JPH0555200U - Assist vocal circuit - Google Patents

Abstract

(57) [Abstract] [Purpose] The present invention provides an assist vocal circuit that can output a vocal signal even when an ON microphone is in use and that can adjust the volume of the vocal signal. [Structure] When the assist vocal is turned on and it becomes an ON microphone
The control voltage of the R, L both channel signal electronic volume 5, 6 is configured to be applied via the variable resistor VR ₁ .

Description

[Detailed description of the device]

[0001]

[Industrial application]

 The present invention relates to an assist vocal circuit, and more particularly to an assist vocal circuit suitable for practicing karaoke by outputting a vocal signal even when a voice is input to a microphone.

[0002]

[Prior art]

 Conventional assist vocal circuits have been provided, for example, as shown in FIG.

In the figure, 1 is an assist vocal ON / OFF signal input terminal, 2 is an R channel signal input terminal, 3 is an L channel signal input terminal, 4 is a MIX output terminal, 5 is an electronic volume for an R channel signal, 6 is an electronic volume for L channel signal, 7 is a microphone input detection circuit, 8 is a microphone, 9 is a MIX circuit _, Q ₁ and Q ₂ are transistors, 10 is an operational amplifier, D ₁ and D ₂ are diodes, R ₁ and R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ and R ₈ are resistors.

As a circuit configuration, the assist vocal ON / OFF signal input terminal 1 is connected to the base of the transistor Q ₁ , and the collector is connected to the power supply voltage Vcc via the resistor R ₇ and the anode of the diode D ₁ is connected. The cathode side of the diode D ₁ is connected to the base of the transistor Q ₂ via the resistor R ₉ , and the resistor R ₈ is connected to the ground.

The microphone 8 is connected to the microphone input detection circuit 7, and the output of the microphone input detection circuit 7 is a so-called diode OR circuit in which the cathode side is connected to the cathode side of the diode D ₁ via the diode D _2. Is configured.

The collector side of the transistor Q ₂ is grounded through the resistor R ₁ to the power supply voltage Vcc, the emitter side is grounded, and the collector is grounded through the resistor R ₂ and the electron for the R channel signal is supplied. It is connected to the control terminal of the volume 5 and to the inverting input terminal of the operational amplifier 10 via a resistor R ₅ .

A voltage divided by a resistor R ₃ and a resistor R ₄ connected between the power supply voltage Vcc and the ground is applied to the non-inverting input terminal of the operational amplifier 10, and the inverted input of the operational amplifier 10 is further applied. A resistor R ₆ is connected between the terminal and the output terminal, and the output terminal is connected to the control terminal of the L-channel signal electronic volume 6.

On the other hand, the R-channel signal electronic volume 5 is connected to the R-channel signal input terminal 2 on the input side, and the L-channel signal electronic volume 6 is connected to the L-channel signal input terminal 3 on the input side. The output sides of both electronic potentiometers 5 and 6 are connected to the MIX circuit 9, and the output of the MIX circuit 9 is connected to the MIX output terminal 4. The assist vocal ON / OFF signal input terminal 1 can be equipped with an assist vocal ON / OFF switch.

Both channel signal electronic potentiometers 5 and 6 are controlled to output a signal of 0% when the control voltage is 0 ^V and to output a signal of 100% when the control voltage is the power supply voltage Vcc. There is.

As for the operation of the circuit configured as described above, the assist vocal ON / OFF input terminal 1 receives a voltage of 5 ^V when the assist vocal ON / OFF switch is ON and 0 ^V or less when OFF. For example, when the assist vocal is OFF, that is, 0 ^V or less is applied to the assist vocal ON / OFF signal input terminal 1, the transistor Q ₁ is turned off, so that the diode D ₁ is forward biased and the transistor Q ₂ The power supply voltage Vcc is applied to the base of the resistor via the resistor R _9, and the transistor Q ₂ is turned on.

Therefore, the control voltage of the electronic volume 5 for the R channel signal is 0_VIn addition, the operational amplifier 10 becomes a non-inverting circuit and the power supply voltage Vcc is added to the control voltage of the L channel signal electronic volume 6, and the L channel signal electronic volume 6 is changed so as to output 100% of the L channel signal. Since the R channel signal electronic volume 5 side functions to set the R channel signal to 0%, the MIX circuit 9 outputs 100% of the L channel signal, and the MIX output terminal 4 sends the circuit of the next stage. As a karaoke operation, the voice sound from the microphone 8 is added only to the accompaniment signal. In addition, the operational amplifier 10 has a resistor R so as to invert and output with reference to the voltage of 1/2 Vcc.₃, R _Four , R_FiveAnd R₆Has been set.

