Thurl Ravenscroft, who roared “They’re Grrrrreeeat!” in Kellogg’s Tony the Tiger ads and voiced a host of Disney characters, died Sunday of prostate cancer. He was 91.For more than 50 years, Ravenscroft was the voice behind Tony the Tiger, TV’s popular cartoon pitchman for Kellogg’s Frosted Flakes. He is also well known for his cartoon voice work with Disney and Chuck Jones – including singing the classic “You’re a Mean One, Mr. Grinch” – and lent his voice to characters on rides at Disneyland, including the Pirates of the Caribbean, Splash Mountain, the Enchanted Tiki Room and the Haunted Mansion. Born in Norfolk, Neb., Ravenscroft moved to California in 1933 to study art. By the mid-1930s he was appearing regularly on radio, and by the late-1930s he was singing backup for Bing Crosby. In 1952, Ravenscroft’s voice appeared in the first Frosted Flakes commercial.