JPH0693285B2 - Microphone mixing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention comprises two decks in which a single noise reduction circuit is shared, and a reproduction signal of the deck and a source signal other than the deck and a microphone signal. The present invention relates to a microphone mixing device for audio equipment having a microphone mixing function of mixing

(B) Conventional Technology A tape recorder having two decks in a single cabinet, a so-called double deck tape recorder is known. As such a tape recorder, for example, there is one described in JP-A-52-132814, which has a dubbing function of recording a reproduction signal of one deck with the other deck and a reproduction of one deck. Since it can be equipped with a continuous playback function that automatically starts playback of the other deck when finished, it is easy to use and is now widely used.

On the other hand, in some audio equipment, for example, as described in Japanese Utility Model Publication No. 55-146710, the reproduced sound of a magnetic tape and a record is mixed with a singing voice input from a microphone, and the sound is simultaneously emitted from a speaker. There is a karaoke device that has a microphone mixing function so that you can enjoy singing easily. If an audio device having the microphone mixing function is provided with a double deck type tape recorder, a performance signal obtained from one deck is mixed with a singing signal obtained from a microphone, and the signal is recorded by the other recording function. Since it is possible to record on the magnetic tape loaded in the deck, it is convenient to create a new music tape.

By the way, many tape recorders have a noise reduction circuit for reducing noise of the magnetic tape such as hiss noise included in a reproduction signal when the tape recorder is reproduced. The noise reduction circuit reduces the noise of the magnetic tape by performing a recording process of compressing a recording signal at the time of recording and a reproducing process of expanding the reproduction signal at the time of reproduction, which is typical of the noise reducing circuit. A Dolby method is known as a method, and when the noise reduction circuit is provided in the double-decks type tape recorder, a single noise reduction circuit is shared by two decks in a popular tape recorder in terms of cost. Is adopted.

FIG. 2 is a circuit diagram showing an audio device provided with a microphone mixing function in a double-decks type tape recorder that shares such a noise reduction circuit. (1) is a first magnetic head for reproducing the first deck, (2) is a first reproduction amplifier for amplifying a reproduction signal reproduced by the first magnetic head (1), and (3)
Is the second magnetic head for recording and playback of the second deck,
(4) is a second reproduction amplifier for amplifying the reproduction signal reproduced by the second magnetic head (3), (5) is a Dolby type noise reduction circuit for reducing the noise of the magnetic tape, and ( 6 ) is the second
A function switching switch for selecting a source signal to be recorded by a deck, (7) is a microphone, (8) is a microphone amplifier for amplifying a microphone signal obtained from the microphone (7), and (9) is the microphone (7). ) Plug (not shown) is inserted into a microphone jack (not shown) provided in the audio equipment, the microphone output switching switch is closed, and (10) is selected by the function switching switch ( 6 ). The mixing volume for mixing the source signal and the output signal from the microphone amplifier (8) and setting the mixing ratio, ( 11 ) is composed of a power amplifier (12) and a speaker (13), and the function switching switch ( 6). ) Output circuit for monitoring the source signal selected in), (14) is the function switching switch. A recording amplifier for supplying the source signal selected by the switch ( 6 ) to the second magnetic head (3) as a recording signal, and (15) a signal level supplied to the recording amplifier (14) to a predetermined level. ALC (Auto Level Control) that limits and prevents the magnetic tape recorded by the magnetism generated in the second magnetic head (3) from being saturated
Circuits (16) to (18) are recording / reproducing switches that are switched from the P (playback) side to the R (recording) side by the recording operation of the second deck.

The noise reduction circuit (5) has a recording processing means for performing recording processing for noise reduction during recording and a reproduction processing means for performing reproduction processing for noise reduction during reproduction. The recording processing means is for reducing noise by the control signal applied to the terminal (19) when the manual noise reduction switch provided on the front panel of the tape recorder is turned on and the second deck is in the recording state. The reproduction processing means is adapted to perform an operation for noise reduction when the noise reduction switch is turned on and the second deck is not in the recording state. The signal that has passed through the recording processing means is output from the first output terminal (5a) of the noise reduction circuit (5), and the signal that has passed through the reproduction processing means (2) is the second output terminal of the noise reduction circuit (5) ( It is designed to be output from 5b).

