Audio system

An audio system for a room comprising:

• a sound source;
• a first speaker for emitting a first sound including a reflected composite signal based on an audio signal from the sound source;
• a second speaker for emitting a second sound;
• a microphone disposed at a listening position between the first and second speakers for picking up the first sound from the first speaker and the second sound from the second speaker;
• control means for obtaining a time difference and a sound pressure difference between the reflected composite signal and the second sound picked up by the microphone based on characteristic information of the first and second sounds;
• phase adjusting means for inverting the phase of the audio signal from the sound source for producing an antiphase audio signal;
• filter means for extracting an input audio signal of a predetermined frequency band from the antiphase audio signal, in which the predetermined frequency band corresponds to a frequency band of the reflected composite signal included in the first sound picked up by the microphone;
• delay means for delaying the antiphase audio signal based on the time difference so that the second sound coincides with the first sound at the microphone;
• amplitude adjusting means for adjusting the amplitude of the antiphase audio signal so as to reduce the second pressure difference;
• applying means for applying the inverted antiphase audio signal to the second speaker for emitting the second sound.