Thousands roared back "yes!" as Tomorrowland, one of the world's biggest dance music festivals, made its China debut this weekend.

The move is a vote of confidence in the country's small but lively electronic dance music (EDM) scene -- and in its earning potential, despite slack consumer demand elsewhere in the economy.

Renowned for its star-studded line-ups and spectacular stagecraft, Tomorrowland's home edition in Belgium's Boom is a bucket list item for many hardcore ravers.

"For me, Tomorrowland is a dream," said Chinese EDM fan Mark, wearing sunglasses and a bright yellow arrow headdress.

EDM was "relatively niche" in China, he said, but that could change.

"Over the course of the last 10 years it's really flourished, and now I feel like everyone around me -- including my parents -- have all started to learn about EDM," he said.

Tomorrowland is betting on enthusiasm growing among a young urban middle class looking to "premium-ise" their partying, said Cameron Sunkel of specialist outlet EDM.com.

"China, in my eyes, is where the demand curve is steepest for this type of experience," he said, comparing it to mature European and American markets where "production costs are climbing" for only incremental growth.

A spokeswoman for Tomorrowland told AFP they believed "strongly in China's long-term opportunities".

She compared it to Brazil, where Tomorrowland has hosted festivals since 2015.

"(It) was also a niche market when we first arrived, yet today we see a fast-growing community and incredible local talent emerging," she said.

- Feel-good economy -

"The Magic of Tomorrowland" is the festival's first event indoors.

On Saturday, many entering the main building gasped at the sight of the castle-like stage dominating one side of the cavernous hall, set against a 374-square-metre (4,000-square-foot) video wall.

At the second smaller stage, dancers shrieked as confetti cannons fired simultaneously with a bass drop, glitter falling like shimmering rain.

Slow domestic demand is vexing Chinese authorities, but young people in particular appear willing to splurge on "emotional consumption" -- things that make them feel good.

In 2024, ticket revenues from large- and medium-sized concerts and festivals grew by 66.5 percent to almost $4.2 billion, an annual industry report showed.

Tomorrowland is not alone in eyeing up the potential -- major festivals including Ultra and Creamfields have also held China editions.

Momentum was lost during the pandemic though.

"Ten years ago in Shanghai, there were a lot of EDM bars, but actually nowadays there's not that many," Grace, a 29-year-old Chinese influencer in hot-pink flares told AFP.

"So for a big (brand) like this to come to China, I'm obviously very excited."

- Tightly managed -

The 10,000-capacity Shanghai event is tiny compared to the Belgian one, which saw 400,000 people over two weekends this year.

In China, Tomorrowland has partnered with entertainment companies Hero Esports and INS Land, and was supported by local authorities keen to burnish the city's international hub credentials.

The purpose-built main stage building was completed in just five months, including over a thousand moving lights, 118 speakers and dozens of laser, smoke and bubble machines.

The aim is to present "a fairy tale, an entire experience", said the event marketing chief, Hero Esports' Jay Lu.

EDM.com's Sunkel said the indoor event was "a way for Tomorrowland to test how their universe lands in China, how it's received under tightly managed conditions".

Common at such events in China, there was a visible security presence, and the last act -- global star Dimitri Vegas joined by Chinese rapper Masiwei -- finished at 10pm.

Some Europeans said they were bemused to find the bar payment system only allowed each person two alcoholic drinks for the event.

None of the organisers would divulge the costs involved in the event, nor exactly how long the partnership was set to last.

"We're excited for a long-term partnership so that we can educate the Chinese community on what EDM is... (and) just increase the bar for this whole industry," the event's CEO, Hero Esports' Clinton Lau, told AFP.

Asked whether this year would make a profit, Lau smiled.

"Every time you build something so grand... it takes time for the market to mature," he said.

"So we're starting here."