JP2607471Y2 - Audio visual amplifier - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an audio / visual amplifier.

[0002]

2. Description of the Related Art An audio-visual system (hereinafter, referred to as an audio-visual system) that combines audio and visual.
Also called AV system. ) Are, for example, as shown in FIG. 4, an audio-visual amplifier (hereinafter, also referred to as an AV amplifier) 81 and a satellite broadcast tuner (hereinafter, B).
Also called S tuner. ) 82, a laser disc player (hereinafter also referred to as an LD player) 83, a video tape recorder (hereinafter also referred to as a VTR) 84, a television monitor (hereinafter also referred to as a TV monitor) having an audio output amplifier 85A and a speaker 85B. .) 85, a pair of front speakers 86 and 87 and rear speakers 88 and 89 addressed to a pair of left and right sides.

In the AV amplifier 81, the BS tuner 8
2. The sound signals from the LD player 83 and the VTR 84
The signals are input to a surround processor 92 and the like via an audio signal input switch 91 of an audio signal switching device 90, and are output to front speakers 86 and 87 and a rear speaker 88 via front amplifiers 93 and 94 and rear amplifiers 95 and 96. , 89 are driven, and the audio signal input to the AV amplifier 81 is output to the VTR 84 via the audio signal output switch 97 of the audio signal switching device 90.

In the AV amplifier 81, video signals from a BS tuner 82, an LD player 83, and a VTR 84 are supplied to a video signal input switch 99 of a video signal switching device 98.
Is output to the TV monitor 85 via the
The video signal input to the amplifier 81 is supplied to the VTR 8 via the video signal output switch 100 of the video signal switching device 98.
4 is output.

Further, the AV amplifier 81 supplies power to the surround processor 92, each of the amplifiers 93 to 96 and each of the signal switching devices 90 and 98, and also to the main power supply 102 having the main power switch 101 and the microcomputer 103. Standby power supply 104. Microcomputer 103
, The input selector information from the input selector 105, the mode information from the surround mode selector 106, and the timer recording information from the timer recording setting device 107, respectively, and the microcomputer 103 sets the signal switching devices 90, 98, etc. Control. The input selector information is information for selecting an audio / visual device (hereinafter, referred to as an AV device) to be input. The mode information is information for selecting surround reproduction and normal sound reproduction such as two-channel stereo reproduction or monaural reproduction.

[0006]

As described above, the TV monitor 85 is generally provided with an audio output amplifier 85A and a speaker 85B capable of normal sound reproduction such as two-channel stereo reproduction or monaural reproduction. I have. Therefore, when normal sound reproduction is performed instead of surround reproduction when the TV monitor 85 is used, the front amplifiers 93 and 94 of the AV amplifier 81 and the front speakers 86 and 87 connected thereto need not be used. .

However, conventionally, the AV amplifier 81 does not have an audio signal output terminal for outputting an audio signal to the TV monitor 85. Therefore, when the TV monitor 85 is used, even when the normal sound reproduction is performed instead of the surround reproduction, the TV monitor 85 is used.
The fact is that the front amplifiers 93 and 94 of the AV amplifier 81 and the front speakers 86 and 87 connected thereto have to be used without using the audio output amplifier 85A and the speaker 85B. .

Also, when dubbing from the LD player 83 to the VTR 84, or when leaving home or at midnight, the TV monitor 8
In the case where timer recording is performed without using the TV receiver 5, the surround processor 92 of the AV amplifier 81 and each amplifier 93
Since the powers 96 to 96 are not used, it is not necessary to supply power to them, but there is also a problem that power is wasted because power is supplied. An object of the present invention is to provide an audio-visual amplifier that can solve the above problem.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is characterized in that audio signals and video signals from a plurality of audiovisual devices having an audio signal output circuit and a video signal output circuit. A plurality of audio signal input terminals and a video signal input terminal to which the audio signal is input, a surround processor capable of processing the input audio signal and outputting a surround signal, and a plurality of audio signal input terminals and a surround processor. An audio signal input switch connected to an audio signal input terminal selected by an input selector and a surround processor, a surround amplifier connected to a surround processor to drive a surround speaker, and a video signal output to a TV monitor TV video signal output terminal, a plurality of video signal input terminals, and a TV video signal A video signal input switch interposed between the input terminals and connecting the video signal input terminal selected by the input selector to the video signal output terminal for TV, and control means for controlling the audio signal input switch and the video signal input switch And a power supply circuit for supplying power to the surround processor and the surround amplifier, and a power supply circuit for supplying power to the control means, and an audio signal output terminal for an external speaker that outputs an audio signal to an external speaker via the external amplifier. , Is interposed between the output side of the audio signal input switch and the surround processor and the audio signal output terminal for external speaker, and is controlled by the control means, regardless of whether an external amplifier is connected to the audio signal output terminal for external speaker. The output side of the audio signal input switch to the sound for the surround processor and external speakers. There the inner and outer output changeover switch selectively connectable to one of the signal output terminal, in that provided with the acoustic output power switch for opening and closing the power supply circuit of the surround processor and surround amplifier.
The internal / external output switch and the audio output power switch are linked, and when the output side of the audio signal input switch and the audio signal output terminal for TV are connected by the internal / external output switch, the audio output power switch is turned off. In some cases,

