Danny Smythe, the founding drummer of '60s pop stars the Box Tops, died on Wednesday (July 6) at the age of 67. The cause of death is unknown.

The news comes from Vintage Vinyl, who note that the Memphis-based group were formed out of the ashes of the Devilles, which Smythe co-founded in 1963. But as personnel changed, with Smythe as the only original member by early 1967, so did their name.

With Alex Chilton's gruff voice front-and-center, the Box Tops made good use of their first time in a recording studio. They cut "The Letter," a less-than-two-minute perfect piece of blue-eyed soul that opens with Smythe's count-in, and took it to No. 1. in the summer of 1967. The song was also nominated for two Grammys -- Group Vocal Performance and Contemporary Vocal Group -- but lost in both categories to the 5th Dimension's Jimmy Webb-penned "Up, Up and Away." Smythe would appear on one other single by the group, a No. 24 hit called "Neon Rainbow," before leaving at the end of the year. The group had five other Top 40 hits, including a No. 2 smash with "Cry Like a Baby," before calling it quits in 1972.

According to the bio on the Box Tops' website, Smythe studied art after leaving the music industry. He painted murals in restaurants and hotel lobbies and spent decades as a freelance illustrator for advertising agencies.

The original lineup of the Box Tops -- including Chilton, who became a reticent cult hero with '70s power pop band Big Star -- reunited in 1996. They released Tear Off!, whose cover was designed by Smythe, two years later, and continued to tour until Chilton's death in 2010.

Smythe's death marks the fourth Memphis music legend to have passed within the last four weeks. Wayne Jackson of the Memphis Horns, who played on many hits for Stax Records, died on June 21. Sir Mack Rice, who recorded for Stax and wrote the soul classics "Mustang Sally" and "Respect Yourself," died on June 27. A day later, Scotty Moore, Elvis Presley's first guitar player, passed away.

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