and you’re No. 6, do the math,” Calub said.

Calub has a friend who loves grunge: Soundgarden, Nirvana, Pearl Jam. While on a motorcycle trip, in the suburbs of Vancouver, they found a room full of older Canadians, and his grunge buddy sang “Rooster” by Alice in Chains.

Nobody clapped.

Calub got up and sang an Anne Murray ballad. The room erupted.

“Everyone started couples dancing,” he said.

“Picking the right song is key,” he added. “But picking the right moment — that’s key too. You have to read the energy. Knowing your audience is part of the enjoyment of karaoke.”

Morrigan offers an important caveat: The room’s energy is a moving target.

“By the time you get to sing, the energy will have changed,” she said. “The energy of the night is really just the energy of the ongoing five-minute period. You can go too far in trying to predict it.” That said, she acknowledged, “there are crowd songs, and there are quiet-room songs. Truly.”

There are some songs that never fail to electrify a room.

Among the crowd-pleasers are “Don’t Stop Believin’” by Journey, “Sweet Caroline” by Neil Diamond, and “My Way” by Frank Sinatra. If Boomer hits aren’t your cup of tea, the canon has grown to include some millennial material, such as “Before He Cheats” by Carrie Underwood and “Mr. Brightside” by the Killers.

Calub has a theory for why these songs dominate: “The radio hammers these hits over and over, to where everyone becomes shaped by it. You have populations in every major city saying, I want to sing ‘Sweet Caroline.’ How does that happen?”

He often marvels at karaoke singers who go for obscure cuts and draw from eclectic, personal playlists made up of acts unknown to most people. “You meet people who have very deep [picks], and you’re like, I’ve never heard that song before. They’re digging beyond the programming level.”