| 摘要 |
PURPOSE:To provide a noise elimination circuit capable of automatically eliminating a set noise such as a tone (Sharh), etc., remaining when sound volume is stopped or a residual noise, or noises that exist among plural pieces of music recorded on a cassette magnetic tape, etc. CONSTITUTION:Plural switching circuits 22 with different voltages are arranged in parallel on a switching means 23 so as to apply the voltage generated conforming to the level of an audio signal by a voltage generation circuit 21, and a cutoff frequency can be varied corresponding to the size of the level of the audio signal by a cutoff control circuit 30 comprised of capacitors C1, C2,..., Cn connected in series to the switching circuits 22, and grounded by a switching operation, and a resistor R connected commonly to the capacitors C1, C2,..., Cn. |
