A stringed musical instrument is provided with a plate or soundboard that is curved to define a crest parallel to the strings. If the instrument is a closedbox instrument, another plate opposing the first plate may be curved to define a crest perpendicular to the strings. The first plate may be supported by transverse braces, which are scalloped to leave substantial air gaps along the glue line once the brace is attached. The back plate may be supported by a substantial longitudinal brace or spine, which runs down its center parallel to the strings. The spine contains a substantial portion of the mass of the back plate. These musical instruments have reduced wolf tones and improved harmonic generation over common instruments, and therefore have a more complex and pleasing tone than common instruments. The harmonic character of these instruments is fully exploited by using one or more harmonic bridges in addition to the primary bridge.