An improved resonator for keyboard percussion instruments such as marimba, vibraphone and xylophone and instruments including such resonators are described herein. In one or more embodiments, a tubular resonator bent or formed into a smooth curve, open or stopped on one end, resonating only its natural fundamental frequency and its natural overtones with no non-harmonic resonances from a struck tone bar associated with the resonator is provided. According to one or more embodiments, the number of joints in the resonator is reduced to less than two joints.