| 摘要 |
PURPOSE:To change the feeling of stereo and spread of reproduced sound arbitrarily and continuously, by changing the cut-off frequency of a filter circuit through the use of a variable resistor for the sound image control of a TV set equipped with two speakers. CONSTITUTION:Left and right channel outputs 1L, 1R of a demodulation circuit 1 of a television set are inputted to LPF circuits 10L, 10R directly or via delay circuits 2L, 2R respectively. A transistor Q13 and a variable resistor 5 are commonly used for the circuits 10L, 10R. With the constitution like this, when the resistor R5 is decreased, the cut-off frequency of the circuits 10L, 10R is increased, e.g., more than audible band. Thus, an output almost close to monaural reproduction can be obtained for speakers 6L, 6R. When the resistor R5 is increased, the said cut-off frequency is within the audible range. Thus, the playback sound having an arbitrary stereo or spread of feeling can be obtained from the speakers 6L, 6R, by adjusting the resistor R5. |
