About 10 years ago on Thanksgiving, my grandpa waited until everyone had their mouths full, as he did when he really wanted our attention, then he shared a dream he’d recently had about how he was Santa Claus. In the dream, he was surrounded by adoring elves. Pretty cute, huh? Except they weren’t elves — they were strippers peeling off their skimpy green outfits and jockeying to, ahem, take a ride on Santa’s bowl full of jelly. Naturally, my mom and aunt were appalled. And, naturally, I had to bite my lower lip hard to keep from blasting my stuffing across the table. Man, I miss him. I hadn’t thought of that story for a long time before hearing Lee “Scratch†Perry’s “Pum Pum,†the dancefloor anthem from Perry’s ambitious new album, produced by his pal Andrew W.K. Most people know Perry as a legendary Jamaican musician and producer who helped create both the signature waka-waka sound of reggae and the signature stoned production quality of dub, among other influential moves. He is a giant among giants despite his diminutive stature — truly a living legend. He’s also a dirty old man. I can’t sincerely say that “Pum Pum†is one of my favorite tracks right now just like I can’t say that this Spring-Winter pairing of W.K. and Perry is the same as Rick Rubin and Johnny Cash, but I can say that it’s pretty fascinating. The crazy old bastard in the multicolored hat manages to mix reggaeton-style beats and synths with pornstar moans, lots of dirty-talk and, inexplicably, Jesus. Or that’s what I think he does. Truthfully, I can only understand about half of what is going on at any given time in “Pum Pum,†but I’m pretty sure it’s naughty. That’s part of the allure. Some are calling Perry’s new album a return to form. That may be so, but to me it sounds more like a lovingly perverse old coot flipping the bird at all of us and speaking what’s on the unfiltered side of his mind. Grandpa would be proud.