| 摘要 |
PURPOSE:To realize the generation of a mute effect by providing an amplitude detecting means and a mute realizing means and stopping quickly the generation of a musical sound, when the attenuation degree of amplitude of an ultrasonic wave is a prescribed value or above. CONSTITUTION:A performer executes a musical performance, while designating a sound pitch by pressing a string 3 against a sound pitch designating part 1. A position discriminating means 4 gives an ultrasonic wave to the string 3 and counts its propagation time, and discriminates the position of the designating part 1. The ultrasonic wave propagated through the string 3 is supplied in parallel to an amplitude detecting means, as well, therefore, the means 6 detects continuously its amplitude, and a mute realizing means 7 calculates the attenuation degree of the amplitude, based on the amplitude supplied successively from the means 6. Subsequently, when the position of the designating part 1 and the attenuation degree of the amplitude are calculated, a musical sound generating means 5 starts to sound the musical sound of a sound pitch corresponding to its position. In this case, the means decides whether the attenuation degree is more than a prescribed value or not, and when it is under said value, the operation of the means 5 is permitted, and when it is the prescribed value, or above the means 5 is allowed to end quickly the generation of a musical sound and a muting effect is realized. |
