PURPOSE: To reduce noises in pinball halls effectively and to improve the playing circumstances.

CONSTITUTION: Speakers 9 are installed to the ceiling of island 1 constituted by plural pinball game machines 2 and interstand pinball lending machines 3 aligned in parallel. In the island 1, sensor microphones 10 are installed in such a manner as one such microphone corresponds to one speaker 9, which sensor microphones 10 convert sounds from noise sources in the island 1 into electric signals and transmit them to the antiphase sound generating circuit. The antiphase sound generating circuit works out, based upon an electric signal from a sensor microphone 10, such a controlling sound signal as brings a condition where the phase of sound from a speaker 9 at a sound attenuating point (nearby part to playing customers) and the phase of sound from a noise source covered by a sensor microphone 10 at such sound attenuating point differ with each other by 180° and transmits such controlling sound signal to the speaker 9 via the amplifier.