Cancellation apparatus

A cancellation device that cancels noise coming to a region in a vicinity of a loudspeaker,

• the cancellation device comprising loudspeakers and one reference microphone,
• wherein the cancellation device at least in part is distinct from a speaker box,
• the loudspeakers are arranged on a same plane,
• the loudspeakers emit cancellation sound that cancels the noise in synchrony,
• the plane comprises a boundary between a sound emission direction of the loudspeakers and a direction opposite to the sound emission direction,
• the reference microphone is in a region that is in an opposite direction to a region where the noise is desired to be canceled,
• a ¼ wavelength of the noise to be canceled is longer than respective distances of a first distance and a second distance,
• the first distance is between the plane on which the loudspeakers are arranged and the reference microphone, and
• the second distance is between the plane on which the loudspeakers are arranged and an error microphone for confirming an effect of cancellation.