JPH067312U - Audio input level adjuster - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a voice input level adjusting device capable of obtaining a constant output level by detecting and adjusting a level difference for each input device and a sound source. A volume adjusting means 1 for adjusting and outputting a level of an audio signal supplied from various sound sources upon receiving a control signal, and a reference for oscillating and transmitting a reference signal set within a band of the audio signal. The signal generating means 2, the sound volume comparing means 3 for comparing and detecting the levels of the audio signal and the reference signal and transmitting the comparison signal, and the detection signal for the comparison signal and transmitting the control signal to the sound volume adjusting means 1. And the control means 4.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an audio input level adjusting device for an amplifier used as an AV center for audio / visual equipment.

[0002]

[Prior art]

 Conventionally, such an audio input level adjusting device will be described with reference to FIG. FIG. 4 is a schematic block diagram showing a conventional audio input level adjusting device.

In FIG. 4, audio signals transmitted from various input devices 80 are supplied to each attenuator attenuator 90. Each attenuator attenuator 90 adjusts the level of the audio signal with the semi-fixed volume 91, and supplies this audio signal to the source switching unit 100. At this time, the source switching unit 100 selects the input device 80 from the audio signal supplied from each attenuator attenuator 90 by the operation unit 110 according to the user's preference.

Then, the source switching unit 100 supplies the audio signal to the amplification unit 120. At this time, the amplification unit 120 adjusts the level of the audio signal with the operation unit 110 according to the preference of the user and outputs the audio signal to the main amplifier (not shown).

As a result, in order to match the levels of the audio signals sent from the input devices 80, the volume 91 of the attenuator attenuator 90 can be adjusted for each input device 80 to eliminate the level difference. .

[0006]

[Problems to be solved by the device]

 However, in the above-mentioned conventional audio input level adjusting device, the work of adjusting the volume 91 of the attenuator attenuator 90 by matching the audio signal levels of the respective input devices 80 is a very troublesome work. In addition, there is a problem that the level difference caused by each sound source of each input device 80 cannot be adjusted.

The present invention has been made in view of the above problems, and an object of the present invention is to detect and adjust the level difference between each input device and each sound source to obtain a constant output level. A voice input level adjusting device is provided.

[0008]

[Means for Solving the Problems]

 In order to achieve the above object, the present invention provides volume control means for adjusting and outputting the levels of audio signals supplied from various sound sources, and a reference signal set within the band of the audio signals. A reference signal generating means for oscillating and transmitting, a volume comparing means for comparing and detecting the levels of the audio signal and the reference signal and transmitting a comparison signal, and detecting and judging the comparison signal for controlling the volume adjusting means. It is composed of control means for transmitting signals.

[0009]

[Action]

 With this configuration, the level of the audio signal supplied from the sound source is automatically made equal to the level of the reference signal and sent to the main amplifier in the next stage, so the sound source changes and the level of the input audio signal is set. Even if it is out of range, the user can enjoy the proper volume from the speaker.

[0010]

【Example】

 An audio input level adjusting device of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an outline of a voice input level adjusting device of the present invention.

In FIG. 1, a volume adjusting means 1 adjusts an input level of an audio input signal generated for each other sound source such as a CD player, an LD player or the like, which is input in response to a control signal, to adjust a main amplifier of a next stage ( (Not shown). The reference signal generating means 2 sends the reference signal set within the band of the audio signal, and the volume comparing means 3 outputs the level of the reference signal and the level of the audio signal sent from the volume adjusting means 1. And are compared and detected, and a comparison signal is transmitted. Then, the control means 4 receives the comparison signal and makes a judgment to generate a control signal and supplies it to the volume adjusting means 1.

(Embodiment 1) FIG. 2 is a block diagram showing a first embodiment of an audio input level adjusting apparatus of the present invention.

In FIG. 2, the volume adjusting means 1 is composed of an electric volume 10, an electric motor 11, and a motor drive IC 12. The reference signal generating means 2 is composed of an oscillating circuit 20 and a manual volume control 21, and the volume comparing means 3 is composed of two level comparators 30 and 31 having different determination levels. The control means 4 is composed of a volume change determination circuit 40 and a decoder 41.

Next, the operation of the first embodiment of the audio input level adjusting apparatus of the present invention configured as described above will be described.

The electric volume 10 supplies audio input signals generated from various sound sources (not shown), drives the electric motor 11 to adjust the level of the audio signal, and converts the audio signal into a conversion circuit 5 Supply to.

The conversion circuit 5 is composed of a rectification circuit 50 and an integration circuit 51, which converts the audio signal into a DC voltage and supplies it to the level comparators 30 and 31.

