Abstract: A guitar is formed with a one-piece molded fiberglass body having nested oppositely facing inner and outer concavities. A sound board is bonded to one side of the body to enclose the outer concavity and a substantially smaller back is bonded to the other side of the body to enclose the smaller concavity. The inner concavity has a peripheral rim which is recessed to receive the back allowing the back and exterior of the body to be uniformly coated to give the appearance of blending together as a single piece. An optional sound transmitting post may extend between the back and a central portion of the inner concavity. The inner concavity is provided with small openings or f-holes for sound communication between the concavities and the sound board has the conventional central opening.