| 摘要 |
PURPOSE:To make a sampling frequency equivalent to its variable frequency, and to execute a pitch control by changing a revolving speed of a drum and a feeding speed of a tape in proportion to a reproducing speed variable rate, namely, a pitch rate. CONSTITUTION:A pitch rate switching circuit 31 is operated in accordance with a pitch rate, a clock frequency is varied by a synthesizer type clock generator 30, and a rotary drum 8 and a capstan 11 are controlled by making them synchronize with a clock frequency varied by a servo-circuit 19. When reproducing an original waveform 27 recorded by a sampling frequency 48kHz, by a pitch rate 1.1, it goes to a waveform 28 which has compressed a time base by 1/1.1 times as shown in the figure. Accordingly, at the time of reproducing, it becomes equivalent to a fact that a value (48kHzX1.1) which has varied a recorded sampling frequency Fs=48kHz in accordance with the pitch rate 1.1 is selected as a reference sampling frequency.
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