After spending a recent Friday afternoon watching his daughter splash around in a backstage kiddie pool, Jason Isbell took the Merriweather stage with a huge smile on his face. The Nashville-based singer-songwriter quickly gushed about the surroundings.

“We never thought we’d get to headline a venue like this,” Isbell said. “The place keeps getting better and better every time we come back.”

It’s a sentiment Merriweather officials hope will be common among returning artists.

A recent tour of the venue revealed the major renovations that Canfield said were long overdue. For fans, they include new bathrooms, more food options and a larger stage house capable of accommodating elaborate productions that previously wouldn’t have fit at Merriweather. (Canfield cited the Chainsmokers, who performed there in late May, as a recent example.)

There’s also the new $6.6 million Chrysalis amphitheater, located about 200 yards from the main pavilion. In the midst of trees, the bright green sculpture adds a more intimate stage that will host the band Greensky Bluegrass on July 22 as one of its first performances.

Top left: Ticket stubs from a performance by the Washington National Symphony featuring Van Cliburn on July 6, 1968. Tickets that season cost between $3.50-$5.50. Top right: A poster from the Virgin Mobile FreeFest 2009. Bottom: A promotional schedule from the 1969 Merriweather Post Pavilion season. Though not listed, The Who and Led Zeppelin performed on the same bill on May 25 that year. (Courtesy of Merriweather Post Pavilion)

What could have the most significant impact for Merriweather’s future is the space most fans will never get to see: backstage. What used to be a quaint area of double-wide trailers for artists and their teams has been transformed into a sprawling, 15,000-square-foot complex with 11 dressing room suites that can comfortably accommodate artists and families. It can also host festivals with larger lineups, which Merriweather plans to book more of in the future, Hurwitz said.

Not all music fans love the growing emphasis on festivals.

“That’s more for a younger generation,” said Karr, who believes the all-day events can often contribute to increased drunkenness and drug use among patrons. “I’d rather see them pay more money for a really stellar act or two than the multiple acts, but I understand that it’s a business.”

In 2014, two males, ages 17 and 20, died of apparent drug overdoses while attending an electronic dance music festival at Merriweather. Police, who said MDMA was the most commonly used drug at the show, also issued 50 underage drinking citations that day. In a statement released shortly after, Hurwitz mourned the deaths, stating, “We need to work on convincing kids that those pills they put in their mouth could kill them.”

Another event, the genre-spanning Sweetlife Festival in 2015, sparked noise complaints from nearby residents; Merriweather installed new sound monitoring systems the following year in response.

Summer festivals of all genres, though, have become hugely popular, and Merriweather’s renovations reflect a venue ready to host more. There’s now a large dining room, cabanas for private massages from on-site masseurs and a heated swimming pool that artists have already used during post-performance parties.

“We were 10 or 15 years behind when we should have [renovated],” Canfield said. “A couple people summed it up that we went from a crusty old summer camp that had been neglected to a Four Seasons.”

To compete with corporations with bigger budgets and resources, Merriweather hopes its updated amenities create a welcoming environment that will make a lasting impression on artists. The aim is to give them reasons to come back, Hurwitz said.

Earlier this year, Hurwitz and I.M.P. signed a 40-year lease to continue to operate Merriweather.

The long-term commitment has allowed Hurwitz and his team to continue to create the type of music experiences generations of music fans have come to expect from Merriweather. A great show here has a spirit to it that’s hard to describe, but it’s palpable to the audience when everything clicks. That’s what Hurwitz is after.

“We have this wonderful facility, but all of this stuff would be no good if you didn’t run it right,” Hurwitz said. “I’m just so happy that I’ve been able to keep this wonderful group of people together and build on it and create this vibe. Vibe is everything.”