‘Bop Spotter’ Is a Secret Phone Eavesdropping on the Mission’s Music Tastes

Anyone who’s ever spent any time in San Francisco’s Mission District can tell you of its noisy, eclectic joys. I’ve lived in the neighborhood for two decades. While the sounds of Norteño, hip-hop and reggaeton dominate my block on the weekends, there’s also never a shortage of pop tunes sung by drunk ladies at high volumes, ’90s nu-metal choruses being yelled from cars, and — my personal favorite — the guy who regularly drives up 26th Street blasting Phil Collins.

Now, a 22-year-old New York City transplant named Riley Walz is using Shazam and a strategically placed, solar-powered Android phone to create an archive of the neighborhood’s musical selections. He calls the project Bop Spotter — a play on words inspired by ShotSpotter, surveillance technology used by law enforcement (including SFPD) to capture gunshots.

“I just thought it was kind of a funny little joke to pick up songs instead of gunshots,” Walz tells KQED Arts.

Walz, who lives somewhere between the Castro and Twin Peaks, dropped out of college and moved to San Francisco in January 2023 to co-found an AI-related start-up with his best friend. He immediately fell in love with the Mission District.

“It’s such a unique neighborhood with so many cultures and so much depth,” Walz says. “And as far as I can tell, most of the music [you hear in the Mission] is being played on the street. I use Shazam all the time — at parties, on the street, in stores. Most of my music comes from Shazam. So I thought it would be cool to Shazam from one fixed place and just see the results over time. I honestly just thought it would be cool to hear what people are playing.”

If we ever needed quantifiable evidence of Mission residents’ marriage to blasting tunes around the clock, Bop Spotter is already providing it. On the first day, Sept. 29, 34 tracks were captured between 2:02 p.m. and 9:24 p.m. On day two that number rose to 101, the first track — “Worthy” by Elevation Worship, a Christian North Carolina band — being picked up at 3:12 a.m. Despite this being the very earliest days of the project, Walz says he’s already been surprised a few times by people’s musical choices and the times they play them.

“Yesterday morning, someone played ‘Me So Horny’ at like, 9 a.m.,” he laughs. “That was pretty funny. Then at 1 o’clock this morning, I guess some guy found the box and played ‘Never Gonna Give You Up’ by the Rickroll guy, Rick Astley.”

“Ass Like That” by Eminem also showed up at 6:14 a.m., sandwiched between Dr. Dre and Kendrick Lamar. Bay Area hip-hop has been captured too, via rappers like J. Stalin, Keak da Sneak and G-Eazy. If there is a favorite genre of the Mission, however, it might just be reggaeton, with entire blocks showing up by artists like Zion & Lennox, Bad Gyal, Tony Dize, Eddie Dee, Peso Pluma and La Factoria.

Walz is hoping Bop Spotter will run for long enough to capture a true reflection of Mission tastes.

“Hopefully, this will be up for years and we can log some trends,” he says. “There’s not much that could go wrong. The solar panel that powers [the phone] is pretty stable, it’s high up so people can’t really grab it. The only thing that could maybe jeopardize it is if the phone crashes or if the WiFi I’m using goes out or changes. Or if someone decides to go and take it down.”

That, Walz says, is a possibility because of clues to the box’s location that live on Bop Spotter. Twenty second previews of street noise can be heard by hovering over each track listed on the website. Muni, street sounds and small hangouts of various groups are clearly audible — which is probably how he got Rickrolled.

“How many places could that be?” Walz asks. “I think if you’re determined enough, you could probably find it.”

If Walz sounds like he doesn’t have much of an agenda, it’s because he doesn’t. Bop Spotter isn’t the first public project he’s done purely out of a sense of curiosity and a desire for fun. He’s the kind of guy who does things just to see if he can. Which is why in 2020, he created a fake political candidate and managed to get him verified on Twitter. And why, last year, he and a couple of friends opened and ran a high-end (and completely ludicrous) steakhouse in Manhattan for one night only, after cultivating a waiting list of 900 people via Google reviews. Walz enjoys the absurd but also takes on projects that are useful to the public — like Routeshuffle, a random route generator he made for runners and cyclists.

In the end, Walz is mostly motivated in all of his endeavors by a boundless sense of curiosity.

“I’m just a normal guy who knows something about technology and likes seeing amusing things,” Walz says. “I had an idea for Bop Spotter and just wanted to see what would happen.”