When recording a magnetic tape with the second deck and recording a source signal other than the playback signal of the first deck, the playback signal of the record player is supplied according to the source signal to be recorded by the function switching switch ( 6 ). Terminal (6b), terminal (6c) to which the received signal of the tuner is supplied
Alternatively, switch to the terminal (6d) to which the playback signal of the CD player is supplied. Then, the recording operation of the second deck is performed. Then, the movable contacts of the recording / reproducing switches (16) to (18) are switched to the R (recording) side. Therefore, the source signal selected by the function switching switch ( 6 ) is output by the output circuit ( 1
Is supplied to the 1), it is supplied through a recording and reproducing switch (17) to the noise reduction circuit (5). Output circuit ( 11 )
The source signal supplied to is emitted by the speaker (13) and monitored. At this time, the source signal supplied to the noise reduction circuit (5) because the second deck is in the recording state is the first output terminal (5a) via the recording processing means of the noise reduction circuit (5). Output from a recording amplifier (14)
Is supplied to the second magnetic head (3) as a recording signal by superimposing a bias current in the recording amplifier (14). Therefore, recording is performed on the magnetic tape loaded on the second deck, and recording on the second deck is achieved. And
In this case, when the noise reduction switch is turned on, the recording processing means of the noise reduction circuit (5) is activated, so that the recording signal subjected to the recording processing for noise reduction is recorded on the magnetic tape. When the noise reduction switch is turned off, the recording processing means does not operate and becomes a mere linear amplifier, so that the recording signal of the source signal as it is without the recording processing for noise reduction is recorded on the magnetic tape.

Further, when recording the reproduction signal of the first deck with the second deck, that is, during dubbing, the function switching switch ( 6 ) is supplied to the terminal (6a) to which the reproduction signal of the deck is supplied.
The recording operation of the second deck is performed, and the reproduction operation of the first deck is performed. Then, the recording / reproducing switch (16) to (1
In 8), since the movable contact piece is switched to the R side for the recording operation of the second deck, the reproduction signal reproduced by the first magnetic head (1) is the first reproduction amplifier (2) and the line amplifier (20). , And is supplied to the output circuit (11) via the recording / reproducing switch (18) and the function switching switch ( 6 ) and is also supplied to the noise reducing circuit (5) via the recording / reproducing switch (17). The reproduction signal of the first deck supplied to the output circuit ( 11 ) is emitted by the speaker (13) and monitored. At this time, since the second deck is in the recording state, the reproduction signal of the first deck supplied to the noise reduction circuit (5) is first recorded through the recording processing means of the noise reduction circuit (5). The signal is output from the output terminal (5a) and supplied to the recording amplifier (14). The recording amplifier (14) superimposes a bias current on the bias current and supplies the recording signal to the second magnetic head (3). Therefore, the first magnetic tape loaded on the second deck
The reproduction signal of Decki is recorded, and the dubbing recording is achieved.

The above-mentioned device is a microphone which is inserted into the microphone jack provided in the above device at the time of microphone mixing to enjoy singing with the source signal selected by the function switching switch ( 6 ) as the performance signal. The output switching switch (9) is closed. Then, in accordance with the performance sound monitored by the speaker (13), sing to the microphone (7). Then, the singing sound is set as a singing signal via the microphone (7), the microphone amplifier (8) and the microphone output switching switch (9) as a singing signal, and a mixing ratio with the performance signal is set by the mixing volume (10). It is supplied to the power amplifier (12). Therefore, the speaker (13) radiates a sound in which the singing sound is mixed with the performance sound corresponding to the mixed signal in which the performance signal is mixed with the singing signal. On the other hand, at this time,
The mixed signal is supplied to the ALC circuit (15) and the recording / reproducing switch (1).
Is supplied to the noise reduction circuit (5) via the noise reduction circuit (5), and the recording amplifier (14) is passed through the recording processing means of the noise reduction circuit (5).
The mixed signal is recorded on the magnetic tape loaded in the second deck, and a new music tape is created.

(C) Problems to be Solved by the Invention However, in the above-mentioned device, the state in which the noise reduction circuit (5) is used for recording the second deck, that is, the noise reduction circuit (5), is used during dubbing. When the magnetic tape recorded with the recording signal subjected to the recording processing for noise reduction is reproduced by the first deck, the reproduced signal is generated by the noise reduction circuit ( 5)
Is not directly supplied to the output circuit ( 11 ), the correct playback sound is not obtained from the speaker (13), and the performance signal and the recording process are performed to reduce noise. There was a drawback that it was mixed with the unsung singing signal and recorded on the magnetic tape.

The present invention intends to provide a microphone mixing device made in view of the above points.

(D) Means for Solving the Problems The microphone mixing device according to the present invention reproduces the input signal of the output circuit when switched to the first position and reproduces the first deck when switched to the second position. First switching means for supplying signals to the noise reducing circuit, respectively, and an output signal from the recording processing means of the noise reducing circuit when switched to the first position, and the output signal when switched to the second position. Second switching means for supplying the respective input signals of the output circuit to the second recording amplifier are provided.

