An apparatus may include a hardware processor and a storage medium. The storage medium may be coupled to the processor, and may store instructions. When executed by the processor, the instructions may cause the apparatus to receive a direction signal indicating a first direction in which a head of a user is facing with respect to a fixed direction. The instructions may also cause the apparatus to convert the first direction in which the head is facing with respect to the fixed direction into a second direction in which the head is facing with respect to a third direction, connecting the head and an object. Additionally, the instructions may cause the apparatus to generate an audio signal having characteristics such that a sound generated from the audio signal is perceived by the user as arriving from the third direction.