| 摘要 |
PURPOSE:To obtain an excellent characteristic with simple constitution by connecting two stages of integration devices each having an adder at its output in cascade and using an output of the adder of the post stage to apply respectively feedback relating to the titled variable circuit suitable for audio tone control or the like. CONSTITUTION:A signal from an input terminal 1 and a signal extracted at an output terminal 2 are fed to an adder 6 and the summing signal is fed to an adder 41 through a gain control amplifier 7 having a gain of K. The transfer function of the circuits is expressed in anquation I . An equation II is obtained with K=(m/2)+K, the level at omega=omega0 is expressed in an equation III and an excellent control in matching to the listening and visual characteristic is attained by changing (k) linearly. When the (k) is changed positively and negatively, the boost or cut level is changed in logarithmic symmetry with respect to the (k) and very excellent change in terms of listening and viewing is attained. Then the Q of the filter is expressed as Q=1/(m/2-K) and the Q is increased as the (k) is increased. Thus, the listening and viewing characteristic is improved further. |