Next, when 5 ^V is applied to the assist vocal ON / OFF signal input terminal 1 and the assist vocal is turned on, the transistor Q ₁ is turned on and the diode D ₁ is reverse biased. The ON / OFF state of the transistor Q ₂ depends on the presence / absence of output of the microphone input detection circuit 7. When voice is input from the microphone 8 and +5 ^V is output from the microphone input detection circuit 7 (hereinafter referred to as ON microphone). Because the diode D ₂ becomes a forward bias and turns on the transistor Q ₂ , the MIX output terminal 4 receives only the L channel signal, that is, the accompaniment signal, as in the case where the assist vocal switch is turned off. % Is output.

When there is no input from the microphone 8 and the microphone input detection circuit 7 outputs 0 ^V (hereinafter referred to as an OFF microphone), the diode D ₂ is reverse-biased and the base of the transistor Q ₂ is at the ground level. Therefore, the control voltage of the electronic volume 5 for the R channel signal is Vcc × R ₂ / (R ₁ + R ₂ ) (however,> 1/2 Vcc), and the control voltage of the electronic volume 6 for the L channel signal is an operational amplifier. 10 acts as a differential amplifier and becomes Vcc- {Vcc × R ₂ / (R ₁ + R ₂ )} (that is, <1/2 Vcc), and the MIX output terminal 4 is R channel signal> L channel signal. A certain R channel and L channel MIX signal is output. The resistors R ₁ and R ₂ are set so that the voltage at their connection point is in the range of 1/2 Vcc to Vcc when the transistor Q ₂ is in the OFF state.

Note that many karaoke source signals are composed of an L channel signal for karaoke only and an R signal for karaoke + vocal, but there are some sources for which the R channel signal is only for vocals. If only 100% output is used, the MIX output is distributed as described above in order to avoid the problem that the color fades out.

[0015]

[Problems to be solved by the device]

 However, in the above-mentioned conventional example, as shown in FIG. 2, the R channel signal vocal is output only when the assist vocal switch is ON and there is no input to the microphone, and the vocal signal of the R channel signal is output. Since the volume is fixed, it is very difficult for karaoke practitioners to use.

The present invention has been made in view of the above points, and an object thereof is to solve the drawbacks of the conventional example, to output a vocal signal even when the microphone is ON, and to adjust its volume. It is in the area of providing an assisted vocal circuit that can be done.

[0017]

[Means for Solving the Problems]

 The assisted vocal circuit of this invention is an electronic volume (R) that controls the volume of the right channel with a stereo signal of a karaoke source that sends a vocal signal to the right channel and an accompaniment signal to the left channel. An electronic volume (L) that controls the volume of the left channel, an assist vocal switch that starts control of a variable amount of both electronic volumes, a microphone input detection circuit that detects voice input to the microphone, and a microphone input. Connected between the switch circuit (A) that turns ON / OFF depending on the presence or absence of the output signal of the detection circuit, the variable resistor connected in series with the switch circuit (A), and the sliding terminal of the variable resistor and ground. A switch circuit (B) that turns ON / OFF by the ON / OFF signal of the assist vocal switch is provided, and only the accompaniment signal of the left channel when the assist vocal switch is OFF. Outputs, which is constituted so as to control both the electronic volumes so can be arbitrarily set mixing ratio of the assist vocal switch ON state whether a tested out with both channel signals of the audio input to the microphone.

[0018]

[Action]

 According to this invention, a vocal signal is sent to the right channel, and an accompaniment signal is sent to the left channel. An electronic volume (R) that controls the volume of the right channel by the stereo signal of the karaoke source and a volume of the left channel are controlled. Control volume, an assist vocal switch that starts control of the variable volume of both electronic volumes, a microphone input detection circuit that detects voice input to the microphone, and an output of the microphone input detection circuit. A switch circuit (A) that turns ON / OFF depending on the presence or absence of a signal, a variable resistor connected in series with the switch circuit (A), and an assist connected between the sliding terminal and the ground of the variable resistor. A switch circuit (B) that turns ON / OFF according to the ON / OFF signal of the vocal switch is provided.When the assist vocal switch is OFF, only the accompaniment signal of the left channel is output, When the vocal switch is ON, the presence or absence of voice input to the microphone is detected, and both electronic volumes are controlled so that the mixing ratio of both channel signals can be set arbitrarily. It becomes possible to output a vocal signal and to adjust the volume of the vocal signal by a variable resistor.

