Los Angeles-based musician Gnyus, who will be in town to perform tonight at The Porch Southern Fare & Juke Joint, is presenting “Summer of Love,” a free afternoon of music for the community at the Condon Band Shell. Born Kevin A. Grace in Cambridge, Gnyus grew up in West Medford. Over the years starting at Brooks Elementary School he began to learn to play several musical instruments, beginning with the violin. Today he is a multi-instrumentalist who sifts through rock, funk and soul. He’ll be on hand to sprinkle in some acoustic numbers in between the DJ beats.