| 摘要 |
PROBLEM TO BE SOLVED: To enable even a beginner to easily perform string rubbing operation, obtain the same feeling with string rubbing operation on a rubbed string instru ment which actually has strings, and simplify a string rubbing operation detecting mechanism and make the characteristics of a product uniform. SOLUTION: A main body 1 is provided with plural strings 11 and an optical sensor 12 in simple structure composed of a transmission type photointerrupter is set nearby the strings 11. A bow part 13 which is rubbed against the strings 11 have plural holes which are irradiated with a light beam and transmit the light beam when rubbed against the strings. In the string rubbing operation, the light beam impinges on the holes and other parts and is transmitted and cut off, so that pulses having cycles corresponding to the string rubbing speed are inputted in the form of a digital signal from the optical sensor 12 to a microcomputer in the main body 1 not through an A/D converter. The microcomputer calculates the cycles of the pulses and controls the sound volume of a musical sound to be generated without any variance. |
