More than 14.7 million millennials (18-to-34-year-olds) attend at least one music festival ever year. And with $1.34 billion spent on live music and festival sponsorships in 2014 alone, they’re more receptive than ever to marketing -- albeit done the right way.

A new study conducted by music marketing agency Momentum Worldwide and concert promoter AEG Live surveying 1,048 adults (75 percent of whom were millennials) found that 93 percent of 18- to 34-year-olds like brands who sponsor live music events, with eight in 10 citing branded festivals and concerts as the best way to engage with them.

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But making them memorable is still a challenge. “Millennials aren’t always retaining which brands they interact with at live music -- that’s a real gut check for us,” says Glenn Minerley, VP-group director of music and entertainment at Momentum Worldwide. “The industry’s just not doing music-marketing experiences right -- it’s not about putting a car on a pedestal in a festival village anymore.”

Still, Momentum and AEG’s research found that millennials who’ve attended at least one live music event in the past year are also more likely to trust brand partners (83 percent, vs. 53 percent non-attendees), purchase their products (80 percent purchase intent vs. 55 percent non-attendees), make social-media recommendations (80 percent vs. 49 percent), and perceive them as authentic (89 percent vs. 56 percent).

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Social media is crucial too. “Not just in terms of capturing those FOMO and #YOLO moments, but 70 percent of respondents told us it actually improves the live event experience,” says Scott Carlis, vice president-digital, social media and marketing at AEG Live. “That makes it critically important for us on the corporate and business side to make sure we have the opportunity to create social-media channels that work and function optimally, and share that intelligence with our clients to make sure they have the right mobile-first creative programming in place.”

Other unique findings? Owning music is still important -- 77 percent of millennial respondents say they prefer to purchase music vs. streaming it, while 78 percent said they typically buy music after a live experience (while 73 percent said they would stream). Exclusive content is important too -- 37 percent of millennials said they’re more likely to purchase the product of a brand that provides exclusive content, while 58 percent said they were more likely to recommend the brand.

Momentum's key brand clients include Verizon Wireless and American Express, the latter of which became the first credit-card sponsor of AEG/Goldenvoice's Coachella in April. Another study detailing millennials and music, released earlier this year by WPP's Group M, found that frequent concertgoers were more likely to a premium for recorded music they heard at a live event.