First it was Owen Bennion’s two front teeth vs. a steel basketball pole. Then it was Matt Ungaro’s left ear vs. a moth of undetermined species.

The internationally acclaimed St. Petersburg Quartet opens the 38th summer season of the Martha’s Vineyard Chamber Music Society with performances at 8 p.m. on July 7 and 8 — Monday at the Old Whaling Church in Edgartown, Tuesday at the Chilmark Community Center.

The concert program includes Alexander Glazunov’s Three Novelettes, opus 15; the String Quartet in E-flat Major by Antonin Dvorák, and with the chamber society’s artistic director, Delores Stevens, joining the group on stage, the Piano Quintet by Dmitri Shostakovich.

The folk trio of Cindy Kallet, Ellen Epstein and Michael Cicone have emerged after a 15-year recording hiatus to release Heartwalk, a collection of original songs and folk favorites. While the three may have spent the past decade and a half on other projects, the warmth and sincerity on Heartwalk demonstrates they’ve lost none of the chemistry that earned them accolades on the New England folk circuit for their previous albums Angels in Daring (1988) and Only Human (1993).

Grace Potter is two hours into her summer tour and she’s already laughing. The woman who throws herself at a Hammond B-3 organ with a force that can only be described as feral retains her cheerful sense of rock and roll social awareness.

“Yeah, we’ve got a new vehicle,” she reports. “A sprint-er.”