(E) Operation In the present invention, the recording signal path for microphone mixing with the reproduction signal of the first deck is provided separately from the recording signal path for microphone mixing with other source signals, and the reproduction signal of the first deck is The signal is mixed with the output signal from the microphone amplifier after passing through the reproduction processing means of the noise reduction circuit.

(F) Embodiment FIG. 1 shows an embodiment of the present invention.
A first magnetic head for reproducing the deck, (22) a first reproducing amplifier for amplifying a reproduced signal reproduced by the first magnetic head (21), and (23) a second magnetic head for recording and reproducing the second disk. 2 magnetic heads, (24) a second reproducing amplifier for amplifying a reproduced signal reproduced by the second magnetic head (23), (25) a recording processing means for reproducing a recording process for noise reduction during recording and reproduction. And a reproduction processing means for performing a reproduction processing for noise reduction, and a signal transmitted through the recording processing means has a first output terminal (25
The signal output from a) and passed through the reproduction processing means is the second signal.
In the Dolby type noise reduction circuit output from the output terminal (25b), the reproduction signal of the first or second deck is supplied to the first terminal (26a) and the reproduction signal of the record player is supplied to the second in the (26).
The received signal from the tuner is input to the terminal (26b) at the third terminal (26c).
, The reproduction signal of the CD player is supplied to the fourth terminal (26d), and the function switching switch for selecting the source signal to be recorded at the second deck, (27) is the function switch (28) for selecting the source signal. A switching control circuit for controlling the function switching switch (26) by generating a switching signal according to the operation from the first terminal (27a), (29) is a microphon, (30) is from the microphon (29). A microphone amplifier for amplifying the obtained microphone signal, (31) mixing for mixing the source signal selected by the function switching switch (26) and the output signal from the microphone amplifier (30) and setting a mixing ratio. The volume (32) is the microphone output inserted in the signal path (33) connecting the microphone amplifier (30) and the mixing volume (31). Force switching switch,
( 34 ) comprises a power amplifier (35) and a speaker (36), and the movable contact (31) of the mixing volume (31).
Output circuit for monitoring the signal obtained in a), (3
7) is a recording amplifier for supplying the source signal selected by the function switching switch (26) to the second magnetic head (23) as a recording signal, and (38) is a common terminal (38a) for the noise reduction circuit. (25) input terminal (25c)
The first terminal (38b) is the input terminal of the output circuit ( 34 ), the second terminal (38c) is the output terminal of the first reproduction amplifier (22), and the third terminal (38d) is the second terminal. Playback amplifier (2
The output terminal of 4) has a fourth terminal (38e) connected to the ground as a first switching switch, and (39) has a common terminal (39a) as an input terminal of the recording amplifier (37) and a first terminal (39b). ) Is the first output terminal (25a) of the noise reduction circuit (25), the second terminal (39c) is the input terminal of the output circuit ( 34 ), and the third terminal (39d) is the first reproduction amplifier (). A second switching switch (40) connected to the output terminal of (22), and the first switching switch (38) from the first and second output terminals (41) and (42).
The control signal for switching between the 3rd and 4th output terminals (4
Control signal generation for generating a control signal for switching the second switching switch (39) from 3) and (44) and generating a control signal for switching the microphone output switching switch (32) from the fifth output terminal (45). A circuit (46) for the first switching switch (3) in response to a control signal generated from the first and second output terminals (41) and (42) of the control signal generating circuit (40).
8) is a first switch switching circuit, (47) is the third and fourth output terminals (43) of the control signal generating circuit (40)
And a second switch switching circuit for switching the second switching switch (39) in accordance with a control signal generated from (44), and (48) from the P (playback) side to the R (recording) by the recording operation of the second deck. The recording / playback switch is switched to the side.

The noise reduction circuit (25) is provided on the front panel of the audio device, and is activated / deactivated according to the on / off state of a manually operated noise reduction switch (not shown),
State of the first and second decks such that the recording processing means is used when the second deck is in the recording state and the reproduction processing means is used when the first or second deck is in the reproducing state. A control signal is supplied to the control terminal (49) accordingly.