[0010]

When the input selector is operated to select an AV device, the audio signal input switch and the video signal input switch are operated, and the audio signal and the video signal from the selected AV device are input to the AV amplifier. The video signal is output to a TV monitor, and the TV monitor reproduces the video. Also, by operating the internal / external output changeover switch to connect the output side of the audio signal input switch to the surround processor and turning on the audio output power switch, the audio signal from the selected AV device can be output. The signal is input to the surround processor via the internal / external output switch. The surround processor processes the input audio signal and outputs a surround signal. In response to the output, the surround speakers are driven to perform surround reproduction.

If the output side of the audio signal input switch is connected to the external audio signal output terminal by operating the internal / external output changeover switch, the audio signal from the selected AV device can be switched between the internal and external output switches. The sound is output to the TV monitor via the switch, whereby the sound can be reproduced by the sound output amplifier and the speaker of the TV monitor. In the above case, since the surround processor and the surround speaker of the AV amplifier are not used, the sound output power switch is turned off. In addition, when performing timer recording without using the TV monitor at the time of absence or at midnight, the sound output power switch is turned off in advance, and at the time of timer recording, the surround processor and each surround amplifier are connected. Should not be powered.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIG. FIG. 1 shows an audio-visual system (AV system). The AV system includes an audio-visual amplifier (AV amplifier) 1, a satellite broadcast tuner (BS tuner) 2, a laser disk player (LD player) 3, and a video tape recorder. (VTR)
4, a television monitor (TV monitor) 5, a pair of left and right front speakers 6, 7 and rear speakers 8, 9, which are exemplified as surround speakers. The TV monitor 5 includes an audio output amplifier (external amplifier) 5A and a speaker (external speaker) 5B capable of reproducing normal sound such as two-channel stereo reproduction or monaural reproduction.

By the way, the AV amplifier 1 comprises: 1. Sound signals from the BS tuner 2, the LD player 3, and the VTR 4 are input to the BS sound signal input terminal 11, the LD sound signal input terminal 12, and the VTR sound signal input terminal 13, respectively. 2. BS video signal input terminal 15, LD video signal input terminal 16, and VTR video signal input terminal 17, to which video signals from BS tuner 2, LD player 3, and VTR 4 are input, respectively. An audio signal output terminal 19 for VTR and an audio signal output terminal for external speakers (hereinafter, referred to as an external audio signal output terminal) for outputting an audio signal from the AV amplifier 1 to the VTR 4 and the amplifier 5A of the TV monitor 5, respectively. (Abbreviated as terminal) 2
0 and 4. From the AV amplifier 1 to the VTR 4 and TV monitor 5,
4. A video signal output terminal 21 for VTR and a video signal output terminal 22 for TV for outputting a video signal, respectively. 5. a surround processor 24; A pair of left and right front amplifiers 26 and 27 and rear amplifiers 28 and 29 exemplified as surround amplifiers
And 7. 7. an audio signal switching device 31; 8. a video signal switching device 33; 9. Main power transformer 35 and standby power transformer 36 Main power switch 38 and main power button 3
9. and 11. 11. an audio output power switch 41 and an audio output power button 42; 12. an input selector 44; 13. a surround mode selector 46; 14. a timer recording setting device 48; And a microcomputer 50.

The surround processor 24 processes an input audio signal and outputs a surround signal during surround reproduction. Left and right front amplifiers 26, 27
The rear amplifiers 28 and 29 are connected to the surround processor 24 via the volumes 52 to 55, respectively, and are also connected to the corresponding front speakers 6, 7 and the rear speakers 8, 9, respectively. The audio signal switching device 31 includes an audio signal input switch 57, an internal / external output selection switch 58, and an audio signal output switch 59.

