J. Ralph confesses to having a major cultural flashback experience while working with the stellar musical lineup he assembled to record songs for a new documentary about autism, “Wretches and Jabberers: And Stories From the Road.”

The remarkably diverse list of participants includes Norah Jones, Scarlett Johansson, Carly Simon, Devendra Banhart, Antony Hegarty, Ben Harper, Vashti Bunyan, Bob Weir, Stephen Stills and Vincent Gallo among many more.

They all signed on to be part of producer-director Gerardine Wurzburg’s film centering on a road trip undertaken by two autistic adult men.

[For the record, Oct. 25, 10:52 a.m.:  An earlier version of this post misspelled producer-director Gerardine Wurzburg's name as Wurzberg.]

“It was the craziest thing,” said Ralph, the New York singer and songwriter who composed scores for two previous Academy Award-winning documentaries, James Marsh’s “Man on Wire” in 2008 and Louis Psihoyos “The Cove” from last year. Ralph’s work on those projects prompted Wurzberg to seek him out to supply music for her exploration of the isolation and alienation that often accompanies autism.

Fistful of Mercy is a new band with an intriguing pedigree, embodied by a trio of distinctive singer-songwriters: Ben Harper, Joseph Arthur and Dhani Harrison. From the first moments of the band's debut performance Tuesday night at The Village studios in West Los Angeles, the sound could be unruly or tranquil, unveiling a modern, quirkier take on the Crosby, Stills and Nash model, colliding folk, blues, eccentric pop and gorgeous three-part vocal harmonies.

The eight-song performance for about 100 invited guests was hosted by KCRW, which is broadcasting the concert at 11:15 a.m. Thursday on “Morning Becomes Eclectic,” previewing material from the trio's new album, “As I Call You Down,” set for an Oct. 5 release on Harrison's Hot Records West label. The songs were agonized and joyous, impulsive and restrained, exploring themes that Harrison listed as “love, God . . .  music, peace.”

During much of the set, the trio sat with acoustic guitars, strumming jangly steel strings, with elegant slices of violin from Jessy Greene, who also appears on the album. Harrison moved to piano for the album's title song, as he, Harper and Arthur sang in warm harmony: “When I fall inside a hole I can't crawl out of / better give up my control as I call you down.”

The group then dove into some tough, agonized blues with “Father's Son,” a song inspired by Robert Petway's ancient “Catfish Blues,” harmonizing as Harper sliced away on an acoustic Weissenborn lap-slide guitar.

The Grammy Museum has landed an impressive roster of artists for its series of question-and-answer and performance sessions in the year since it opened at the L.A. Live complex downtown. Among the participants: Brian Wilson, Smokey Robinson, Annie Lennox, Dwight Yoakam, Herb Alpert, Harry Connick Jr. and Clive Davis, Rage Against the Machine / The Nightwatchman’s Tom Morello and Dave Matthews.

But even in such rarefied company, a former Beatle commands special attention, which helped explain the star-dotted turnout for Tuesday night’s drop-in by Ringo Starr. In the house: guitarist Joe Walsh (an official member of the family since his 2008 marriage to Marjorie Bach, the sister of Starr’s wife, Barbara Bach), George Harrison’s singer-songwriter-guitarist son, Dhani Harrison, E Street Band drummer Max Weinberg, rocker Edgar Winter and Roy Orbison’s widow, Barbara.

“The tickets sold out in eight minutes -- that’s a new record for the museum,” executive director Robert Santelli said during his introduction for Starr, who came as part of promotional efforts for his just-released album, “Y Not.”

Santelli quizzed Starr about serving on the new album as producer for the first time. Looking snappy and trim in a black suit jacket over an Elvis Presley T-shirt he’d just picked up in the museum’s store, dark glasses, black jeans and running shoes, Starr said he had to overcome some trepidation about taking over the production role, but relished realizing that the time had come when “I’ll tell the guitarist what to do.”

He addressed the presence of Paul McCartney on two of the new tracks: singing harmony on the single “Walk With You” and playing bass on “Peace Dream,” a song that invokes the name and longtime peace message of John Lennon. “He understands my drumming,” Starr deadpanned, “because we used to play together.”

The lights are turned down low at Eldorado Studios in Burbank, where Ben Harper is sitting with a mahogany lap-slide guitar, plugged into a custom amplifier set to burn. It's nearly 3 a.m. and Harper is lost in the moment, playing "Why Must You Always Dress in Black," five minutes of smoldering madman blues with a bit of Texas in the grooves. The singer-guitarist is bent over his instrument, effects pedals beneath his feet, eyes shut tight as he shouts an uneasy "a-hey-hey!"

The session is in late September, 11 days into the recording of "White Lies for Dark Times," Harper's ninth studio album and the first with his new band, Relentless7. The 11-track collection, which jumps from heavy rock to soul to graceful acoustic balladry, is set for release Tuesday on Virgin Records.

At 39, Harper is a journeyman rocker with a sizable following and two Grammy awards, but he's found new inspiration in the company of Relentless7 guitarist Jason Mozersky, bassist Jesse Ingalls and drummer Jordan Richardson, all from Austin, Texas, and late transplants to Los Angeles.

"For the first time in my musical life, I'm in a creative environment where it's taking all of my senses and perception to keep up," says Harper, who has put his longtime band, the Innocent Criminals, on indefinite hiatus. "I don't want to make compliments about my new band in a way that seems like a put-down to my old band . . . but I gotta say, right now I'm in a group where I am fighting for my life. I'm practicing on my days off. I'm spending more time writing than I ever have. And I'm loving it."