The oscillator circuit 20 also generates a reference signal within the band of the audio signal and supplies it to the volume control 21. The volume control 21 adjusts the level of the reference signal according to the preference of the user and supplies the reference signal to the conversion circuit 6. Then, the conversion circuit 6 converts the reference signal into a DC voltage and supplies it to the level comparators 30 and 31.

Then, the two level comparators 30 and 31 preset the upper limit level and the lower limit level of the reference signal so that the level of the audio signal is within the upper limit level and the lower limit level. Compare and detect whether or not. Then, an upper limit comparison signal is supplied from the level comparator 30 and a lower limit comparison signal is supplied from the level comparator 31 to the volume change determination circuit 40.

The volume change determination circuit 40 detects these two comparison signals and detects the UP signal for increasing the level of the audio signal, the DOWN signal for decreasing the level of the audio signal, and the current audio signal. And a holding signal for holding the level as it is as a determination signal are supplied to the decoder 41.

The decoder 41 amplifies the control signal according to these determination signals by the motor drive IC 12 and supplies the control signal to the electric motor 11.

By driving the electric motor 11 to adjust the electric volume 10, the level of the audio signal output to the main amplifier (not shown) is adjusted.

In addition, in order to detect the presence or absence of an audio signal transmitted from various sound sources and stop the operation of the audio input level adjusting device when the audio signal is not transmitted, the level comparator 70 and the signal presence / absence are detected. A judgment circuit 71, a conversion circuit 6 for transmitting the converted reference signal, and a mute circuit 72 provided between the level comparators 30 and 31 are provided.

The mute circuit 72 is composed of an FET and operates as a switch that is turned on when the voltage applied to the gate is high level and turned off when the voltage applied to the gate is low level.

The mute circuit 72 and the signal presence / absence judging circuit 71 operate the audio input level adjusting device when the level of the audio signal is below a certain level (between the songs, the beginning and the end of the song, etc.). The signal presence / absence determination circuit 71 detects the audio signal input from the sound source and supplies the determination signal to the mute circuit 72.

When the mute circuit 72 detects the determination signal that the level of the audio signal is high, the mute circuit 72 connects the conversion circuit 6 and the level comparators 30 and 31 and determines that the level is low. When the determination signal of is detected, the connection between the conversion circuit 6 and each of the level comparators 30 and 31 is released. As a result, when the audio signal from the sound source is not transmitted, the loudspeaker (not shown) can be prevented from generating a loud sound when the electric potentiometer 10 is set to the maximum position. .

Further, the level comparator 70 supplies the level of the audio signal before being supplied to the electric volume control 10 and the level of the reference signal adjusted by the volume control 21 to detect and compare the level of the comparison signal. Is supplied to the volume change determination circuit 40.

Then, the volume change judging circuit 40 performs ON / OFF operation of the operation according to the comparison signal.

In the first embodiment of the present invention configured as described above, the level of the reference signal adjusted by the volume control 21 of the reference signal sent from the oscillation circuit 20 according to the user's preference, A control signal is supplied to the electric motor 11 that drives and adjusts the electric potentiometer 10 so as to compare and detect the levels of the audio signals supplied from various sound sources and make the levels the same. The level of the audio signal and the level of the reference signal of the volume control 21 can be set to the same level according to the adjustment of the electric volume 10. That is, even if the level adjustment of the volume control 21 and the level adjustment of the electric volume 10 are automatically made the same, and the level of the input audio signal is changed due to the change of the volume, even if it is out of the set range, It can be automatically adjusted within the specified range.

Second Embodiment Hereinafter, a second embodiment of the present invention will be described with reference to FIG. The same parts as those in the first embodiment are designated by the same reference numerals.

In FIG. 3, the volume adjusting means 1 is an electronic volume 13, and the reference signal generating means 2 is composed of an oscillation circuit 20, an electronic volume 22, a volume key 23 and a decoder 24. Further, the volume comparison means 3 is composed of two level comparators 30 and 31 having different level judgments. The control means 4 is composed of a volume change determination circuit 40 and a decoder 41.

Next, the operation of the second embodiment of the audio input level adjusting device of the present invention constructed as described above will be explained.

The electronic volume 13 supplies audio signals generated from various sound sources (not shown), adjusts the level of the audio signals, and supplies the audio signals to the conversion circuit 5. Then, the conversion circuit 5 converts the audio signal into a DC voltage and supplies it to the level comparators 30 1 and 31 2.

The oscillator circuit 20 also generates a reference signal within the band of the audio signal and supplies it to the electronic volume 22. Then, the volume key 23 is adjusted according to the preference of the user to supply the level signal to the decoder 24. The decoder 24 supplies a level adjustment signal to the electronic volume 22 according to this level signal.

