There he was, out on Van Ness at 10pm: a man in a mohawk, hiking boots, cutoffs, sunglasses, and a Social Distortion jacket. Not a particularly unusual sight in San Francisco — except that minutes before, he’d been politely applauding a pianist and composer with a string quintet.

With the way things are going for music in movies, such sights may become more frequent. On Tuesday and Wednesday, Jóhann Jóhannsson and Hans Zimmer performed not at Davies Symphony Hall but at the Regency Ballroom and the Bill Graham Civic Auditorium, respectively. It seemed almost too surreal: two award-winning film composers, performing on back-to-back nights in San Francisco, at venues that normally host EDM, metal and hip-hop acts.

Without wanting to actually type the embarrassing phrase “Are film soundtrack composers the new rock stars?,” I can’t help but wonder, well… are film composers the new rock stars?

Judging by Hans Zimmer’s sold-out show on Wednesday night (and the people begging for tickets on the sidewalk outside), the answer would be yes. Known for his film scores for The Dark Knight, The Lion King, Interstellar and others, Zimmer’s two-and-a-half-hour extravaganza — a hit at Coachella three nights prior — contained every kind of rock ‘n’ roll excess, with constant flash, dazzle and bombast.

This was not Hans Zimmer Conducts Symphony Orchestra in an Evening of Collected Works. It was electric cello epics performed in bare midriffs and punctuated by hair whips; three drummers in a triple drum solo that could bring Keith Moon back from the grave; a 19-piece band with a choir and pickup orchestra playing more notes per second than a Frank Zappa / Yngwie Malmsteen shred-off.

Like the superhero films Zimmer often scores, the performance was decidedly unsubtle. One minute, the cluttered bonanza resembled the metal-laden prog-spazz of the 1990s band Mr. Bungle, and the next, it careened entirely into realms previously occupied by John Tesh or Yanni. It was proficiency and virtuosity on crack, an assault on the senses. For his part, Zimmer — with a martini next to plastic bottles of Gatorade atop his piano — egged louder and louder chants out of the crowd, who eventually called for an encore with a canvas of thousands of cell-phone flashlights.

By the time Zimmer finished the show, sitting alone and playing the spare piano theme of “Time” from his greatest soundtrack, Inception, with near-silence in the room, it felt beautiful, pure, and after the previous two hours, completely foreign.

This is Zimmer’s first full-scale tour of the United States, complete with $35 T-shirts and $20 programs. It’s been so successful that he’s coming back to the Bay Area, at the Greek Theater, in August. Could any other living film composer pull off a tour like this, selling out 7,000- and 8,000-capacity venues? John Williams, certainly, could do a Star Wars-pegged blowout, or possibly Danny Elfman, with the right stage set. The fact is that over the years, even the movie composers with huge cult followings — Bernard Herrmann, Nino Rota, Ennio Morricone, Angelo Badalamenti — have been, on a pop-culture scale, niche interests at best.

That’s slowly changing. Soundtracks, particularly video game soundtracks, have seen a big boost in the resurgent vinyl format. Last year, horror movie icon John Carpenter proved that composers can go on tour and sell out rock halls. If the trend continues, with any luck, composers like Zimmer won’t have to propose silly ideas like “let’s see if we can make a cello concerto rock” to attract crowds; they’ll be able to let the music breathe. Like Jóhann Jóhannsson.

Jóhannsson is an Icelandic composer best known for his scores to The Theory of Everything, for which he won a Golden Globe, and more recently, Arrival; he’s also scoring the highly anticipated Blade Runner 2049. His booking at the Regency Ballroom was a curious one: a venue where I’ve seen hip-hop artists like Chance the Rapper and Future as well as punk bands like Against Me! and Desaparecidos. Jóhannsson’s latest album of original music, Orphée, is on the globally respected classical label Deutsche Grammophon, and so Tuesday’s show felt a little like Charles Ives booked at CBGB.

The crowd for Jóhannsson was younger and more diverse than Zimmer’s, but also more restrained and attentive. With members of the American Contemporary Music Ensemble — a string quintet augmented by an electric bassist/noisemaker — Jóhannsson alternated between piano and keyboard and, between pieces, switched the prerecorded samples on an old analog reel-to-reel tape machine.

Jóhannsson’s music combines both doom and uplift — a celestial sound with just enough discomfort to make one sink in their own seat, unsure of the mere act of taking up space. The silence in the ballroom added to the feeling. One could hear sheet music being turned, or the thwack-thwack-thwack of the reel-to-reel tape unspooling and hitting the heads of the machine. Songs bled into each other. No one clapped until the end.

This was far from the ostentatious showmanship of Zimmer’s tour, but more hopeful, in a sense. No one needs to lean in to Zimmer’s music, because it does all the listening for you. Jóhannsson, on the other hand, draws an audience in to his strange, mesmerizing world, wresting the most out of his notes by playing less of them. And where Zimmer finally got quiet at the end of his set, Jóhannsson finally got loud: a cacophonous crescendo that rumbled and screeched until a sudden cease-fire, met, at last, with a wild standing ovation.

If soundtrack composers continue to cross over, it will be figures like Jóhannsson keeping the trend honest. On the sidewalk afterward, lots of ohmygodthatwasamazing could be overheard from wide-eyed audience members — including the one in a mohawk and Social Distortion jacket. A similar reaction is likely for the upcoming reboot of Blade Runner, due in October, the original Vangelis score of which is a favorite of goth and electronic music fans. No doubt, Jóhannsson’s crowds will grow.