From college dorm rooms to high school sleepovers, an all-but-extinct music medium has been showing up lately. And we don’t mean CDs. Vinyl records, especially the full-length LPs that helped define the golden era of rock in the 1960s and ’70s, are suddenly cool again. Some of the new fans are baby boomers nostalgic for their youth. But to the surprise and delight of music executives, increasing numbers of the iPod generation are also purchasing turntables
