(CNN) Jim Seals, one half of 1970s soft-rock duo Seals and Crofts, has died at the age of 80, according to his family.
Seals, together with musical partner Darrell "Dash" Crofts, was best known for hits such as "Summer Breeze," "Diamond Girl" and "Get Closer."
Announcing his death on social media, Seals' relative Brady Seals -- himself a singer-songwriter -- wrote: "I just learned that James 'Jimmy' Seals has passed. My heart just breaks for his wife Ruby and their children. Please keep them in your prayers. What an incredible legacy he leaves behind."
The musical duo -- who met in their native Texas in their teens -- got together in the late 1960s, according to the UK's PA Media news agency. They ranked among a wave of soft-rock groups of the era, including Hall & Oates, America and Bread, as well as England Dan & John Ford Coley.
The pair split in 1980 but reunited in 1991 and then again in 2004, when they released their final album, "Traces."
Coley also took to social media to pay tribute to Seals, whose younger brother Dan was his musical partner. In a lengthy piece posted to Facebook on Tuesday, he wrote: "Jimmy Seals passed away today. I spent a large portion of my musical life with this man. We toured together, he and Dash invited us to sing on Seals and Crofts records, and we played with him for years."
Describing Seals as a "dyed in the wool musical genius," Coley added: "He belonged to a group that was one of a kind. I am very sad over this but I have some of the best memories of all of us together."
Steve Miller of the Steve Miller Band tweeted: "RIP Jim Seals So long pal, thanks for all the beautiful music. - Steve."