Paul Curcio, the producer and studio founder best known as the producer of Metallica’s historic debut album Kill ‘Em All, died of heart failure in St. Petersburg, Florida on the night of Sept. 10, as confirmed by his daughter Brianne Curcio-Smith. He was 74.

Curcio, a native of Rochester, New York, scored hits early in his career as the guitarist of the Mojo Men with the psychedelic folk-rock quartet’s 1966 single “Dance With Me,” produced by Sylvester Stewart (a.k.a. Sly Stone), and their 1967 cover of Buffalo Springfield’s “Sit Down, I Think I Love You,” produced by Van Dyke Parks. Curcio co-founded the group in Miami with his cousin, the late Jim Alaimo (brother of the late Steve Alaimo, a regular on the Dick Clark vehicle Where the Action Is). The Mojo Men relocated to San Francisco in 1964 and signed with Autumn Records under the production hand of Stewart, then an in-house producer at the label. The band even backed Stewart under the moniker Sly and the Mojo Men, but the fruits of those efforts didn’t surface until 1995.

In 1968, Curcio founded Pacific Recording in San Mateo, the third recording studio in the U.S. (and the first in the Bay Area) to be outfitted with a 16-track tape machine. A testing ground for the gear manufacturer Ampex, the studio’s 16-track machine made Pacific a popular attraction for artists like Santana, Janis Joplin, Jimi Hendrix, and the Grateful Dead, all of whom were drawn by multi-track capabilities that were far more advanced that what was widely available at the time.

In their first self-produced effort, the Grateful Dead recorded their classic album Aoxomoxoa there, while Santana recorded their self-titled debut in the space later the same year. The following year, an embryonic pre-Patrick Simmons lineup of the Doobie Brothers recorded the demos that would lead to their signing with Warner Bros. and their association with producer Ted Templeman. (According to Curcio, Simmons joined the group midway through the recording of those demos.)

In her 2006 book If These Halls Could Talk: A Historical Tour Through San Francisco Recording Studios, author Heather Johnson provides context for why the studio was so important to artists of the time: “For late 1960s-era bands with horn and percussion ensembles, multiple guitars, and complex, multi-layered instrumentation, extra tracks were almost a necessity. The music was there, but the technology to support it wasn’t.”

In the late '70s, Curcio moved to Rochester and founded his Music America studio. In 1983, he was approached by then-Metallica manager and Megaforce Records founder Jon “Jonny Z” Zazula about recording the band’s debut album. The circumstances behind the making of Kill ‘Em All have been extensively documented, but the album -- officially certified triple-Platinum by the RIAA 1999 -- is widely regarded as the catalyst for the thrash metal movement of the ‘80s, which also included Metallica peers like Slayer, Megadeth, Exodus, and Anthrax.

In an interview conducted with Billboard earlier this year, Curcio recalled that Zazula chose him, basically, because Curcio was willing to book the session at an inexpensive rate. To the best of his memory, the project was budgeted at a lump-sum total of $15,000 for about 17 days’ worth of work. Of course, no one involved had any inkling that they were about to make history, but looking back Curcio said he was quite proud of the album and of Metallica’s success. “We were all part of making one of the greatest albums of all time,” he recalled.

Curcio continued working on titles for Zazula, including the 1984 Blue Cheer reunion album The Beast Is Back. He relocated Music America to Nashville but closed the studio down in the mid-’90s. He subsequently moved to the Tampa-St. Petersburg area, where he managed The Family Stone Experience and remained active in scouting and developing talent into the 2010s. Brianne Curcio-Smith says she knows her father “had some other things in the works” at the time of his death. “Music was in his blood,” she adds. “He would never give it up.”

Gear dealer and studio founder Dan Alexander, a professional associate of Curcio's who also once played guitar with John Lee Hooker and the Eddie Money-fronted group the Rockets, tells Billboard that he producer was "a Bay Area original, and a pioneer in the studio business. He was a character, and he will be remembered."

Curcio is survived by his four children, his sister, two nieces, and a granddaughter. A celebration of life on Lake Seminole is planned for Saturday (Sept. 29). Fittingly enough, customized guitar picks inscribed with his name and birth/death date will be handed out as keepsakes.