The present invention is a hollow body stringed musical instrument that utilizes a low mass, soundboard having a 12 to 25 foot radius dome configuration. The soundboard is made of a three ply torsion box design utilizing a honeycomb stiffening layer as the central core. Linear adjustable tuning braces are incorporated in the hollow body. The side and back of the instrument are also of a three ply construction having a polymer ir inorganic foam as the central layer. (Preferably this will be a closed cell foam.) The back also has a domed configuration with a 12 to 15 foot radius. All structural braces are eliminated from the interior of the instrument's body.