The control signal generation circuit (40) includes a first reproduction switch (50) which is closed in the reproduction state of the first deck, and a second reproduction switch (51) which is closed in the reproduction state of the second deck. , Recording switch closed in the recording state of the second deck (52)
A first inverter (53) connected to the first regeneration switch (50), a first NOR circuit (54) having one input terminal connected to the inverter (53), and the second regeneration switch. A second inverter (55) connected to the (51), one input end of the inverter (55) is connected, the other input end is connected to the output end of the first NOR circuit (54), First
A second NOR circuit (56) having an output terminal connected to the other input terminal of the NOR circuit (54), and an input terminal connected to each of the first reproduction switch (50) and the recording switch (52). The first AND circuit (57), the third inverter (58) connected to the output terminal of the AND circuit (57), and one input terminal connected to the output terminal of the inverter (58), the recording switch A second AND circuit (59) having the other input terminal connected to (52), and one input terminal connected to the output terminal of the AND circuit (59), and the output terminal of the first NOR circuit (54). A first OR circuit (60) having the other input terminal connected to, and one input terminal connected to the output terminal of the AND circuit (59), and the other output terminal of the second NOR circuit (56). When the high speed reproduction of the first deck and the high speed recording of the second deck are performed with the second OR circuit (61) to which the input terminal is connected The high speed switch (62) that can be switched to the closed state by manual operation and the plug (not shown) of the microphone (29) are closed when the microphone jack (not shown) provided in the audio equipment is inserted. A NAND circuit (64) in which one input terminal is connected to the formed microphone switch (63) and the high speed switch (62), and the other input terminal is connected to the output terminal of the first AND circuit (57). A third AND circuit (65) having one input terminal connected to the output terminal of the NAND circuit (64) and the other input terminal connected to the microphone switch (63), and the first or second deck. One input end is connected to the second terminal (27b) of the switching control circuit (27) that generates an "H" signal when the function switch (28) operated when selecting The other of the output terminals of the third AND circuit (65) And a fourth AND circuit (66) to which the input end is connected.

The control signal generation circuit (40) opens all the first reproduction switch (50), the second reproduction switch (51) and the recording switch (52) in the initial state where the first and second decks are not operated at all. Since it is in the state, the first inverter (5
3), the second inverter (55), both input ends of the first AND circuit (57), and one input end of the second AND circuit (59) are applied with the "L" signal. Therefore, since the "H" signal is applied to one input end of both the first and second NOR circuits (54) and (56), the first and second NOR circuits (54) and (56) Both generate an "L" signal. On the other hand, the "L" signal is generated from both the first and second AND circuits (57) and (59). Therefore, since the "L" signal is applied to both input ends of both the first and second OR circuits (60) and (61), the first and second OR circuits (60) and (61) are applied. Both generate an "L" signal.
That is, in the initial state, the control signal generation circuit (40)
The "L" signals are all generated from the first to third output terminals (41) to (43). From this state, when the first deck is in the regenerating state and the first regenerating switch (50) is closed, the "H" signal is applied to the first inverter (53), and the first NOR circuit (54) Since the "L" signal is applied to both input terminals, the "H" signal is generated from the first NOR circuit (54) and the "H" signal is generated from the first output terminal (41). Will be generated. Further, since the "H" signal is applied to both input terminals of the second NOR circuit (56), the "L" signal is generated from the second NOR circuit (56). On the other hand, the first AND circuit (57) generates the "L" signal because the "H" signal is applied to one input end but the "L" signal is applied to the other input end. Therefore, the "L" signal is generated from both the second and third output terminals (42) and (43).

Next, when only the second deck is in the regenerating state and the second regenerating switch (51) is closed, the second NOR circuit (conversely when the first deck is only in the regenerating state). Since the "L" signal is generated from 54), the "H" signal is generated from the second NOR circuit (56), and the "L" signal is generated from the first AND circuit (57). An "H" signal is generated from the output terminal (42), and an "L" signal is generated from the first and third output terminals (41) and (43).

When both the first and second decks are in the regenerating state and the first and second regenerating switches (50) and (51) are closed, the first and second regenerating switches (50) and (51) are closed according to the decks which are previously in the regenerating state. Signals are generated from the first and second output terminals (41) and (42). That is, the "H" signal is output from one of the first and second NOR circuits (54) and (56) in accordance with the first closed switch of the first and second reproduction switches (50) and (51). Since it is generated, the "H" signal is applied to the other one input end of the first and second NOR circuits (54) and (56), and the above-mentioned switch is closed to the switch that is closed later. The first and second NOR circuits (54) and (56) are not affected.

When the second switch is in the recording state and the recording switch (52) is closed, the first AND circuit (57) receives the "L" signal at one input end and the "H" signal at the other input end. Since the signal is applied, the "L" signal is generated from the first AND circuit (57). Therefore, the "H" signal is applied to both input terminals of the second AND circuit (59), and the second AND circuit (59) generates the "H" signal. Therefore, the "H" signal is generated from both the first and second output terminals (41) and (42), and the "L" signal is generated from the third output terminal (43).

