IT'S odd how rain irons out the idiosyncrasies of locality, and turns even the most distinctive of American cities into Anytown USA.
The rain's falling steadily in Nashville, and as I step from the taxi outside Dan Auerbach's Easy Eye studio, the drizzle-flecked neighbourhood could as easily be in New Jersey or Chicago.
I can't help but feel slightly disappointed.
I've lived for years in the Nashville of my mind, its streets packed with cowboy-hatted minstrels toting guitar cases to gigs, and when I finally get here, it's shut.
Yet this is the city the Black Keys duo of Dan Auerbach and Pat Carney chose to make their home, after spending their earlier lives in the industrial heartland of "rubber city" Akron, Ohio, whose tyres kept the American Dream rolling.
The Black Keys' most recent album, El Camino, makes oblique reference to the notion of movement at the heart of the American Dream.
Spanish for "the road" or "the way", it's a nod to the pilgrimage of dues-paying, the months of one-night-stands in tiny Midwest towns which hone raw talent into rock 'n' roll gold.
The fanciful romanticism of the title is bathetically offset by the cover image of an anonymous people-carrier - yet this, it transpires, is the very vehicle in which the group toured America, developing their skills and building their reputation.
"We toured in that little mini-van for the first year and a half," says Pat Carney, the band's gangly percussive powerhouse.
"I would do all the late-night drives, and Dan would do all the daytime driving."
This division of labour is something that has helped the duo remain focused and efficient.
"The way it was divvied up was that Dan would write the lyrics and sing, we would write the music together, and I would record it," says Carney.
"We basically ran it like a little coffee shop, there were a set of rules about how we'd operate. Our first few shows we got paid about $10, after that we started asking for $50, $100, and so on - the goal was for us each to make about $150 a week, so we could pay our way, and we were able to do that within four months of our first show. And we've supported ourselves ever since."
Over time, however, roles have shifted slightly, and now instead of Carney recording the band in his basement home studio, it's Auerbach who has become the self-proclaimed "studio nerd", kitting out his Nashville studio with a muso's wonderland of antique gear.
Piled up against the walls are mellotrons, chimes, tympani, and weird, obscure keyboards like optigan and chamberlin.
An ancient Altec solid-state mixing console sits atop a Wurlitzer piano, awaiting renovation.
And an entire side-room is populated by racks of guitars, not just the usual Fenders and Gibsons.
"I like a lot of 60s Japanese and American off-brands, that's what I gravitated to," explains Auerbach.
"The guitar I used on the first record was a Harmony Stratotone, and I've used it on every single Black Keys record since."
He takes the guitar down and hands it to me. It's a utilitarian instrument from the 1950s, built around a single solid plank running all the way from neck to head, but it does what Auerbach wants.
"I'll use any guitar," he says.
"I like the gear stuff, it's fun; but I do know that none of the gear matters - in the end it's all about the musicians and the music. A great player can make any of those things sound great."
And to give him his due, Auerbach makes a great racket with whatever guitar he uses, employing a blend of lead and rhythm modes that recalls the great Wilko Johnson from Dr Feelgood, and is likewise rooted in the blues.
When he was growing up, Auerbach's dad would play lots of country blues by the likes of Son House and Robert Johnson, and he naturally gravitated in that direction.
"I started going backwards, searching for sounds," he says.
"I was listening to a lot of, like, early Memphis blues. And then I discovered the Fat Possum label, and Junior Kimbrough just blew me away."
He started playing solo gigs in cafes and clubs, before hooking up with drummer Carney, who lived a block or two away. Carney, however, knew nothing of the blues.
"I've always been more drawn to rock 'n' roll," he says.
"When we first started the band, I had never heard of Mississippi Fred McDowell; but then, Dan had never heard the Stooges, or Led Zeppelin! At first there was a bit of resistance from both of us."
But, gradually, the duo found enough shared touchstones on which to build their own sound. They both had uncles working on the outsider fringes of rock, who helped broaden their musical outlook.
Auerbach's uncle Robert Quine was a former member of proto-punk band the Voidoids, and had worked with Lou Reed in New York, where his idiosyncratic style gained him the sobriquet "The King of Skronk Guitar"; while Carney's uncle Ralph Carney was for years Tom Waits's go-to saxophone guy.
"When he heard I was getting into music, my Uncle Ralph got excited, and he would send me tapes of weird albums like Can's Tago Mago," says Carney.
"If it was anybody but my eccentric saxophone-playing uncle, I would have hated it, but I forced myself to get into it."
Years later, his uncle's influence would pay dividends, as Carney's "really shitty version of the beat from Can's Vitamin C" became the rhythmic undercarriage which carried the Black Keys' biggest success, Tighten Up, into the upper reaches of the US Top 40.
It had been a long time coming. Although their blues-rooted rock had frequently drawn comparisons with the White Stripes, the Black Keys had struggled to make the same kind of crossover into the mainstream.
Eventually, in lieu of radio airplay, they began licensing tracks for use in movies, videogames and commercials, and found it was a potent promotional tool.
"We really noticed a difference when we played live," says Auerbach.
"That song off our first record, I'll Be Your Man, got licensed as theme song for an HBO show, and a couple of months after it started airing, we began getting really good responses when we played it live. The record came out seven years before!"
That 2002 debut, The Big Come Up, was the first of a series of self-produced albums mostly recorded in Carney's basement (except for 2004's Rubber Factory, recorded in a factory warehouse, since demolished).
Thanks to diligent touring and licensing, each eventually sold around 300,000 copies.
Then for 2008's Attack & Release, they were lured into a proper studio by producer Brian "Danger Mouse" Burton, and their raw blues-rock blossomed into a diverse range of sonic hybrids.
"He helped us filter our ideas, kept us moving forward," says Auerbach.
"He would throw in suggestions, and he has little studio tricks, atmospheric touches that he's known for. We were listening to all kinds of music by then, lots of old Japanese and South American psychedelic records, when we made that record. And it made a huge sonic difference using a proper studio."
Burton's influence persisted through their million-selling, Grammy-winning Brothers - his input was crucial to the breakthrough track Tighten Up - and into El Camino, for which he became an equal team member.
"We didn't prepare anything for El Camino," says Auerbach.
"We just all showed up here at noon on the first day, started listening to records, and getting inspired by stuff we were listening to - rockabilly stuff, the Cramps, Johnny Burnette, and bands like the Sweet, the Clash - all music stemming from that early, no-frills rock 'n' roll. We started jamming, something would catch our ear, and we'd start building on it, consciously aiming for the simplicity of the records we were listening to."
The resulting parade of infectious, 1970s-flavoured guitar and organ riffs fronted by soulful harmonies, is the most complete realisation so far of the band's theoretical "perfect album" formula, which they have always believed should be 11 tracks long, running about 37 minutes.
And it sounds absolutely massive.