She's anything but normal when she starts singing in her raw, soulful wail, and along with her Southern fried rock, blues and gospel cohorts - guitarist Heath Fogg, drummer Steve Johnson, and bass player Zac Cockrell - comes up with a passionate, and at times visceral, old-school style of rock'n'roll.
Former White Stripe Jack White, who released his debut solo album this week, liked what he heard and earlier this year selected two of the band's songs to kick off his Third Man record label's live seven-inch series of releases.
Just don't call them retro soul.
"I think the thing is," says Howard, "we're just playing what we know how to play, and I think that's why we get along - there's no one trying to boss anyone else around and we appreciate what each other does.
"But I just tell people it's rock'n'roll ... just don't expect everything to be pretty and sparkly and polished. [In concert] there are strings breaking all over the place, there's sweat and yelling, and there's mic stands falling over," she laughs.
Thinking back she also remembers when the band first started playing together they "wanted to be like throwback country, like Patsy Cline, and throwback rock'n'roll, like Chuck Berry".
But then throw in some T Rex, even a little bit of Black Sabbath, and some fired-up soul and gospel music and you have something like the sound Alabama Shakes create.
Many of the songs on Boys & Girls are inspired by Athens, and Howard's formative years growing up there. She wrote songs such as Goin' To The Party ("If someone drinks too much and they look at someone the wrong way they get into a fight. Just like anywhere," she chuckles) and the title track in her teens. Though, she says, "Boys & Girls, the song, never became a real thing until we all started working on it and performing it".
"It's a song about growing older and trying to fall in with how things are supposed to be. A lot of the songs [on the album] relate to growing up, losing that innocence, and trying to figure out things that are happening around you."
Songs like Hold On and Hang Loose simmer along simply, but they are played with an unmoving staunchness, and then there's the gritty bluesy groove of Be Mine and the shredding serenade of Heartbreaker is Howard at her best.
She has always sung, and remembers getting together with her cousin to sing TLC and Destiny's Child songs. When she was 13 she started taking music more seriously and writing her own songs - and the now 23-year-old hasn't stopped since. "And it's always been quite unique because I was never taught how to use my voice [properly]. And I'll tell you one thing, I went to a vocal coach one time because I was having voice trouble because I was singing more than I ever had, and she pretty much told me I was doing everything the wrong way. Which is funny because I don't know any other way."
You should send her a copy of the album then?
"Oh, she wouldn't like it. She was classical trained. I only went to see her once," she hoots.
It was living in little old Athens that inspired Howard and her high school mate Cockrell - "He would come over during the week. He was my songwriting partner, and we would just practise until dark." - to start a band.
"There's not a whole lot going on here, and if you wanna have fun it's kind of up to you. You have to be creative and come up with something yourself - like having a band play over at your house. There's not much of a nightlife. It's pretty boring, and so that's mostly why I started playing music in the first place."
As well as meeting Cockrell at high school, she also met Fogg and Johnson and they bonded through a shared love of music. They cut their teeth on playing gigs wherever they could get them, including in the hallway at parties (a memory that's recalled on Goin' To The Party).
"The music came first and the friendship followed," says Howard, who counts herself lucky to have hooked up with her bandmates at all.
"In Athens there are hardly any musicians so we were just ecstatic to have someone to play with.
"And in the beginning there was no one listening, and now people are listening to us - it's actually incredible."
Lowdown
Who: Alabama Shakes
Line-up: Brittany Howard (guitar/vocals), Heath Fogg (guitars), Steve Johnson (drummer), and Zac Cockrell (bass)
Debut album: Boys & Girls, out now
-TimeOut