Next, in the state where the second deck is in the recording state, in the dubbing state where the first deck is in the reproducing state,
Since the recording switch (52) and the first reproduction switch (50) are closed, the "H" signal is applied to both input terminals of the first AND circuit (57), and the first AND circuit (57) outputs the signal. An "H" signal is generated. Therefore, the second AND circuit (5
9) The “L” signal is applied to one input terminal of
An "L" signal is generated from the AND circuit (59). On the other hand, as in the case where the first deck is brought into the regenerating state due to the closing of the first regenerating switch (50), the first NOR circuit (5
An "H" signal is generated from 4). Therefore, the first
An "H" signal is generated from the third output terminals (41) and (43), and an "L" signal is generated from the second output terminal (42).

That is, the states of the first and second decks described above, the open / close states of the first reproduction switch (50), the second reproduction switch (51) and the recording switch (52) of the control signal generation circuit (40), To 3 are summarized in relation to the output signals generated from the third output terminals (41) to (43).

By the way, when the signal generated at the third output terminal (43) is applied to one input end of the NAND circuit (64) and the "H" signal is generated from the third output terminal (43), dubbing is performed. Since it is only for the time, the "L" signal is generated from the NAND circuit (64) only in the dubbing state and when the high speed switch (62) is closed. Therefore, the third AND circuit (65) is not in the dubbing state, or the high speed switch (62) is not closed,
And when the microphone switch (63) is closed, it generates an "H" signal. That is, it becomes as shown in FIG. The output signal from the third AND circuit (65) is applied to the fifth output terminal (45) and input to the fourth AND circuit (66). The fourth AND circuit (66) receives the output signal from the second output terminal (27b) of the switching control circuit (27) in addition to the output signal from the third AND circuit (65). When the "H" signal is generated from the third AND circuit (65) from the fourth AND circuit (66) and when the "H" signal is generated from the second output terminal (27b), "H" signal is generated. Generate a signal.

The first switch switching circuit (46) performs the first switching when the control signals generated from the first and second output terminals (41) and (42) of the control signal generating circuit (40) are both "H" signals. The common terminal (38a) of the switch (38) is the first terminal (38b)
In the case of "H" and "L" signals, the common terminal (38a) is the second terminal (38c), and in the case of "L" and "H" signals, the common terminal (38a) is the third terminal. Terminal (3
8d), the common terminal (38a) when both are "L" signals
The first switching switch (38) is switched so that is connected to the fourth terminal (38e) (Fig. 5).

Also, the second switch switching circuit (47) is the first when the control signals generated from the third and fourth output terminals (43) and (44) of the control signal generating circuit (40) are both "H" signals. The common terminal (39a) of the 2-switch switch (39) is the second terminal (39).
In c), the common terminal (39a) is the third terminal (39d) in the case of “H” and “L” signals respectively, and the common terminal (39a) is the first terminal (39b) in other cases. The second switching switch (39) is switched so that it is connected (Fig. 6).

The microphone output switching switch (32) is configured to be closed when the control signal generated from the fifth output terminal (45) of the control signal generating circuit (40) is the "H" signal.

In the above device, when microphone mixing is performed, first insert the plug of the microphone (29) into the microphone jack and insert the microphone (29) into the microphone amplifier (30).
Connect to. After that, it is confirmed that the high speed switch (62) is opened, and the function switch (28) is operated to select the source signal as the desired performance signal. Then, from the first output terminal (27a) of the switching control circuit (27), the function switch (2
A switching signal corresponding to the operation of 8) is generated, and the function switching switch (26) is switched by the switching signal. When the reproduction signal of the first deck is selected as the performance signal by the function switch (28), the function switching switch (26) is connected to the first terminal (26).
Since it is switched to a), the reproduction operation of the first deck is performed thereafter. Then, the reproduction of the magnetic tape is started at the first magnetic head (21). Here, the control signal generation circuit (40)
Since the recording operation of the second deck is not performed, "H" is output from the first and second output terminals (41) and (42), respectively.
And an "L" signal, and an "L" signal is generated from the third output terminal (43). Since the microphone switch (63) is closed by inserting the plug of the microphone (29) into the microphone jack, if the high speed switch (62) is not closed, the output from the fifth output terminal (45) Generates an "H" signal. That is, in the above state, the first switching switch (38) is connected to the common terminal (38
a) is connected to the second terminal (38c), and the microphone output switching switch (32) is closed. Therefore, the reproduction signal reproduced by the first magnetic head (21) is supplied to the first reproduction amplifier (22), the first switching switch (38) and the noise reduction circuit (2).
It is supplied to the output circuit ( 34 ) through the reproduction processing means (5) and the function switching switch (26), and the performance sound corresponding to the reproduction signal reproduced by the first deck is emitted from the speaker (36). Then, if a singing sound is supplied to the microphon (29) in accordance with the performance sound, the singing sound is supplied to the microphone amplifier (30) and the microphone output switching switch (3).
2) as a singing signal via the mixing volume (3
After being mixed with the reproduction signal and the mixing ratio set in 1), it is supplied to the output circuit ( 34 ) as a mixed signal, and the singing sound is mixed with the performance sound from the speaker (36). Is emitted. In this case, since the reproduction signal reproduced by the first deck is passed through the reproduction processing means of the noise reduction circuit (25), the magnetic tape reproduced by the first deck is subjected to recording processing for noise reduction. If it was done,
If the noise reduction switch is turned on to bring the reproduction processing means into the operating state and the reproduction processing for noise reduction is performed, and if the magnetic tape is not subjected to recording processing for noise reduction, noise reduction is performed. In both cases, correct mixing reproduction can be performed by turning off the switch and using it as a mere linear amplifier without operating the reproduction processing means.

