Reduction of heavy-weight impact noise was made by the active control of ceiling vibration. Experiment was carried out with a small concrete box (internal dimension: 80×80×80cm) with plywood floor and hardboard ceiling. The vibration acceleration level of the ceiling was decreased by 10 dB and the floor impact noise level by 6 dB by the control system. Furthermore, the floor impact noise level by footstep was decreased by 4 dB.
