Hi, i am wondering what causes "outer-groove distortion" or more simplified - i have two original Rolling Stone's records. No2, and that first one, just named Rolling Stones. On the Rolling Stones, listening to Route 66, is a bit of an ear-pain inducer, whereas Jaggers's S'es are sharp and hars, more pointed to the rigth side of "rightside" of the mono track. Its not raspy, but he's vocals are harsh on that song. And that goes for No2 also, he's sses are sharp and harsh. On Route 66, the sixty-six sounds is sharp and harsh, but not SHHixty shhix But, it mellows down close to the center of the record. Is this just because its from 1964, and the limitations of that decade's recording equipment?