Long before they met a couple of guys named Jim Morrison and Ray Manzarek and formed a band called The Doors, schoolmates Robby Krieger and John Densmore used to hit the clubs around Los Angeles, checking out jazz artists like Miles Davis and Wes Montgomery. “I never dreamt that I would be playing any of that music at the time because I was more into folk music, flamenco, stuff like that,” Krieger says today, mentioning that Densmore used to drum with the jazz band at their alma mater, Uni High School. “I hadn’t even learned to play electric guitar yet. But I loved it.”

That love is evident throughout The Ritual Begins at Sundown, Krieger’s ninth solo album and the guitarist’s first in a decade. It’s a deep dive into a jazz side of his playing that, more than five decades ago, he never thought he had in him; Krieger co-wrote eight of the album’s 10 all-instrumental tracks with longtime collaborator Arthur Barrow, who also co-produced the set. The other two selections are new interpretations of “Yes, The River Knows,” a song on The Doors’ 1968 album Waiting for the Sun, and “Chunga’s Revenge,” the title track of a 1970 Frank Zappa solo album.

The Zappa connection runs deep on the new LP. Multi-instrumentalist Barrow played bass with Zappa in the ‘70s and ‘80s, and some of the other contributors—trombonist Jock Ellis, trumpeter Sal Marquez and keyboardist Tommy Mars—are also Zappa alumni. The lineup is filled out by flutist AeB Byrne, saxophonists Vince Denim and Chuck Manning, and drummers Chad Wackerman and Joel Taylor.

Krieger admits he wasn’t a huge Zappa fan back in the mid ‘60s when The Doors and Zappa’s Mothers of Invention were two of the hottest new bands in LA. “I knew him from the Mothers,” he recalls. “We used to play shows with them and he would always come to the Whisky [a Go Go club]. He actually wanted to produce The Doors, but we didn’t really think much of that idea.”

However, in the ‘70s— as Krieger developed his solo career in the wake of Morrison’s death and The Doors’ dissolution—the guitarist began using some of Zappa’s crew. Marquez and Ellis go all the way back to his 1977 solo debut for Blue Note Records, and Barrow, who appeared on Krieger’s 1982 LP, Versions, has subsequently partnered with Krieger on several other projects. Both Barrow and Marquez appear on 2010’s Singularity, Krieger’s previous solo recording.

“Arthur first came out here [to LA] after he graduated music school, with the express idea of getting into Zappa’s band” says Krieger. “That’s where I met him. And I met Sal even earlier. A bunch of us would go over to his house and just learn jazz licks.”

Krieger’s interest in jazz took many years to manifest blatantly in his own work, although it was certainly nurtured by his exposure to inventive guitarists like Larry Carlton and Joe Pass. (“I liked what he did with the Crusaders,” Krieger says of Carlton.”) But even in The Doors, the guitarist and Densmore often brought a defined jazz sensibility to some of the band’s tunes—Krieger’s solos on familiar tracks like “Light My Fire” (which he wrote) and “Moonlight Drive” had a palpable swing to them, and his and Manzarek’s chording on selections like “Riders on the Storm” and “The Crystal Ship” incorporated improvisational ideas from the jazz canon.

Most of the new compositions on The Ritual Begins at Sundown—which gets its title from its Krieger-painted cover art—actually originated as improvisations. “[Arthur and I] just started jamming with some guys,” Krieger says. “He had a studio over in Venice, [Calif.] and we would go down there, turn the tape machine on, and jam and come up with ideas. I think that is a really good way to do it.”

Krieger decided to include the lone Doors cover simply because he felt that it was one of the band’s more jazz-informed efforts. “I’ve always thought that was one of Ray’s best-ever piano parts,” he says. “Arthur transcribed it, note for note, and we had Tommy Mars play it. It’s very jazzy.”

It took Krieger some time, following the end of The Doors, to even allow himself to revisit the band’s material; he needed to distance himself from it in order to help establish his own artistry outside of the band. But now, he says, he’s cool with that legacy.

“For years, I didn’t play any Doors songs,” he says. “But I never realized that The Doors would still be popular after all this time, and then there were all these Doors tribute bands. I knew some of those guys, so I’d go and sit in with them once in a while, and I saw how much fun they were having. So, little by little, I would stick a few Doors songs into my set, and play them instrumentally. Then around the year 2000, Ray and I got back together and just played The Doors, right until the time he passed away [in 2013]. When I play with my own band [the Robby Krieger Band], we do The Doors stuff, and my son Waylon sings with us. It’s fun.”

Krieger has also collaborated with a variety of other artists over the years, both on Doors-related projects and music completely apart from his famed band. Of note, he’s worked with Eric Burdon. “The Doors loved The Animals,” he says. “But who I’d love to play with is Bob Dylan. He was my hero growing up. Now that would be cool.”