Founding Allman Brothers Band drummer Butch Trucks passed away last night in West Palm Beach, FL. He was 69. A cause of death is currently unknown.

Born Claude Hudson Trucks—the nephew of Major League Baseball pitcher and coach “Fire” Virgil Trucks—the drummer has been a cornerstone of the improvisational music community for over 50 years. Trucks grew up in Jacksonville, FL and first made his name playing in the area bands The Vikings and The 31st of February, the latter of which included future Cowboy principal Scott Boyer. Duane and Gregg Allman saw The 31st of February and invited Trucks to sit in with one of their early projects, The Allman Joys. Along with the Allmans, guitarist Dickey Betts, bassist Berry Oakley and drummer Jai Johanny “Jaimoe” Johanson, Trucks co-founded The Allman Brothers Band in 1969. The group quickly emerged as one of the architects of improvisational-rock music and inspired a generation of blues and country-based Southern-rock groups. Trucks and Jaimoe helped popularize the double-drummer format, with Trucks holding the beat and Jaimoe providing the jazzy flourishes. Trucks’ work is spotlighted on all the Brothers’ albums, including generational classics like At Fillmore East and Eat a Peach as well as the commercial crossover Brothers & Sisters.

With the exception of Gregg Allman, Trucks was the group’s only constant member until their disbandment in 2014. During one of the Allmans Brothers’ breaks in the 1980s, Trucks formed the short-lived ABB spinoff BHLT with Dickey Betts, Jimmy Hall, Chuck Leavell, David Goldflies and Dan Parks. He participated in the ensemble’s 1986 reunion and remained one of the group’s core members when they reunited in 1989. In the 1990s, he helped introduced the music world to his nephew, guitar protege Derek Trucks, who started sitting in with the Brothers when he was still a preteen and officially joined the group in 1999. Trucks also expanded the Allman Brothers’ percussion section to a trio with the addition of Marc Quinones in 1991; the drummer famously plucked him out of the jazz-fusion outfit Spyro Gyra after attending a gig.

Trucks emerged as a champion for the burgeoning jamband scene in the late ’90s, regularly attending shows and festivals that spotlighted emerging bands. He formed the supergroup Frogwings—which included, Quinones, Derek Trucks, Oteil Burbridge, Jimmy Herring, Kofi Burbridge and alternately Edwin McCain and John Popper—and ran the jam-friendly Flying Frog Record label, which signed The Slip, Frogwings and Schleigho. An entrepreneur, he also founded the streaming site Moogis and launched the Roots Rock Revival instructional summer camp in Upstate New York. He also participated in the tour that helped launch this website and received the Lifetime Achievement Award at the 2012 Grammys along with the rest of his band.

Especially after the Allman Brothers split with Dickey Betts in 2000, Trucks grew into one of the legendary band’s most visible offstage spokesmen and helped lead the band until their final performance in October of 2014. He was instrumental in keeping the band visible and developing their legacy as they slowed down on the road by launching the ABB family summits Wanee and Peach Fest. After the Allman Brothers retired, he continued to play with various projects including his Freight Train Band, which featured his son Vaylor on guitar. The new band’s moniker was taken from one of Trucks’ nicknames. Trucks also led the Les Brers project, featuring numerous ABB alumni and put together various Allman-related super jams at festivals like Wanee. During his later years, he divided his time between Florida and France.

Trucks is survived by his artist wife Melinda Trucks, four children and four grandchildren. The drummer is also musically survived by nephews Derek and Duane Trucks, the latter of whom plays Widespread Panic & Hard Working Americans.

Donations and remembrances in Butch’s name may be made to The Big House Museum in Macon, Georgia.