The electronic volume 22 adjusts the level of the reference signal according to the level adjustment signal, and supplies this reference signal to the conversion circuit 6.

The conversion circuit 6 converts the DC voltage and supplies the DC voltage to the level comparators 30 and 31, respectively.

Then, the two level comparators 30 and 31 compare and detect whether or not the level of the audio signal is within the range between the upper limit level and the lower limit level of the reference signal, and detect the comparison signal as a volume change determination circuit. Supply to 40.

Then, the sound volume change determination circuit 40 detects these two comparison signals and supplies the determination signal to the decoder 41.

The decoder 41 supplies a control signal to the electronic volume 13 in response to the determination signal, and the electronic volume 13 adjusts the level of the audio signal so that the electronic volume 13 matches the level of the reference signal in accordance with the control signal. .

In order to detect the presence or absence of an audio signal transmitted from various sound sources (not shown) and stop the operation of the audio input level adjusting device when the audio signal is not transmitted, The switch 73a between the volume 13 and the decoder 41, the interlock switch 73 including the electronic volume 22 and the switch 73b between the decoder 24, the signal presence / absence determination circuit 71, the mute circuit 72, the level comparator 70, and the timer IC 74 are converted. A container 75 and a changeover switch 76 are provided. The operation of these configurations will be described, but the description of the operation of the signal presence / absence determination circuit 71, the mute circuit 72, and the level comparator 70 has been described in the first embodiment, and will not be repeated.

First, the user operates a source selector switch (not shown) to supply a switching signal to the interlock switch 73.

The interlocking switch 73 performs an ON / OFF operation according to the switching signal, and when the ON operation is performed, both the switches 73a and 73b are turned ON, and when the OFF operation is performed, both the switches 73a and 73b are performed. Turn it off.

Further, the timer IC 74, which has set a predetermined time, supplies an OFF signal to the changeover switch 76 via the converter 75 to disconnect the connection between the level comparator 70 and the volume change determination circuit 40. By doing so, the operation of the audio input level adjusting device can be stopped. In other words, the control operation of the volume adjustment is performed only for a certain time after the sound source is changed, and after the volume adjustment, the control operation is stopped, that is, the holding state is maintained.

In the second embodiment of the audio input level adjusting device of the present invention configured as described above, the reference signal sent from the oscillation circuit 20 is supplied to the electronic volume 22 according to the user's preference. A control signal is supplied from the decoder 41 to the electronic volume 13 so that the level of the adjusted reference signal and the level of the audio signal are detected by comparison and detection. Then, according to the adjustment of the electronic volume 13, the level of the audio signal and the level of the reference signal of the electronic volume 22 can be made the same level. That is, the level adjustment of the electronic volume 22 and the level adjustment of the electronic volume 13 are automatically set to be the same, and even if the level of the input audio signal deviates from the set range due to a change in volume, the level is automatically adjusted. It can be adjusted within the predetermined range.

[0044]

[Effect of device]

 The audio input level adjusting device of the present invention configured as described above comprises a volume adjusting means for adjusting and outputting the levels of audio signals supplied from various sound sources in response to control signals, and a band of the audio signals. A reference signal generating means for oscillating and transmitting a reference signal set therein, a volume comparing means for comparing and detecting the levels of the audio signal and the reference signal and transmitting a comparison signal, and detecting and judging the comparison signal And a control means for sending a control signal to the volume adjusting means, so that the level of the audio signal supplied from the sound source is automatically made equal to the level of the reference signal and sent to the main amplifier of the next stage. Therefore, even if the sound source changes and the level of the input audio signal deviates from the set range, the user can enjoy an appropriate volume from the speaker. .

[Brief description of drawings]

FIG. 1 is a block diagram showing an outline of an audio input level adjusting device of the present invention.

FIG. 2 is a block diagram showing an outline of the first embodiment of the audio input level adjusting device of the present invention.

FIG. 3 is a block diagram showing an outline of a second embodiment of the voice input level adjusting device of the present invention.

FIG. 4 is a block diagram showing an outline of a conventional audio input level adjusting device.

[Explanation of symbols]

 1 Volume Adjusting Means 2 Reference Signal Generating Means 3 Volume Comparing Means 4 Control Means

Claims (1)

[Scope of utility model registration request] 1. A volume adjusting means for adjusting and outputting levels of audio signals supplied from various sound sources in response to a control signal, and a reference for oscillating and transmitting a reference signal set within a band of the audio signal. A signal generating means, a volume comparing means for comparing and detecting the levels of the audio signal and the reference signal and transmitting a comparison signal, and a controlling means for detecting and judging the comparison signal and transmitting a control signal to the volume adjusting means. An audio input level adjusting device comprising: