JPS6326469B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an audio device configured to selectively send either an external input signal or the output of a magnetic reproducing circuit to an output circuit, and aims to improve operability. purpose.

As an example of a conventional acoustic device of this type, an acoustic device for karaoke performance will be described with reference to FIG.

In the figure, 1 is an input terminal for cable broadcasting, and the input terminal 1 is connected to an output terminal 6 via a volume adjustment volume 2, an amplifier 3, a switch 4, and an amplifier 5. Reference numeral 7 denotes a magnetic head for reproducing magnetic tape, and the magnetic head 7 is connected to the input terminal of the amplifier 5 via an amplifier 8.

Reference numeral 9 denotes a detection means for detecting whether or not the magnetic tape reproducing circuit comprising the magnetic head 7 and the amplifier 8 is in operation, and if it is in operation, sends out a control signal for controlling the switch 4 to a cut-off state. .

Therefore, when the magnetic tape reproducing circuit is in operation, the input signal from the cable broadcasting does not appear at the output terminal 6, and conversely, when it is not in operation, the same input signal appears at the output terminal 6.

Here, input terminal 1, volume 2, amplifier 3,
5, 8, magnetic head 7, switches 4, 9, and output terminal 6 constitute a first audio device unit A.

On the other hand, B is a second audio device unit configured similarly to the first audio device unit A,
1' to 9' in the figure have the same functions as 1 to 9 in the first acoustic device unit A, respectively.

Next, the operation of this device will be explained.

Both input terminals 1 and 1' are connected in advance to the same cable broadcasting line. First, let us consider the case where the magnetic tape reproduction output of the first audio device unit A is extracted.

Since the magnetic tape playback circuit of the first audio device unit A is in operation, the switch 4 of the first audio device unit A is in a cut-off state, and the input terminal 1
The input signal from the wired broadcast added to the output terminal 6
Only the magnetic tape playback output is sent to the output terminal 6 without appearing on the output terminal 6.

On the other hand, the switch 4' of the second audio equipment unit B is in a conductive state since the magnetic tape playback circuit of the second audio equipment unit B is not in operation, and therefore the unnecessary wired wire applied to the input terminal 1' is in a conductive state. The broadcast signal is transmitted through volume 2', amplifier 3', switch 4',
The signal is sent to the output terminal 6' via the amplifier 5' and becomes an interfering sound. In order to prevent this unintended interference from occurring, the volume 2' must be turned down each time.

Next, when considering the case where the magnetic tape playback output from the second audio device unit B is taken out, for the same reason as above, in order to prevent the generation of unintended interference sounds, it is necessary to adjust the volume 2 of the audio device unit A each time. must be narrowed down.

In this way, in the conventional configuration, the volume 2,
There was a drawback that 2' had to be adjusted. The present invention aims to eliminate such drawbacks, and aims to eliminate external input signals during magnetic tape playback.
For example, the present invention provides an audio device in which a wired broadcasting signal is transmitted so that the intended reproduced sound is not interfered with.

An embodiment of the present invention will be described below with reference to FIG. FIG. 2 is an electrical system diagram of an audio device that is an embodiment of the present invention.

In the figure, A' indicates the first acoustic device unit;
is an input terminal for wired broadcasting. Input terminal 1 is connected to output terminal 6 via volume 2, amplifier 3, switch 4, and amplifier 5. The magnetic head 7 is connected to the input terminal of the amplifier 5 via an amplifier 8.

9 detects whether or not a magnetic tape reproducing circuit comprising a magnetic head 7 and an amplifier 8 is in operation, and if it is in operation, sends a control signal to cut off the switch 4 via an OR gate 10. 4. The control input terminal 12 is connected to the input terminal of the OR gate 10, and the output terminal of the OR gate 10 is connected to the control output terminal 11.

B indicates a second audio device unit, which includes an input terminal 1', a volume 2', an amplifier 3', a switch 4', an amplifier 5', a magnetic head 7', an amplifier 8', a detection means 9', an OR gate 10', It has the same structure as the audio device unit A, consisting of a control output terminal 11' and a control input terminal 12'.

Further, the control output terminal 11' is connected to the control input terminal 12 via the connection line 13, and the control output terminal 11 is connected to the control input terminal 12' via the connection line 14.
It is connected to the.

Next, the operation of this device will be explained.

Both input terminals 1 and 1' are connected in advance to the same cable broadcasting line.

Now, let us consider the case where the magnetic tape reproduction output of the first audio device unit A' is extracted.

When the magnetic tape reproducing circuit of the first audio device unit A' is in operation, the magnetic tape reproducing output from the magnetic head 7 is sent to the output terminal 6 via the amplifiers 8 and 5. At this time, the control signal sent from the detection means 9 is applied to the switch 4 via the OR gate 10, thereby turning off the switch 4.
Therefore, the input signal from the cable broadcast applied to the input terminal 1 does not appear at the output terminal 6.

The control signal from the detection means 9 is applied to the input terminal of the OR gate 10' via the control output terminal 11, the connecting line 14, and the control input terminal 12'. Therefore, even if the magnetic tape playback circuit of the second audio equipment unit B' is not in operation, the switch 4' of the second audio equipment unit B' is cut off.
The input signal from the cable broadcasting input from the input terminal 1' does not appear at the output terminal 6'.

Also, contrary to the above, the second audio device unit
When taking out the magnetic tape playback output from the magnetic head B', the magnetic tape playback output from the magnetic head 7' is sent to the output terminal 6' via the amplifiers 8' and 5' in the same manner as described above. The input signal from the cable broadcast applied to input terminal 1 as well as the input signal from the cable broadcast applied to input terminal 1 will not appear at the output terminal.

As described above, according to the present invention, it is possible to prevent the occurrence of interference noise due to unnecessary external input signals from other units during magnetic tape playback without having to manually turn the volume down one by one, and the operability is significantly improved. .

[Brief explanation of the drawing]

FIG. 1 is an electrical system diagram of a conventional audio device, and FIG. 2 is an electrical system diagram of an audio device that is an embodiment of the present invention. 1, 1'...Input terminal, 2, 2'...Volume,
3, 3', 5, 5', 8, 8'...Amplifier, 4,
4', 9, 9'... Switch, 6, 6'... Output terminal, 7, 7'... Magnetic head, 10, 10'... OR gate, 11, 11'... Control output terminal, 12,
12'... Control input terminal, 13, 14... Connection line.

Claims (1)

[Claims] 1 detecting whether or not an external input circuit connected to the input side of the output circuit via a switch, a magnetic tape playback circuit connected to the input side of the output circuit, and the magnetic tape playback circuit are in operation; and a first control means for controlling the switch so as to be in a cut-off state only when the magnetic tape reproducing circuit is operating. An audio device comprising second control means that receives a signal from the audio device unit indicating that its magnetic tape reproducing circuit is in operation and turns off its own switch.