My father was a competent musician, though never thought about doing it professionally. He learned some songs, including Browne’s “My Opening Farewell,” so he could show customers different aspects of a guitar’s tone. “He always really liked to show me that he could play it, which I felt very honored by, you know?” Browne said. “And that goes right along with him pulling out a guitar and saying, ‘I have to show you something. Check this out.’ And he would show you what invariably would be a phenomenal guitar.”

Check this out : the three-word portal into the Fred Walecki Experience. Check this out, and he’d hand John Entwistle his first-ever Alembic bass, a brand he would go on to use for many years with the Who. Check this out, and he’d pull out a guitar by Mark Whitebook or David Russell Young, luthiers he’d discovered in the mountains of Topanga Canyon, and whose instruments he sold to James Taylor and Gram Parsons. Glyn Johns bought a David Russell Young so he’d have a good acoustic guitar for the rock bands he worked with. (Johns showed me that guitar when I visited him at home last fall; he apologized for all the scratch marks. “Everybody’s played this,” he said. “Eric has played it; Jeff Beck’s played it; Jimmy Page has played it.”)

Guest does an imitation of my father rummaging around in his shop for the item he needs you to see. Wait, what’s this thing? he’ll say, as he unearths some treasure. My dad has been doing this for as long as I can remember. It was just over here [Dad lifts up a touring case, printed with b.d., from a Bob Dylan tour]. Maybe it’s under [peers behind a platinum record the Eagles gave him for One of These Nights]. I think it’s just [moves aside a priceless Spanish guitar by the 19th-century luthier Antonio de Torres Jurado]. Oh, here! The joy for my father is in watching other people check this out. This is why when he looks at me with pure excitement and asks me to try the soup he has made from three different types of Progresso, I accept the spoon from him.

I’ve tried to get my father to wax poetic about the music that his customers were making in the ’60s and ’70s. He was there for the birth of what is sometimes called the California Sound, a blend of country, bluegrass, folk, and rock that is utterly distinctive and nearly impossible to categorize. How to contain the Beach Boys and the Byrds, the Doors and the Mamas & the Papas, Bonnie Raitt and Joni Mitchell? Gram Parsons called his own sound Cosmic American Music, and maybe that’s a better term for the entire Los Angeles scene. The music, he said, would unite “longhairs, shorthairs, people with overalls, people with their velvet gear on.” Cosmic American Music, at least, captures the movement’s spiritual aspirations, while gesturing to the distance between its stars.