[0019]

【Example】

 An embodiment of the assist vocal circuit according to the present invention will be described with reference to FIG. The same parts as those of the conventional example are designated by the same reference numerals and the description thereof will be omitted.

FIG. 1 is a circuit diagram showing an embodiment of the present invention. In the figure, Q ₂ and Q ₃ are transistors, and VR ₁ is a variable resistor.

The configuration of the circuit is the output of the microphone input detection circuit 7 is directly connected to the base of the transistor Q _2, the power supply voltage to the collector of the transistor Q ₂ is through a resistor R ₁ and the variable resistor VR ₁ in series Vcc is connected.

The variable resistor VR ₁ sliding pin control terminal and an operational amplifier in the conventional example as well as R-channel signal for the electronic volume 5 is connected to the connection side of the resistor R ₁ of the variable resistor VR ₁ It is connected to the inverting input terminal of 10 via a resistor R ₅ .

On the other hand, the assist vocal ON / OFF signal input terminal 1 is connected to the base of Toranshisuta Q _3, the collector of the transistor Q ₃ are also to ground, the emitter is respectively connected to the sliding terminal of the variable resistor VR ₁ ing.

As the operation of the circuit configured as described above, 0 ^V is applied to the assist vocal ON / OFF signal input terminal 1, that is, when the assist vocal switch is OFF, the transistor Q ₃ is in the ON state, similar to the conventional example. The L channel signal electronic volume 6 side passes a 100% signal, and the R channel signal volume 5 side outputs a 0% signal, regardless of whether the microphone input detection circuit 7 outputs at this time.

When +5 ^V is applied to the assist vocal ON / OFF signal input terminal 1, that is, when the assist vocal ON signal is applied, the transistor Q ₃ is turned off. The microphone input detection circuit 7 outputs 0 ^V , that is, when the microphone is OFF, the transistor Q ₂ is also in the OFF state, and the control voltage of the R channel signal electronic volume 5 is Vcc × R ₂ / (R ₁ + R ₂ ), the control voltage of the L channel signal electronic volume 6 becomes Vcc- {Vcc × R ₂ / (R ₁ + R ₂ )}, and the R channel signal at the MIX output terminal 4> The MIX signal which becomes the L channel signal is output as in the conventional case.

Since the transistor Q ₂ is turned on when the microphone is ON, the control voltage of the electronic potentiometers 5 and 6 for R and L channel signals is varied by adjusting the variable resistor VR ₁ connected to the collector of the transistor Q _2. Therefore, the MIX signal in which the R channel signal is varied is output to the MIX output terminal 4.

In this way, the R channel signal, that is, the vocal signal can be output even when the microphone is ON, and the volume level of the vocal signal can be adjusted.

[0028]

[Effect of the device]

 Since the assist vocal circuit according to the present invention is configured as described above, it has the following effects.

Since the vocal as a karaoke source can also be output together with the ON microphone, the amount of vocal can be adjusted according to the progress level and taste of the karaoke practitioner.

Moreover, it has an excellent feature that the circuit can be made simpler and the implementation is easy.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an embodiment of the present invention.

FIG. 2 is a circuit diagram showing a conventional assist vocal circuit.

[Explanation of symbols]

 1 Assist vocal ON / OFF signal input terminal 2 R channel signal input terminal 3 L channel signal input terminal 4 MIX output terminal 5 R channel signal electronic volume 6 L channel signal electronic volume 7 Microphone input detection circuit 8 Microphone 9 MIX circuit 10 Operational amplifier

Claims (1)

[Scope of utility model registration request] 1. An electronic volume (R) for controlling the volume of the right channel and a volume of the left channel by a stereo signal of a karaoke source in which a vocal signal is sent to the right channel and an accompaniment signal is sent to the left channel. An electronic volume to be controlled (L), an assist vocal switch for starting control of a variable amount of the both electronic volumes, a microphone input detection circuit for detecting a voice input to a microphone,
A switch circuit (A) that turns ON / OFF depending on the presence or absence of the output signal of the microphone input detection circuit, a variable resistor connected in series with the switch circuit (A), and between the sliding terminal of the variable resistor and ground. A switch circuit (B) that turns ON / OFF according to the ON / OFF signal of the connected assist vocal switch is provided.When the assist vocal switch is OFF, only the accompaniment signal of the left channel is output, and when the assist vocal switch is ON, the sound to be input to the microphone. An assist vocal circuit characterized in that it is configured to control both electronic volumes so that the ratio of mixing of both channel signals can be arbitrarily set by detecting the presence or absence of.