Used musical instruments: Rockin Bob's Guitars
Location: 31 Holland St., Somerville
Hours: Mon.-Thurs. 11 a.m. to 6 p.m.; Fri. 11 a.m. to 7 p.m.; Sat. 11 a.m. to 5 p.m.; Closed on Sundays
Phone Number: 617-625-7707

Rockin Bob's, which was formerly known as Used Sound, is in the heart of Davis Square and sells, repairs, and restores new and used guitars, amplifiers, stereo gear, and accessories.