A pressing surface of a hammer and a to-be-pressed surface of a key switch have relatively-concaved shapes in a longitudinal direction of the hammer. When a switch body is pressed by the hammer, an inclination caused by an overall curvature of the switch body that results from the fact that the switch body is pressed by the hammer from an oblique direction is canceled by an inclination of the switch body caused by partial compression and deformation that results from the relatively-concaved shapes, so that movable contacts in the switch body frontally face stationary contacts and come into contact with the stationary contacts, respectively.

A keyboard device includes: a frame; a plurality of keys including a first key and a second key, the plurality of keys rotating around the frame; and a plurality of guides for restricting an operation of each of the plurality of keys, at positions different in a vertical direction, each of the plurality of guides including a first member that is softer than the frame and the plurality of keys, and a second member that is harder than the first member, wherein each of the plurality of guides is in a first state where a corresponding one of the keys comes into contact with the first member, or in a second state where the corresponding one of the keys comes into contact with the second member.

A sound signal generation device comprises a first signal generation instructor and a second signal generation instructor. The first signal generation instructor provides an instruction for generating a key depression sound signal corresponding to a key depression at the time of the key depression based on key operation information corresponding to an operation of each key of a keyboard. The second signal generation instructor provides an instruction for generating a key release sound signal according to a manner of a key release at the time of the key release based on the key operation information.

A signal supply device according to an embodiment of the present invention includes a generator configured to generate a first sound signal and a second sound signal in accordance with an instruction signal including operation body information corresponding to an operation input to an operation body and linked member information corresponding to a movement of a linked member linked with the operation body and an adjuster configured to adjust a relationship between the first sound signal and the second sound signal on the basis of the operation body information and the linked member information.

A sensor includes: an upper electrode; a lower electrode provided facing the upper electrode; an upper electrode support portion provided in an upper portion of the upper electrode; a deforming portion provided at both ends of the upper electrode support portion and enabling a distance between the upper electrode and the lower electrode to be changed; a rotatable actuator arranged facing the upper electrode support portion; and a member arranged between the upper electrode support portion and the actuator, and capable of moving relative to at least one of the actuator and the upper electrode support portion when the actuator presses the upper electrode support portion.

A signal processing method according to an embodiment of the present disclosure includes outputting a second sound signal by varying a level of a portion of a band of a first sound signal based on a second parameter corresponding to a displacement of each of a plurality of operators, the first sound signal being identified by a first parameter corresponding to the displacement, the second parameter being different from the first parameter.

An electronic keyboard instrument includes: a keyboard including a plurality of keys; a plurality of switches that are provided for each key and include a first switch and a second switch that are sequentially turned on by pressing of the key; and a processor. The processor instructs that a noise sound corresponding to a selected musical instrument sound be produced in accordance with a prescribed first envelope upon detecting turning on of the first switch by pressing of the key, and instructs that a main musical sound corresponding to the selected musical instrument sound be produced after detecting turning on of the second switch.

A signal supply device according to an aspect of the present invention includes a generator configured to generate a first sound signal and a second sound signal in accordance with an instruction signal corresponding to an operation input to an operation body and an adjuster configured to calculate an acceleration of the operation body in accordance with the instruction signal and to adjust a relationship between the first sound signal and the second sound signal on the basis of the acceleration.

A relationship of 0<.sub.1<2.sub.1 is satisfied, where .sub.1 is an angle formed between a first line which is vertical to a parallel line passing through a pivot center point and being parallel to a pivot extending direction, passes through a center point of a first portion from the center point of the first portion toward the parallel line, and a second line which is vertical, at the center point of the first portion, to a first portion extending direction, passes through the center point of the first portion toward a vertical line being vertical to the parallel line and passing through the pivot center point, and where .sub.1 is an angle formed between the first line and a third line connecting the pivot center point and the center point of the first portion from the center point of the first portion toward the pivot center point.

A keyboard apparatus includes a key, a frame arranged below the key, a key-side supporting section connected to a member a positional relationship of which is fixed to the key and extending more downward than the member, and a flexible section supported by the key-side supporting section, having flexibility in at least an up-and-down direction, and configured to rotate the key with respect to the frame.