Angelo and Les, hip and hypnotic.

“Some guy jumped from the top balcony onto the speakers and then down onto the floor. And then some other guy dove off the stage onto his face on the floor and had to go out to our merch table. They gave him a T-shirt to wipe the blood off his face, and he ended up right back under the pit. It was crazy.” Les Claypool is speaking of an early ‘90s Primus show at the infamous south-of-the-border venue Iguanas — where they also played with tonight’s hand-picked opener Fishbone, whom Claypool describes as “heroes of ours.”

No millennials are jumping off balconies at Observatory North Park tonight, where Colonel Les Claypool’s Fearless Flying Frog Brigade is playing. But it’s still fun: a collection of music nerds of all ages and genders show up in garb depicting everything from extreme death metal to prog obscurities like Haken, peppered with acts like Zappa and King Crimson. The Crimson references will make their way from crowd to stage when the band opens with a cover of Crimson’s “Thela Hun Ginjeet (Part One),” a 1981 song that Claypool counts among his favorite tracks. There’s even a couple in the crowd dressed in frog outfits; they tell me they will get their wings and become flying frogs soon.

Frogs having fun while they wait to fly.

Fishbone frontman Angelo Moore sets up at the band’s merch booth, chatting with fans after a set that sounded tough to follow. His kindness and availability are the antithesis of the meet-and-greet packages that have become the industry norm, wherein bands charge up to two grand for a brief photo op and pre-signed swag. Neither Moore nor the fans are in any rush, and a line forms. I’ve never developed the “skill” of leaving my inner fanboy at home and conducting myself professionally, so my face hurts from smiling as I wait my turn. Watching Angelo interact with the fans in such a gentle and accommodating fashion is such a pleasure. Speaking of smiles: when my turn comes up, Moore recognizes Mr. Sardonicus on my shirt, and we chat about that film in particular and monsters in general. He points out new music and other merch for sale, including a comic he created. In the past, I would have happily shelled out cash to the merch booth because it supported the bands directly. But I know that now, promoters take up to 30 percent of merch sales, which creates a conflict for me. Before snapping the inevitable selfie, I tell Moore I have to think about it, but that I will probably get it online.

When I chat with Les Claypool, I learn that his memories of San Diego are limited to local sailing being “kinda cool,” so I spend a chunk of our time being a bass nerd. It’s one thing to hear an artist parrot lines about loving music and playing for themselves. It’s quite another thing to witness it genuinely and firsthand, as when Claypool expresses shock upon learning that he inspired Geddy Lee of Rush, one of his influences.

After he hits the stage, I start hearing snatches of conversation around me. A common refrain: “When are they going to play Animals?” The Pink Floyd album is not the most accessible release, and its complete performance by Claypool and company came about when Claypool decided that, if he ever picked up a keyboard player, the band would do that Floyd album track-by-track. That the keyboardist for this tour is Harry Waters — son of Floyd co-founder Roger Waters, the primary architect of Animals — is monumental. Hearing him sing his father’s words is as uplifting as hearing the entire audience sing along with him.

I try to get a look at how Claypool delivers the bass lines, but he turns his back to us at key moments. I’m sure he’s communicating with the drummer, but I personalize it and call him a fucker in my mind anyway. Remarkably, for all the skill and legacy onstage, it’s Beatle-spawn Sean Ono Lennon on guitar who commands my attention the most. The mild trepidation I feel at hearing someone besides David Gilmour playing Pink Floyd music evaporates when the lead break for “Dogs” comes in. It’s not so much that Lennon nails it, it’s the way he means it, and his presence onstage commands attention.

Fellow Reader scribe Gabe Garcia materializes near me, and we share a few shorthand words, watching Angelo Moore from Fishbone join the group on electronic theremin and vocals. It’s a hypnotic near-finale that leaves me feeling like I’ve seen parts of the musical universe anew, and am wiser because of it.