It's hard to conceive a better musical foil for Steven Tyler than his longtime partner and occasional adversary. For more than 40 years, Joe Perry's monstrous, blues-on-steroids riffs have been Aerosmith's bedrock. And his solos, jutting out from "Walk This Way" or slashing boldly through the high-gloss production of later hits like "Janie's Got a Gun" and "Cryin'," have a caffeinated energy that's every bit Tyler's match. "He had a streamlined style that reminded me of Keith Richards," said Slash. "And a careless style that's really cool."

Key Tracks: "Dream On," "Walk This Way," "Janie's Got a Gun"

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