At this time, the first switch is selected by the function switch (28) and the "H" signal is generated from the second output terminal (27b) of the switching control circuit (27).
The same output terminal as the fifth output terminal (45) is generated from the fourth output terminal (44). Therefore, in the above case, since the "L" signal is generated from the third output terminal (43), the "H" signal is generated from the fourth output terminal (44), and the second signal is generated.
The common terminal (39a) of the switching switch (39) is the first terminal (3
9b) is connected. In this state, the second
When the deck is recorded, the "H" signal is generated from the third output terminal (43), and the "H" signal is generated from the fourth and fifth output terminals (44) and (45). The second switching switch (39) is connected to the common terminal (39
a) is connected to the second terminal (39c). Therefore, the mixed signal of the reproduction signal of the second deck and the singing signal continues to be generated at the input end of the output circuit ( 34 ), and the mixed sound of the playing sound and the singing sound is radiated from the speaker (36). to continue. on the other hand,
The mixed signal is supplied to the recording amplifier (37) via the ALC circuit (67) and the second switching switch (39). Since the recording / reproducing switch (48) is switched to the R side by the recording operation of the second deck, the mixed signal supplied to the recording amplifier (37) has a bias current in the recording amplifier (37). The second magnetic head (23), which is superimposed and recorded as a recording signal
Is supplied to. Therefore, the mixed signal is recorded on the magnetic tape loaded in the second deck, and a new music tape can be created. In this case, since the level of the mixed signal is limited to a predetermined value or less by the ALC circuit (67), the mixed signal is recorded on the magnetic tape without distortion.

Next, when selecting the playback signal of the record player, the received signal of the tuner or the playback signal of the CD player as the performance signal for microphone mixing, make sure that the high speed switch (62) is open, and By operating the function switch (28) corresponding to the signal, the function switching switch (26) is generated by the switching signal generated from the first output terminal (27a) of the switching control signal (27).
To the desired terminal. Then, the plug of the microphone (29) is connected to the microphone amplifier (30) in the same manner as when the reproduction signal of the first deck is used as the performance signal. Here, the second output terminal (27
Since the performance signal other than the deck is selected from b), the "L" signal is generated, and the control signal generation circuit (40)
Since the microphone switch (63) is only closed,
The "H" signal is generated from the fifth output terminal (45), and the "L" signal is generated from the other first to fourth output terminals (41) to (44). That is, the common terminal (38a) of the first switching switch (38) is the fourth terminal (38).
e), the common terminal (39a) of the second switching switch (39) is connected to the first terminal (39b), and the microphone output switching switch (32) is closed. Therefore, in the mixing volume (31), the performance signal obtained through the function switching switch (26) and the microphone amplifier (3
0) is mixed with the singing signal obtained as a mixed signal and supplied to the output circuit ( 34 ), so that the speaker (36)
A mixed sound of a performance sound and a singing sound is emitted from.

At this time, if the second deck is set to the recording state, the output signals from the first and second output terminals (41) and (42) of the control signal generation circuit (40) change from "L" to "H". Signal, and other third and fourth output terminals (43) and (43)
, And the "H" signal is still generated from the fifth output terminal (45), the common terminal (38a) of the first switching switch (38) is the first terminal (38b). ), The second switching switch (39) is still connected to the common terminal (39a) to the first terminal (39b), and the microphone output switching switch (32) is still in the closed state. To be done. Therefore, the mixed signal of the performance signal supplied through the function switching switch (26) and the singing signal supplied from the microphone amplifier (30) is continuously generated at the input terminal of the output circuit ( 34 ), From (36), a mixed sound of the performance sound and the singing sound continues to be emitted. On the other hand, the mixed signal is supplied to the first switching switch (38) and the noise reduction circuit (2).
It is supplied to the recording amplifier (37) via the recording processing means of 5) and the second switching switch (30). Since the recording / reproducing switch (48) is switched to the R side by the recording operation of the second deck, the mixed signal supplied to the recording amplifier (37) has a bias current in the recording amplifier (37). It is superposed and supplied as a recording signal to the second magnetic head (23). Therefore, the mixed signal is recorded on the magnetic tape loaded in the second deck, and a new music tape can be created. In this case, since the mixed signal is passed through the recording processing means of the noise reduction circuit (25), if the noise reduction switch is turned on, the recording processing means will be in the operating state and loaded into the second deck. When a recording signal is recorded on the magnetic tape for noise reduction, and the noise reduction switch is turned off, the recording processing means becomes a mere linear amplifier in a non-operating state, and the magnetic tape reduces noise. A recording signal without any recording processing means is recorded on a magnetic tape.

