Bluegrass series stays underground for fifth season

The Bluegrass Underground shoots its fifth season for PBS this weekend in McMinnville's Cumberland Caverns. The subterranean concert series began in 2008 (and found its way to public television three years later), but it's been in the works since the Pliocene Era.

Three and a half million years ago, two rivers — one flowing north-south, the other going east-west — intersected, slowly carving a natural amphitheater, the "Volcano Room," out of stone 333 feet below the ground that would eventually be named Tennessee. Bluegrass Underground founder Todd Mayo first got the idea to stage concerts in the Volcano Room during an impromptu tour on Memorial Day 2008. Although he loved roots music, Mayo worked in the advertising industry and had no experience in staging concerts.

"I hadn't even booked a bar mitzvah," he laughs.

To test the cave's acoustics, Mayo brought sound engineer Phil Harris and a group of acoustic musicians down into the Volcano Room. They soon found out that the room was a stellar location in which to make music: It resonated at only two frequencies, and despite the uneven stone surfaces, there was no echo.

Story continues after video

Mayo then partnered with WSM, who agreed to broadcast the show on the radio, and tapped gritty bluegrass band The SteelDrivers to play the inaugural Bluegrass Underground concert. On the day of the first show in August 2008, Mayo met Todd Jarrell, a freelance writer and public television producer, who was there to cover the event for NPR. The two men immediately hit it off. Soon they formed their eponymous production company, Todd Squared, to bring PBS a show that Mayo described as " 'Austin City Limits' meets 'Nova.' "

"The Bluegrass Underground is this perfect marriage of the two things about which Tennessee can be most proud: amazing natural beauty paired with profound musical culture," Jarrell says.

While the concept of a cave concert sounds primitive, the reality is anything but. The show, which is filmed in high definition, requires nine cameras along with a world-class sound system and lighting rig, plus a generator to power all of that equipment. Loading all the gear into the Volcano Room is an exhausting process that takes three days: cameras, cables, catering and chairs get transferred from semi-trucks to small garden trailers pulled through the cave by four-wheelers. It's an exhausting, repetitive process that leaves the crew of nearly 100 people dripping in sweat despite the constant 56-degree temperature underground. After taping an entire season over the course of a weekend, the crew hauls everything out of the cave overnight.

Story continues after video

There's no backstage and no green room, just 32 miles of cave that stretch above and behind the audience. The crowd sits on folding chairs and perches on rocks. Occasionally, one of the bats that calls Cumberland Caverns home makes an appearance. Despite the 40-foot ceiling, it's an incredibly intimate and gorgeous listening room that captivates not only the audience, but the musicians, too.

"Playing there is unlike any other experience I've ever had," says Eric Gibson, whose band The Gibson Brothers appeared on BGU in 2014. "(Brother and bandmate) Leigh was a little nervous about being so far underground, but that cave's been there forever. You're more likely to get hit by an asteroid above ground than have anything happen down there."

This weekend, cave dwellers will see a diverse lineup of performers that ranges from Lee Ann Womack to Amos Lee to Robert Earl Keen. Tickets sold out 10 minutes after they became available, thanks to a constantly growing legion of fans — made up of not only returning guests, but roots music aficionados from around the world who consider a trip to the cave an item for their bucket lists. One of Mayo and Jarrells' favorite fan stories is about a woman living in Dubai who sold her car so that she and her boyfriend could travel to Tennessee and see singer Amy Lee (of Evanescence) play the cave.

"She's taking the bus in Dubai now, but she's got unforgettable memories," Mayo says.

Story continues after video

CAVE MUSIC HALL

Bluegrass Underground by the numbers: Here's what it takes to stage concerts in a cave:

•100-person crew

•700 folding chairs

•9 HD cameras requiring 5,000 feet of fiber optic cable

•175 kW generator, requiring several hundred gallons of fuel daily

•40-foot motorized lighting truss, which must be suspended from the ceiling by a 42-foot lift

•1 mobile video lab, parked outside the cave opening

•1 $500,000 PA and stage monitor system

MONTHLY CONCERT SERIES (airs on WSM 650 AM)

•April 18 — Russell Moore & IIIryd Tyme Out

•May 2 — Frank Fairfield, Trace Bundy

•June 27 — Ben Sollee, Woody Pines

•July 19 — The Annie Moses Band

•Aug. 22 — Anniversary Show: The Volunteer String Band, Jimbo Darville and The Truckadours

•Sept. 5 — Lonesome River Band, Old Salt Union

•Sept. 26 — Taarka, Front Country

•Oct. 3 — Ray Wylie Hubbard

•Nov. 21 — Mountain Heart, Emi Sunshine