When tasting coffee, roasters and baristas let out this obnoxious sound. It’s guttural, like a throat clearing before a war cry. But it’s just slurps. It coaxes out coffee’s finer notes – and in the final round of the NSW AeroPress Championships held last Thursday at Paramount Coffee Project, it was all you could hear as the three judges carefully made their decision. The sudden tension shift stood out in a night that prides on not taking itself too seriously.

“The AeroPress competition is the most informal coffee competition in the circuit,” says first-time entrant and finalist James Perry of Sample Coffee. “You have a few drinks and take the piss a bit. Though a few take it seriously.”

The championships began in 2008 between three baristas in Oslo, but in time, everyone wanted in on the joke: now in its ninth year, winners from across the world will meet this November in Seoul to compete for the world title.

“It’s a pretty ridiculous competition when you think about it,” says finalist Angus Lindsay of Single O.

AeroPress by design is dead simple: complicating the plastic plunger with a competition pokes fun of the pretentious air of specialty coffee. In a community known to obsess over numbers and precision, these championships are refreshingly unscientific.

The rules are simple – three people per round, eight minutes max, use the same coffee (here an Ethiopian Bulga roasted by Reuben Hills).

Judging isn’t a manner of scorecards or even discussion, either. Pulled from Sydney’s top cafes, the judges were Fleetwood Macchiato’s head barista Cass Hayes, Reuben Hills’ head roaster Nick Theodore and Sample Coffee owner Reuben Mardan. They taste blind, and, on the count of three, just point.

Though, as Thursday proved, that means each judge might point to a different coffee. There was a muddle of laughs and moans from crowds and contestants, though it soon fell silent again. Three tie-breaker judges from Paramount took over. The slurping intensified.

“I had two thoughts,” says Perry. “First, ‘oh my God, I could be going to Seoul’ – well, Melbourne for Nationals, but then maybe Seoul – and then ‘I bet I’ve done one tiny thing wrong and that’s what’ll make me lose’.”

Perry’s competition, Lindsay and Philip Pollen of Pablo & Rusty’s, left him reason for pause: Lindsay, according to Perry, is a certified “legend” in Sydney’s specialty coffee scene, while Pollen was the reigning NSW Champion. They were the last standing from 27 competitors and three rounds, a near three-hour affair that, as I overheard a few people say, really made you crave a coffee.

The room was kept lively with reggae beats, beers from Sydney Brewing Company and tacos pumping out from Paramount’s small kitchen. Most of Sydney’s coffee connoisseurs were in the room. Everyone knew everyone, and while each competitor had a hype team, there were no lines drawn in the sand.

Over at the coffee bar, it was a tight squeeze of coffee grinders, cords, brewing tools and beers, as competitors made last-minute recipe adjustments and threw sledges. The event was male-dominated, noticeable in a cafe run by mostly female staff by day.

A tournament board on butcher’s paper marked the night’s progress behind the brew bar: sitting on top were AeroPress’s turned trophies, spray-painted gold, silver and bronze. Each competitor was given the coffee a week before the event, resulting in ambitious recipes.

“You know of that scene in The Simpsons where Barry White gets rid of all the town’s snakes with his singing vibrations?” says Perry. “I wanted to do that, but with coffee, using vibration to shake the particles and gain extra flavour, though mostly for stage presence. But it kept falling off.”

Perry came third. Lindsay, the runner-up, and two-year reigning champion Pollen both chemically altered their water with bi-carb soda and minerals like magnesium, a growing trend.

“It’s cleaner, sweeter and creates a more vibrant acidity,” says Pollen. “With just tap water, you get less flavour clarity. It’s a little muddy.”

So, how can you brew The Ultimate AeroPress at home? Pollen didn’t share specifics since he’s still in the game for Nationals, but you probably won’t want to re-create it at home.

“Oh yeah, my recipe is completely impractical,” says Pollen.

There was a lot going on between Pollen’s sieved coffee, the two kettles at slightly different temperatures, and his strategy to brew a stronger coffee then dilute it down. Pollen tested the strength with a refractometer, a tool that shoots light through a coffee sample to give a dissolved/solid score.

General advice proves more useful. Pollen rates filtered water, while Perry recommends using two filter papers for a cleaner coffee and pushing down “really, really slowly” over about 30-45 seconds. Lindsay says your best friend is a set of scales: if you weigh the coffee and water, you can do it again every time. Oh, and slurp. Really, really slurp.