Keyboard instrument

摘要

In response to an operation of a key, a drive signal indicating a sound waveform corresponding to the key is supplied to an excitation unit (50) provided on a soundboard (7). The soundboard (7) is vibrated in response to a mechanical vibration generated by the excitation unit (50) and generates an actively-vibrated-soundboard sound as well as an acoustic effect generated by propagation of the vibration of the soundboard (7) to a string (5). The excitation unit (50) has a voice coil (512) excited by the drive signal. The length of the voice coil (512) is equal to or smaller than a sum of a magnetic path width (mw) of a magnetic path space (525) and a double of a maximum deflection amount (sw) of the vibration member (51) connected to the soundboard (7). By determining the length of the voice coil (512) as described above, an effective drive force for exciting the soundboard (7) can be obtained and an enhanced responsiveness in a high frequency band can be obtained.