His death was caused by complications related to lymphoma, said Marty Martel, a talent agent who worked with Seals. The singer died at his daughter’s home in Nashville, the Associated Press reported.
England Dan and John Ford Coley were known for ballads with lush harmonies and acoustic-based songs. Their 1976 album "Nights Are Forever," which had a fuller sound, drew comparisons to the Eagles.
The pop-rock duo also had Top 10 hits with the late 1970s singles "Nights Are Forever Without You," "We’ll Never Have to Say Goodbye Again" and "Love Is the Answer."
Between 1985 and 1990, he had 11 songs top the country charts, including“Meet Me in Montana,” a duet he recorded with Marie Osmond. Other hits included the danceable "Bop," the rodeo story "Everything That Glitters (Is Not Gold)" and "You Still Move Me."
He came "naturally to his loose, intimate country sound, which has a Ricky Skaggs-like amiability," People magazine said in 1985.
His sound was a "judicious, commercially successful blend of honky-tonk traditionalism, mild country rock and pop slickness," Mike Boehm wrote in 1989 in The Times.
An unplanned performance by the Seals brothers at Nashville’s Grand Ole Opry in 2002 convinced them that they should make it a habit.
"We played ‘Summer Breeze’ and ‘Diamond Girl,’ " Dan later recalled, referring to two Seals & Crofts hits. "When it was over, the audience stood up and . . . just kept clapping."
"Now workin’ with my brother Jim, it’s almost like a dream," Dan said ina promotional video for their act, Seals & Seals. The brothers had recorded about eight songs, which reportedly will be released.
In interviews, Jim praised his brother’s songwriting skills and said "he’s got a great voice. He can sing anything."
Dan Wayland Seals was born Feb. 8, 1948, in McCamey, Texas. By age 4, he was standing on an apple crate to play stand-up bass in the Seals Family Band formed by his father, E.W. "Waylon" Seals, who was a pipe-fitter for Shell Oil.
When his parents split up, Seals moved around Texas with his mother before settling in Dallas in 1958.
In high school, Seals played in garage bands, where he met Coley. They performed in a band called the Shimmerers, which became known as Southwest F.O.B.
Seals and Coley had started playing acoustic country-folk music together and left the group in 1969 to perform as a duo. Their breakthrough song, "I’d Really Love to See You Tonight" was written by Parker McGee and released in 1976.
After the duo split up, Seals had financial trouble while battling the Internal Revenue Service over taxes. By 1983, he was experiencing success on the country charts.
With the arrival of Garth Brooks on the country landscape, Seals found his quieter style out of favor, according to "All Music Guide" and effectively became a touring artist in the late 1990s.
A statement on the said Dan would be "remembered for his gentle smile, easy going demeanor, his enduring faith and endless generosity."
In addition to his brother, Jim, Seals’ survivors include his wife, Andrea; four children; and seven grandchildren.