A tone generator unit of a tone plate percussion instrument, comprising:
- a plurality of tone plates each adapted to vibrate to generate a musical tone of a specific tone pitch when struck;
- and
- a resonance box having a plurality of resonance chambers corresponding to respective ones of said plurality of tone plates and each having an opening side thereof,
- wherein said plurality of tone plates are mounted to said resonance box so as to be capable of vibrating, with each of the tone plates located close to the opening side of a corresponding one of the resonance chambers, whereby said resonance box and said plurality of tone plates are formed into one unit.