Because Swamp Dogg’s art conceals his mastery, you might be slow to notice how effortlessly the singer, pianist, songwriter and producer upends the conventions of soul music on his new full-length Sorry You Couldn’t Make It. Recorded in early 2019 at Nashville’s storied Sound Emporium studio with Poliça leader Ryan Olson producing, Sorry is technologically evolved pop — its sonics are inseparable from its themes. Perhaps by accident, the album sums up the career of one of pop’s greatest conceptualists. Swamp Dogg is the sobriquet of Jerry Williams Jr., who learned his craft as a journeyman soul musician in the late ’60s before inventing his alter ego in 1970. Sorry is an addictive 38 minutes, and it marks a late moment in the history of country-soul crossover, a genre Williams helped invent 50 years ago.

Sorry You Couldn’t Make It once again pairs Williams with Olson, who reinvented the Swamp Dogg concept on 2018’s Love, Loss, and Auto-Tune. On that album, Olson used Auto-Tune to brilliant effect, and Williams pulled off a sparkling piece of post-modernist country, “I’ll Pretend.” Love, Loss, and Auto-Tune situated a great musical thinker in technological space. Williams’ new record, which sports two affecting vocal turns by the late John Prine, builds upon the country underpinnings of his previous work, but Olson finds ingenious ways to present his songs.

I caught up with Williams via phone in May at his home in Southern California, where he’s lived since 1978. As Swamp Dogg, Williams has made 25 albums since his 1970 debut Total Destruction to Your Mind, including 2014’s The White Man Made Me Do It, and he’s produced countless records by all manner of pop and soul artists — his ’60s and ’70s work with singers like Doris Duke, Freddie North and Arthur Conley constitutes a significant addition to the soul canon. I asked him if he had needed a push into a new direction when he made Love, Loss, and Auto-Tune.

“I’m gonna say yes to that,” Williams says after a long pause. “I had exhausted all of my thoughts and avenues in reference to how I should be cut, and what I could appeal to the public with. And so, I hooked up with Justin [Vernon] and with Ryan, and I left it all in their hands. I didn’t get involved at all, which is different when you’ve been doing your stuff your way.”

With its assured simulations of Muscle Shoals-Memphis soul, Sorry You Couldn’t Make It at first seems less audacious than Love, Loss, and Auto-Tune, but the two albums bookend each other nicely. Sorry refracts Williams’ songwriting into patterns that are both organic and artificial. Along with the aforementioned Bon Iver singer and songwriter Vernon and Nashville ax man Jim Oblon, Olson assembled a band for Sorry that included keyboardist Derrick Lee, a longtime fixture in Music City’s gospel and country scenes.

Lee, who moved to Nashville in 1976 from Newark, N.J., helps define the sound of Sorry, moving from country piano to R&B-flavored Fender Rhodes. As he says, he wasn’t familiar with Williams’ work, but he felt the music.

“When he heard me playing, he just kind of gravitated to me,” Lee says. “He just kind of connected, and so he wanted me to just do it the way I felt it, more so than me trying to interpret where he was coming from.”

Also on board were synth player Moogstar (whom you’ve heard on records by Zapp and Cameo) and singer Jenny Lewis, as well as Poliça’s bassist Chris Bierden and singer Channy Leaneagh. Sorry grooves like an updated version of a ’70s album by Dan Penn or Jim Ford, and it certainly recalls the country-pop-soul style Williams created on classic Swamp Dogg albums like 1981’s I’m Not Selling Out / I’m Buying In!

Still, the theme of both Love, Loss, and Auto-Tune and Sorry You Couldn’t Make It is the emotional aftermath of loss. For the 2018 album, Olson repurposed Williams’ music, creating a nuanced backdrop that represents a departure from Williams’ previous — and more traditionally produced — records.

“He sent me this album he had completed, basically,” Olson tells me from his Minneapolis home. “And I said, ‘I’ve got some ideas,’ and I just kinda fucked with it for, like, a year-and-a-half, two years, off and on.”

Olson chose the songs for Sorry from Williams’ catalog of unrecorded material, which Williams says numbers somewhere around 900 tunes. Sorry is a bracingly experimental record, right down to one of its key drum sounds, which is a mutated sample of Williams’ demo of “Please Let Me Go Round Again,” one of the songs featuring Prine. On “Memories,” the other Swamp Dogg-Prine duet on Sorry, the performance seems to decay, as if technology is eroding the memories both men are clinging to.

“At the end of ‘Memories,’ where it kind of corrodes into a broken cassette, we mixed it down to a cassette,” says former Nashville studio owner Mark Nevers, who engineered the Sound Emporium sessions and mixed Sorry at his Beech House Recording in South Carolina. “Then we pulled at the tape and crumpled it up, and then wheeled it back in.”

It’s a disquieting moment on a record that ambles in the slipstream of soul music’s history. Sorry You Couldn’t Make It may be Swamp Dogg’s most evocative, listenable and mysterious album to date. That’s saying a lot for a confoundingly prolific artist who has amassed a huge body of work since the 1950s.

Swamp Dogg

Now 77, Williams was born in 1942 in Portsmouth, Va. He absorbed country music on the radio, listened to jump-blues artists like Wynonie Harris and Amos Milburn, and began hustling in New York in the mid-’60s. He had a minor R&B hit with 1965’s “Baby, You’re My Everything,” but it was an unsuccessful — and demeaning — year as an A&R specialist and producer at Atlantic Records in 1969 that helped turn Williams into Swamp Dogg.

The Swamp Dogg albums Williams cut in the ’70s adapt every kind of American music that intersects with soul. On funny, outrageous songs like 1974’s “Did I Come Back Too Soon (Or Did I Stay Away Too Long)” and 1976’s “Or Forever Hold Your Peace,” Williams examines the wild morality of the ’70s as a hapless everyman who can’t stop looking at what he’s not supposed to see. The all-purpose African American pop adept filled his early records with covers of songs by Mickey Newbury, Bobby Goldsboro, The Bee Gees, Joe South and — perhaps most famously — John Prine.

“I heard it, and I took a couple of copies of it home,” Williams says about Prine’s 1971 recording of “Sam Stone,” which got the Dogg treatment on 1972’s Cuffed, Collared & Tagged. “After I listened to it, I said, ‘This has got to be one of the greatest songs I ever heard in my life.’ ”

Williams’ version of “Sam Stone” erased barriers he knew were too porous to keep anything pure for long. For the sheer range and consistency of his body of work, Williams belongs in the pantheon of American songwriters that includes Randy Newman and Allen Toussaint, and his production skills include a feel for post-jump-blues horn arrangements that always swing.

Sorry is gently surrealistic and highly allusive, as on “I Lay Awake,” a beautiful track worthy of any country-soul record ever made. Williams’ duets with Prine make their case for male bonding in the face of existential despair, but it’s clear that Williams misses his first wife, Yvonne, who died in 2003.

“A lot of my stuff is for her,” he says, carefully. “Most of my stuff is inspired by her. I look at her picture every day, and think of her. I’ll never get over her.”