Abstract: Disclosed is a string musical instrument suitable for use as a guitar having a hollow base with outer and inner ends, the instrument neck extending from the base inner end. The base defines the instrument sound box; is disclosed having front and back surfaces members interconnected along their outer edges by a side wall, the front surface member being formed as a planar member which functions as a sound board; and is shaped to define inner and outer end portions of, respectively, greater and smaller widths interconnected by a narrowing middle portion, thereby the base's smaller outer end portion adapts to a person's body to facilitate the holding and playing of same. The base further is disclosed with sound hole or holes formed in its inner end portion at the widest portion thereof to increase the region in the guitar base for concentrically generating sound and enhance its sound generating characteristics.