| 摘要 |
PURPOSE:To make possible varying a distortion factor of an electronic music instrument using a vacuum tube during playing, while to make it easy to handle. CONSTITUTION:In order to generate timbre intentionally distorted by a vacuum tube amplifier circuit 40, a first VCA/IC 41 which controls a distortion factor by increasing and decreasing a level of music sound applied to the vacuum tube amplifier circuit 40 and a second VCA/IC 42 which controls a level of music sound to be outputted from a device output terminal are respectively arranged at a front stage and a rear stage of the vacuum tube amplifier circuit 40. A CPU 51 increasing and decreasing DC voltage is connected to the VCA/IC 41, 42 via a D/A converter 52 to decide amplification factor by the first and the second VCA/IC 41, 42. |
