Emmylou Harris, Sheryl Crow and Elvis Costello Honor Gram Parsons at the Troubadour

Gram Parsons entered the Rock & Roll Hall of Fame this week, and on Wednesday night the Troubadour in Los Angeles answered with "A Song for Gram" — a tribute concert starring Emmylou Harris, Elvis Costello, Sheryl Crow, the Black Crowes and more than a dozen acolytes of the late "cosmic American" pioneer.

Parsons died in 1973 without commercial success, but his blend of country, soul, rock and folk has shaped generations of musicians. Wednesday's lineup proved the point, mixing collaborators (Harris), longtime champions (Costello, Crow) and younger devotees like Jesse Welles, Margo Price and Madison Cunningham. Polly Parsons, the singer's daughter, produced the show with Vector Management, the Rock Hall and Rolling Stone co-editor in chief Shirley Halperin. The house band was Beachwood Sparks.

What did the night actually sound like?

Polly Parsons opened with a speech framing her father's vision. "He looked at the landscape of American song," she said, "and saw a map where all the roads connected … It was a seamless tapestry that wove together the deep, raw heartbreak of traditional country, the spiritual urgency of soul, the gritty energy of rock, and the storytelling of folk."

The set drew from every chapter of Parsons's short catalog: his solo albums, the Flying Burrito Brothers, the Byrds, and his early days with the International Submarine Band.

Second-generation kin carried the early stretch. Grahame Lesh, son of Grateful Dead bassist Phil Lesh, opened the music with "Luxury Liner." Harper Simon, Paul Simon's son, delivered "One Hundred Years From Now" and, later, "Still Feeling Blue."

The Head and the Heart harmonized through "Brass Buttons" and "A Song for You." Jesse Welles played a Dylanesque solo "Hickory Wind" — harmonica included — and his duet with Margo Price on "Return of the Grievous Angel" stayed so faithful to the 1974 original with Harris that the pair seemed to walk straight off the record. Madison Cunningham hit a near-impossible upper register on "Hearts on Fire" and turned in the night's best guitar work, nylon-string fingerpicking on "You Don't Miss Your Water."

Why the Troubadour mattered

The venue itself was honored by the Rock Hall earlier that same day as a landmark music venue. Parsons spent his later years living and recording in Los Angeles. The Black Crowes' Chris Robinson reminded the crowd that Parsons grew up in Georgia, the band's home state, before "Lazy Days" swaggered and "She" found the Robinson brothers trading verses.

The emotional peak was a surprise: Sheryl Crow joined Harris for "Juanita," a song they recorded for 1999's Return of the Grievous Angel: A Tribute to Gram Parsons. Crow describes singing it with Harris as being "like heaven." The room went silent. At soundcheck, Crow had called sharing the stage "epic," to which Harris replied, "You're no slouch yourself."

Harris served as the night's performer emeritus, singing "Sleepless Nights" with Costello, "The King of Broken Hearts" with Jim Lauderdale — a song they recorded as a duet in 1991 — and "Love Hurts" with Mike Campbell, who conjured his late Tom Petty bandmate. Grace Potter closed the main set with "Hot Burrito #2," handing out actual hot burritos to front-row fans after nearly three hours on their feet.

Two group sing-alongs ended the night: "Wild Horses," which Parsons famously recorded before the Rolling Stones made it a hit, and "In My Hour of Darkness," led by the younger performers as dozens leaned into the cosmos — sending one of rock's most underappreciated voices into the stratosphere at last.

Full set list: "Luxury Liner" (Lesh); "Christine's Tune" (Price); "Hearts on Fire" (Cunningham); "One Hundred Years From Now" (Harper Simon); "Brass Buttons" and "A Song for You" (The Head and the Heart); "Hickory Wind" (Welles); "Return of the Grievous Angel" (Welles, Price); "Wheels" (Price); "Big Mouth Blues" and "That's All It Took" (Costello, Lauderdale, Price); "Hot Burrito #1" (Costello); "Sleepless Nights" (Costello, Harris); "Ooh Las Vegas" (Potter); "Still Feeling Blue" (Harper Simon); "You Don't Miss Your Water" (Cunningham); "$1000 Wedding" (Lesh); "Streets of Baltimore" (Lauderdale, Costello); "The King of Broken Hearts" (Harris, Lauderdale); "Juanita" (Crow, Harris); "Love Hurts" (Harris, Campbell); "Lazy Days" and "She" (Black Crowes); "Hot Burrito #2" (Potter); "Wild Horses"; "In My Hour of Darkness."