Further, the above-mentioned device is effective when performing dubbing.

When dubbing, do not insert the plug of Microphone (29) into the microphone jack, and switch the microphone (63).
Leave open. Then, the recording operation of the second deck is performed, and the reproduction operation of the first deck is performed. Then, the "H" and "L" signals are generated from the first and second output terminals (41) and (42) of the control signal generating circuit (40), respectively. On the other hand, since the microphone switch (63) is in the open state and the "H" signal is generated from the third output terminal (43), the high speed switch (62) is opened and closed from the fifth output terminal (45). Regardless of the state, the "L" signal is always generated. Therefore, the "L" signal is always generated from the fourth output terminal (44) without being influenced by the output signal from the second output terminal (27b) of the switching control circuit (27). Therefore,
The common terminal (38a) of the first switching switch (38) is connected to the second terminal (38c), and the common terminal (39a) of the second switching switch (39) is connected to the third terminal (39d). Also,
The recording / play switch (48) is switched to the R side. Therefore, the reproduction signal reproduced by the first magnetic head (21) is supplied to the recording amplifier (37) through the second switching switch (39), and the reproduction signal is biased by the recording amplifier (37). Since the electric current is superimposed and supplied as a recording signal to the second magnetic head (23), the first magnetic tape loaded in the second deck is first recorded.
The playback signal of Decki is recorded and dubbing is achieved.
On the other hand, the reproduction signal reproduced by the first magnetic head (21) is
Noise reduction circuit (25) via the first switching switch (38)
It is applied to the first terminal (26a) of the function switching switch (26) through the reproduction processing means of (1). Therefore, if the reproduction signal of the first deck is selected as the source signal by the function switch (28), the reproduction is performed. The signal is supplied to the output circuit ( 34 ) through the function switching switch (26). Therefore, the reproduction signal of the first deck can be emitted from the speaker (36) and monitored. In this case, since the reproduction signal of the first deck is supplied to the output circuit ( 34 ) through the reproduction processing means of the noise reduction circuit (25), the magnetic tape reproduced by the first deck is reduced in noise. If the recording process for
If the noise reduction switch is turned on, the reproduction processing means is put into an operating state, the reproduction processing for noise reduction is performed, and if the magnetic tape is not subjected to the recording processing for noise reduction, noise is generated. In both cases, proper monitoring can be performed by turning off the reduction switch and using it as a mere linear amplifier without operating the reproduction processing means. Also,
The reproduction signal of the first deck is supplied to the recording amplifier (37) as it is after passing through the first reproduction amplifier (22), so that the magnetic tape reproduced at the first deck is subjected to recording processing for noise reduction. If it has been recorded, it is recorded in the state where the recording process is applied to the magnetic tape loaded in the second deck as it is, and the magnetic tape reproduced in the first deck is subjected to the recording process for noise reduction. If it is not recorded, it is recorded in a state where the recording process is not applied to the magnetic tape loaded in the second deck as it is.

In particular, in the above-mentioned state, when performing high-speed reproduction of the first deck and high-speed recording of the second deck for high-speed dubbing, the high-speed switch (62) is closed. In this state, the first to fifth output terminals (4) of the control signal generating circuit (40) are closed by closing the high speed switch (62).
Since the output signals generated from 1) to (45) do not change at all, the reproduction signal of the first deck is loaded in the second deck as described above except that the running speed of the magnetic tapes of the first and second decks is fast. It is recorded on the recorded magnetic tape. Similarly to the above, the reproduction signal of the first deck is applied to the first terminal (26a) of the function switching switch (26), but since the reproduction signal is uncomfortable for high speed reproduction, in this case, The source switch other than the reproduction signal may be selected by operating the function switch (28) and using the function switching switch (26). Even in this case, since the recording signal path (68) for dubbing is completely independent of the function switching switch (26), there is no influence on dubbing.

