Since the curvature of a plane part 82b is smaller than that of a curved surface part 82a, it is possible for the distance between a coil 100 and the detected part 82 (plane part 82b) to be short in the aftertouch performance region than the case where the detected part 82 is one arc shape centered on a rotation shaft 90. Accordingly, the dynamic range can expand (with a significantly decrease in the sensor output value in the aftertouch performance region) without enlarging the displacement member 8 (coil 100). Accordingly, aftertouch can be accurately detected while the displacement member 8 can be miniaturized.

Since a white key 2a and a holder 9 to which the displacement member 8 is pivotally supported are assembled to the same chassis 4, the relative positional accuracy between the white key 2a and the displacement member 8 can be improved. As a result, the guide pin 73 of the linkage member 7 and the groove 80 of the displacement member 8 can be accurately engaged at the position as designed. Therefore, the initial position (angle) of the displacement member 8 before key-pressing and the displacement amount (rotation amount) of the displacement member 8 accompanying key-pressing are more likely to follow the design value. Consequently, the key-pressing information of the white key 2a can be detected with high accuracy.

A device includes a sensor circuit configured for installation in a stringed instrument such that the sensor circuit is electrically distinct from a pickup circuit of the stringed instrument, the pickup circuit including a pickup disposed proximate a string of the stringed instrument and configured to produce an audio signal of the stringed instrument in response to a movement of the string, and the string, the sensor circuit including a capacitive sensor and a sensor processing circuit in electronic communication with the capacitive sensor configured to produce a data signal based on a state of the capacitive sensor.

Provided is an audio device including: a detector configured to detect a rotational angle of a rotary operation element; a determination unit configured to determine, based on the rotational angle, whether a rotation direction of the rotary operation element is reversed; and an effect playback controller configured to play back an effect sound associated with an angle difference between the rotational angle based on when the rotation direction is reversed and a reference angle.

Provided is an audio device including: a detector configured to detect a rotational angle of a rotary operation element; a determination unit configured to determine, based on the rotational angle, whether a rotation direction of the rotary operation element is reversed; and an effect playback controller configured to play back an effect sound associated with an angle difference between the rotational angle based on when the rotation direction is reversed and a reference angle.

An electronic hi-hat 1 has a rod movable up and down with an operation of a player. A top cymbal 2 has a striking surface that can be struck by the player. A bottom cymbal 3 comes into contact with or separates from the top cymbal 2. An optical sensor 7 detects separation dimension between the top cymbal 2 and the bottom cymbal 3. The optical sensor 7 detects separation dimensions of a plurality of areas that are displaced with inclinations of the top cymbal 2 and the bottom cymbal 3 with respect to the rod r. The plurality of areas where the separation dimensions are detected are located on a common circumference of the top cymbal 2 and the bottom cymbal 3 around the rod r as a center.