If you want to listen -- really listen -- to bluegrass music, one unassuming building stands apart.

"I always say the Station Inn is like an old coffeehouse used to be -- a listening room, and that's exactly what it is," says owner J.T. Gray. "It's a beer joint, it's a club, whatever you want to call it, but it's a listening room. People come here, pay their admission to get in and they want to hear the music."

The Station Inn's humble origins began in 1974 when six pickers decided that Nashville needed a stage to jam.

"There were a couple of bluegrass clubs in town, but they all had a house band that played," says Gray. "All these guys and gals thought it would be neat to have a place where they could have a so-called house band and then have it always open to new pickers who wanted to come in and pick or come to town and join in on the fun."

In 1978, the venue moved from West End to its present location, on the other side of the tracks from downtown. Gray bought the business in 1981 (although one of the founders' ashes is beneath the carpet on stage.) A year later, Gray and Lance LeRoy promoted a show by the Bluegrass Cardinals show and packed the house. Success bred success, paving the way for concerts by the Johnson Mountain Boys, Peter Rowan, Ralph Stanley and the Whites. Bill Monroe used to sit in with the band, no matter who it was.

"I had heard about that place as a kid, and I remember the first time I went -- on a Sunday night," says Alison Krauss. "I was 13, and all the pillars of that community were out that night. It's the place where everybody wants to go play. I don't even know how many times we've played it as a band, but it was a really big deal to get to play there."

Celebrities like Mel Gibson and U2 have come in. So have Sheryl Crow, Robert Duvall, William Shatner and the U.S. Secret Service (with first daughter Amy Carter). Randy Travis celebrated a gold album, Storms of Life, there. Dolly Parton recently surprised the tourists when she jumped on stage to sing with Nickel Creek's Chris Thile. A longtime regular, Vince Gill occasionally joins the Time Jumpers for their Monday night engagement.

Reba McEntire was persuaded to sing "Faded Love" and "San Antonio Rose" with the band during a visit last year. You can bet her impromptu performances were rewarded with a resounding ring from the gigantic cowbell that hovers over the bar. It's a gift from a Swedish fan that is only struck on noteworthy occasions.

"As a rule, people like getting the bell," says Lin Barber, who has worked at the club for 25 years. "They know, normally, when you get the bell, somebody did really well, but they also know when they screw up, you're going to hit it. One of them screws up really good, they look up over there and wonder who's going to slap it."

Even with boarded-up windows and mismatched chairs, Dierks Bentley considers it his favorite bar in Nashville.

"The Station Inn, to me, represents everything that's great about music," he says. "I wouldn't be doing what I'm doing now without the Station Inn. I know that for a fact. I moved to town, and I was discouraged by country music, and I thought it sounded really homogenous. It really wasn't interesting to me at all as a 19-year-old kid. I just wasn't turned on by it anymore.

"So when I got here, I luckily discovered the Station Inn. I walked in there and found guys my age who were tearing up mandolin and banjo, and they could sing so well and sing harmonies. They were so down-to-earth and so friendly and supportive."

The club proudly fosters young talent like Old Crow Medicine Show, the Infamous Stringdusters and Alecia Nugent. Gillian Welch and David Rawlings grew a loyal audience at the bar. Now when they play there, it fills up hours in advance. (No pre-sale tickets are available in order to be fair to everyone.)

"In bluegrass, a lot of the old-timers are moving on, and somebody's got to take their place," Gray says. "I know there will never be music like some of these [historic] bands and brother acts, but they're doing a great job of learning and keeping it going. Some of them may not know the history, but once they learn what they're learning in today's bluegrass market, then they start wondering where this came from. They start researching it and get back to the real roots of it."

Ann Soyars, who books the talent with Barber, adds, "There's no age barrier. I have just as much fun with a 21-year-old -- or more fun -- than the ones I do who are my age."

In the last five or six years, the neighborhood around the Station Inn has dramatically evolved from industrial to in-demand. Luxury condos are going up on every available lot. A sushi restaurant, a super-trendy bar and a warehouse-like rock venue now stand across the street. The extensive martini menus at the nearby swanky bars are in sharp contrast to the "thing of popcorn" at the Station Inn that will only set you back a buck.

"We used to be the only bright lights around here. Not any more," Gray says. "I'd be lying if I said I wasn't concerned about it, but all the development people say they want the Station Inn to stay here and be a part of it because it's been here so long. All we can do is go on what they say they want and hope they live up to what they say, and we can be here. If we're not here, we'll be somewhere close around. But we're planning on staying here for a long time."