Patent ID: 11922912
Assignee: YAMAHA CORPORATION
Field: Other consumer goods (Other fields)
Classification: CPC G  H | IPC G

Claim 0:
1. An instrument playing apparatus comprising:
a movable member configured to be displaced responsive to a playing operation of a user;
a detection part formed from a magnetic or conductive body and disposed on the movable member; and
a filter that includes a coil and is configured to generate a detection signal from a reference signal, the filter having a frequency response that changes depending on a distance between the detection part and the coil,
wherein:
the filter is a low pass filter that includes:
an input to which the reference signal is supplied;
an output that outputs the detection signal;
the coil including a first coil disposed between the input and a coupling point and a second coil disposed between the coupling point and the output;
a first capacitive element wired to the coupling point not via the first coil or the second coil; and
a second capacitive element wired to the output, and

directions of currents flowing through the first coil and the second coil are opposite in sense.