If you’re going to put together an unplugged show, it’s always more intriguing when the participating bands typically rely on extreme volume. After all, who would you be more fascinated to see without amplification: Black Sabbath or Bread? The Melvins or Jewel? That should explain the impetus behind Mike Chapa’s counterintuitive but compelling “SA Unplugged” night at Limelight (2718 N. St. Mary’s) on Saturday, June 6. Chapa has enlisted the Masters of Love, Chris Gavito, the Black Friday, mega-talented former Big Soy singer-guitarist John Edds, Snowbyrd, and headliner Marcus Rubio (with his Gospel Choir of Pillows, featuring Current art director Chuck Kerr on drums). For many of these acts, the gap between their customary volume and what they’ll be delivering at Limelight will probably be jarring, but that’s why this is a show that shouldn’t be missed. Hopefully, the gig will also offer uncooked tastes of Rubio’s forthcoming aquatic concept album Oceanic Tremors, and Snowbyrd’s in-the-works Diosdado, the band’s final collection of recordings with drummer Manny Castillo, who passed away in January. The music starts at 10 p.m., with a $5 cover.