Legendary guitarist JJ Cale passed away last Friday (July 26) after suffering a heart attack. He was 74.The unfortunate news were announced via official website, confirming Cale's passing at a local hospital in La Jolla, California.Known as a key figure and one of the originators of the so-called "Tulsa Sound," Cale was a highly influential figure in both blues and rock world, with he likes of Eric Clapton, Lynyrd Skynyrd, Santana, Allman Brothers Band and Johnny Cash all covering at least one of his tunes. List of such songs includes staple classic rock numbers as "Cocaine," "After Midnight" and "Call Me the Breeze.""JJ Cale was loved by fans worldwide for his completely unpretentious and beautiful music," said Mike Kappus, president of the Rosebud Agency (via CNN). "He was loved even more dearly by all those he came in contact with as the most real and down-to-earth person we all knew."Throughout his over five decades-long career, the guitarist released 14 studio efforts, winning a Grammy Award for best contemporary blues album in 2008.Clapton's covers unarguably brought him the most fame, with even Cale himself once saying that he'd "probably be selling shoes today if it wasn't for Eric." Clapton paid a tribute to late axeman via official Facebook page, posting "We've lost a great artist and a great person."Another music giant left us this year. Rest in peace Mr. Cale.