9 things we learned about Dave Grohl at ACL Fest conversation with Brené Brown

Author, professor and acclaimed mental health specialist Brené Brown sat down Friday to chat with perennial rock star Dave Grohl of the Foo Fighters on the Austin City Limits Music Festival’s Bonus Tracks stage.

“This is … strange,” he said up there, presumably because he wasn’t holding a guitar.

They discussed Brown’s new research on music and its power to “bring us together.” She also told onlookers that she’s a huge Foo Fighters fan.

Her work looks at what happens “when people who disagree enjoy music. The power of emotion,” she said.

Then the two broke down hit songs: “Music that makes us sing no matter what happens,” as Brown put it. Grohl added technical context, geeking about why bands such as Journey, Rush and the Who are good. And John Denver. And Bill Withers. And Garth Brooks. And how he loves Gloria Gaynor’s “I Will Survive.”

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“The best breakup song of all time,” he said, adding that it is as inspiring to a lovelorn individual as “Imagine” is to a “pacifist.”

Grohl and the Foo Fighters are headlining both Saturday nights of ACL Fest. The band also will record an episode of "Austin City Limits" on Thursday.

Here are nine things the veteran genre titan told fans and did while in conversation with Brown at Zilker:

Led a 'We Are the Champions' singalong while breaking down his pick for rock’s best-ever singer.

Arms outstretched, Grohl and Brown led Queen karaoke. She said that singer Freddy Mercury was found to be the most likely vocalist to inspire singalongs in a hundred-pub study. Grohl wasn’t surprised.

“Greatest rock vocalist of all time,” Grohl said. “My personal opinion.”

He said that’s because Mercury’s vocals were “powerful” and “vulnerable.”

“That dude onstage? No better frontman because he had no trouble laying it all on the line,” Grohl added, praising the late singer’s “operatic” singing.

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Sidebarred about 'Country Road'

“Why is it I can smell my mother’s car?” Grohl asked Brown about the John Denver song’s nostalgic power.

That song was co-written by the Starland Vocal Band in Washington, Grohl added. He said his father, a journalist in D.C., would regularly hang out in their bar during his ’70s heyday.

“It does take me back to when I was young in Virginia,” he said.

“Nothing does it as powerfully as music,” Brown said. “Nothing brings us to smell, sight, sound or emotion like music.”

Praised AC/DC’s deceptively easy drumming

“It comes down to feel. … It’s not something that can be created,” Grohl said of AC/DC’s Phil Rudd.

“He is not a fancy drummer. … He just lays it down, four-on-the-floor. He’s in the engine room.”

Air-drummed fills from Rush’s 'Tom Sawyer'

“I don’t know what that song is about,” Grohl noted. “But I can air-drum it.”

More: Tennis legend Venus Williams spotted at ACL Fest watching country artist Breland

Rebelled against the notion of guilty pleasures

“If you like something, like something,” he said, disparaging when music was “shrouded in irony.” (The slacker ’90s, probably.)

“You should just like what you like and just reserve the right to not like Journey,” he said, apparently dissing Brown’s decision to play us “Don’t Stop Believing.”

And then he praised “Never Gonna Give You Up” and said it was OK to love one-hit wonder Rick Astley.

Told a story about how he trolled Christopher Walken into mispronouncing his band’s name on 'Saturday Night Live'

“He comes up to me before the host introduces us and asks, ‘The accent. Is it on ‘Foo’ or ‘Fighters’?”

Grohl said it was “Fighters” as a joke, and the rest is a classic viral SNL gaffe: “Ladies and gentlemen, Foo FIGHTERS.”

Revealed how they got Rick Astley to sing 'Never Gonna Give You Up' with the band

Grohl said he and Taylor Hawkins covered "Never Gonna Give You Up" because it had the same "arrangement" as Nirvana’s "Smells Like Teen Spirit."

After running into Astley backstage at an overseas festival, Grohl pounced on the chance to get him to sing with the band.

“We just learned your song 20 minutes ago. You want to come sing it?”

“(Expletive) yes,” Astley reportedly told Grohl.

“His voice is so strong he almost blew out our monitors,” Grohl added.

Said Bruce Springsteen sent him a handwritten letter after taking in a Foos show — from the cheap seats

It was to praise Grohl’s song “My Hero,” for its human, relatable qualities. “What it’s all about,” Grohl said he wrote.

Broke down 'Best of You' — and sang it a capella for onlookers.

He couldn’t quite pinpoint its enduring appeal but said the Foo Fighters are perpetually bolstered by loud crowd participation and that it’s his favorite part.

This article originally appeared on Austin American-Statesman: 9 things Dave Grohl told Brené Brown, fans at Austin's ACL Fest