By the way, when the microphone (29) plug is inserted into the microphone jack and the microphone switch (63) is closed in the dubbing state, the fifth output terminal (45) of the control signal generating circuit (40) is connected to the high speed switch (45). 62) generates an "H" signal during normal speed dubbing which is not closed. Therefore, at this time, the microphone output switching switch (32) is closed so that the microphone can be mixed. The fourth output terminal (44) of the control signal generation circuit (40) generates an output signal according to the output signal from the second output terminal (27b) of the switching control circuit (27). Terminal (44)
The common terminal (39a) of the second switching switch (39) is the second or third terminal (39c) or (39d) according to the output signal of
Will be connected to. That is, when the reproduction switch of the first switch is selected by the function switch (28) and the "H" signal is generated from the second output terminal (27b) of the switching control circuit (27), the control signal generating circuit is generated. (40)
Since the “H” signal is generated from the fourth output terminal (44) of the second switching switch (39), the common terminal (39
a) is connected to the second terminal (39c), and the output signal from the microphone amplifier (30) is mixed with the reproduction signal of the first deck to be recorded in the second deck, as described in the microphone mixing. Become. Further, when the source switch other than the reproduction signal of the first deck is selected by the function switch (28) and the "L" signal is generated from the second output terminal (27b) of the switching control circuit (27), Since the "L" signal is generated from the fourth output terminal (44) of the control signal generation circuit (40), the second switching switch (39) at this time.
Common terminal (39a) is connected to the third terminal (39d). Therefore, the source signal selected by the function switching switch (26) is mixed with the output signal from the microphone amplifier (30) and is emitted through the output circuit ( 34 ) and at the same time the first signal is output.
The reproduction signal of the deck is recorded in the second deck as it is through the recording signal path (68).

(G) Effect of the Invention As described above, according to the present invention, when a new music tape is created while enjoying singing while using the reproduction signal of the first deck as a performance signal, the reproduction signal reduces noise. Since it is configured so as to be supplied to the output circuit through the circuit reproduction processing means, even a magnetic tape that has been subjected to recording processing for noise reduction is not subjected to the recording processing. Even if it is a tape, it can be properly monitored and the problem that the performance signal subjected to the recording processing and the singing signal not subjected to the recording processing are mixed and recorded is eliminated.

[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 microphone mixing device, and FIG. 3 is the first and second states of the first and second decks and control signal generating circuits. Third
FIG. 4 is an explanatory view showing the relationship with the output terminal, FIG. 4 is an explanatory view showing the relationship between the third output terminal, the high speed switch, the microphone switch and the fifth output terminal of the control signal generating circuit, and FIG. FIG. 6 is an explanatory diagram showing the relationship between the first and second output terminals of the circuit and the first switching switch, and FIG. 6 is an explanatory diagram showing the relationship between the third and fourth output terminals of the control signal generating circuit and the second switching switch. Is. Description of main drawing numbers (21) …… First magnetic head, (22) …… First reproducing amplifier, (23) …… Second magnetic head, (24) …… Second reproducing amplifier, (25)… … Noise reduction circuit, (26) …… Function switching switch, (27) …… Switching control circuit, (2
9) …… Microphone, (30) …… Microphone amplifier, (3
1) …… Mixing volume, (32) …… Mic output switching switch, ( 34 ) …… Output circuit, (37) …… Recording amplifier, (38) …… First switching switch, (39) …… Second Switching switch, (40) ... Control signal generation circuit.

Claims (1)

[Claims] 1. A first deck having at least a reproducing function and a second deck having a recording function, and the first deck
A noise reduction circuit having recording and reproduction processing means for reducing noise of a magnetic tape in an audio device capable of microphone mixing for mixing a microphone signal with a source signal other than a tape reproduction signal and a tape reproduction signal by a deck A function changeover switch for selecting an output signal from the reproduction processing means of the noise reduction circuit and another source signal; an output circuit for monitoring the source signal selected by the function changeover switch; and a microphone obtained from a microphone. A microphone amplifier for amplifying a signal, a signal output from the microphone amplifier and a source signal selected by the function changeover switch are mixed, and a mixing means provided in the preceding stage of the output circuit and a first position are switched. When the input signal of the output circuit is The tape reproduction signal from the first deck is supplied to each of the noise reduction circuits when switched to the storage position, and the second position is switched when microphone mixing with the tape reproduction signal is performed, and microphone mixing with another source signal is performed. Sometimes switched to the first position
The switching means and the output signal from the recording processing means of the noise reduction circuit when switched to the first position and the input signal of the output circuit when switched to the second position, respectively, are the recording amplifier of the second deck. And a second switching means for switching to the second position during microphone mixing with the tape reproduction signal and switching to the first position during microphone mixing with another source signal. The tape reproduction signal forms a path through the reproduction processing means of the noise reduction circuit during microphone mixing with, and the mixed output from the mixing means produces a recording processing of the noise reduction circuit during microphone mixing with another source signal. A microphone mixing device, characterized in that a path passing through the means is formed.