Tony Booth, celebrating 50 years behind the mic this year, commands the afternoon slot on Big Oldies 107.3, pumping out everything from the Shangri-Las to Sade. He’s also been moonlighting lately as a music professor. Since this is the dude who loves to tell you the stories behind the songs (were you aware that the Moody Blues’ “Nights in White Satin” was a flop upon first release?), it makes perfect sense. He’s slated to give a free lecture on the early days of rock ’n’ roll — and he was there, after all — at the University of Richmond on June 5. Sometimes the oldies just sound old. But this seasoned jock makes those vintage hits sound as fresh as a newly minted piece of vinyl. Speaking of which, don’t forget to tune in at 3:45 every afternoon for Tony’s “Forgotten 45.”