The Varitone circuit is a notch filter that utilizes a variety of capacitors to achieve a reduction in frequencies at set points within the overall bandwidth. As the varitone is rotated from Position 1 to Position 6 the center frequency(f0)of the filter shifts from higher to lower frequencies. Figure 1 demonstrates in general the type of frequency response that is created by the varitone.
*The specific characteristics are:
Position 1: Bypass (no effect)
Position 2: -5dB at 1875 Hz
Position 3: -6dB at 1090 Hz
Position 4: -7dB at 650 Hz
Position 5: -10dB at 350 Hz
Position 6: -14dB at 130 Hz
cf.
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