If you remember Jimmy Carter as President, you may be too old to appreciate the latest musical sensation from the Hawkeye State. Davenport native Bix Biederbecke may’ve been the first Iowan to win national acclaim for his Dixieland jazz in the 1920s and ’30s. A decade later, it was Glenn Miller of Clarinda — and later “76 Trombones” led “The Music Man” and Mason City’s Meredith Willson to fame. Today’s music from Iowa has a slightly different flavor, thrash metal, characterized by pounding guitars and screamed, often obscene, lyrics. The band Slipknot is comprised of nine guys who always wear masks — and they’re from Des Moines. Their album called “Iowa” debuted this week at number-three on American charts and is number-one in Great Britain and Canada. More than 255-thousand copies of “Iowa” sold in the past week. It’s the first time an Iowa act has won national recognition since Dee Jay and the Runaways from Spirit Lake hit the pop charts in the 1960s with “Peter Rabbit.”