A sound reverberator device for detachable connection to the strings of a string musical instrument which has strings tensioned over a bridge piece connected to the top wall of the sound box or the instrument. The reverberator comprises three spaced apart metal coil springs secured side-by-side at a common end to a spring support. A metallic string attachment member is secured to a free end of each of the springs. The attachment member has string engaging fingers for engaging a respective one of a pair of adjacent strings of the musical instrument. The attachment member further has a bridge abutment portion for contact with the bridge piece. When the reverberator is connected to the musical instrument, the springs are tensioned with the attachment member connected to the strings whereby vibrations imparted to the strings will be transmitted to the bridge piece and the associated spring. The spring will then vibrate and transmit its vibrations to the sound box through the bridge piece whereby to modify the tonality sound generated by the sound box. A sound damping device also provides progressive sound damping produced by the springs.