An audio signal input switch 57 selects an audio signal to be input to the AV amplifier 1, and is used for BS and L.
The sound signal input terminals 11 to 13 for D and VTR are interposed between the internal / external output switch 58. The sound signal input switch 57 includes first, second, and third terminals 1A, 2A, and 3A connected to BS, LD, and VTR sound signal input terminals 11 to 13, respectively. 58 and the first to third terminals 1A, 2
A and a switch section 4A selectively connected to the switch section 3A.

The internal / external output changeover switch 58 converts the audio signal input to the AV amplifier 1 into a surround processor 24.
Alternatively, the audio signal is selectively output to the TV monitor 5 and is interposed between the output side of the audio signal input switch 57 and the surround processor 24 and the external audio signal output terminal 20. The internal / external output changeover switch 58 includes an IN terminal 61 connected to the surround processor 24, an OUT terminal 62 connected to the external audio signal output terminal 20, and an IN terminal 61 connected to the output side of the audio signal input switch 57. Alternatively, a switch unit 63 selectively connected to the OUT terminal 62
And During surround reproduction, the switch 63 is connected to the IN terminal 61, and during normal sound reproduction when the TV monitor 5 is used, the switch 63 is connected to the OUT terminal 62.
Connected to.

An audio signal output switch 59 selects whether or not to output an audio signal from the AV amplifier 1 to the VTR 4.
It is interposed between the R sound signal output terminals 19. The audio signal output switch 59 is connected to the VTR audio signal output terminal 19.
, A third terminal 3B that does not output any audio signal, and a first to third terminal 1B, connected to the output side of the audio signal input switch 57.
And a switch section 4B selectively connected to 2B and 3B.

The video signal switching device 33 has a video signal input switch 65 and a video signal output switch 66.
The video signal input switch 65 selects a video signal input to the AV amplifier 1, and is used for BS, LD, and VT.
It is interposed between the R video signal input terminals 15 to 17 and the TV video signal output terminal 22. The video signal input switch 65 includes first, second, and third terminals 1C, 2C, and 3C connected to video signal input terminals 15 to 17 for BS, LD, and VTR, respectively, and a video signal for TV. A switch section 4C connected to the output terminal 22 and selectively connected to the first to third terminals 1C, 2C, 3C.

The video signal output switch 66 is used to select whether or not to output a video signal from the AV amplifier 1 to the VTR 4. The output side of the video signal input switch 65 and the VT
It is interposed between the R video signal output terminals 21. The video signal output switch 66 is connected to the VTR video signal output terminal 21.
, A third terminal 3D not outputting any video signal, and a first to third terminal 1D, connected to the output side of the video signal input switch 65.
And a switch unit 4D selectively connected to 2D and 3D.

The audio signal input switch 57, the audio signal output switch 59, the video signal input switch 65, and the video signal output switch 66 are interlocked with each other, and the switch section 4A of each of the switches 57, 59, 65, 66 is provided. ~ 4D
Terminal 1 of the same name of each switch 57, 59, 65, 66
A to 1D, 2A to 2D, and 3A to 3D. That is, the switch unit 4A of the audio signal input switch 57 is
When connected to the terminal 1A, the other switches 59, 6
5, 66 switch sections 4B to 4D also have first terminals 1B to 1D.
Connected to.

The main power supply transformer 35 serves as a main power supply for the AV amplifier 1, and the standby power supply transformer 36
Each of the transformers 35 and 3 serves as a power supply for the microcomputer 50.
6 is connected to a commercial AC power supply via a plug 68 or the like. In the primary circuit of the main power transformer 35, a main power switch 38 is provided.
5 is provided in series with the primary winding 69. The main power transformer 35 has a secondary winding 70 for sound output and a secondary winding 71 for the switching device. Secondary winding 70 for sound output
Is connected to a surround processor 24 via a rectifier circuit 72 and an audio output power switch 41 for opening and closing the power supply circuit.
Each front amplifier 26, 27 and each rear amplifier 2
Supply direct current to 8,29. The sound output power switch 41 is turned on during surround reproduction, and turned off during normal sound reproduction using the TV monitor 5. The switching device secondary winding 71 supplies a direct current to the audio signal switching device 31 and the video signal switching device 33 via the rectifier circuit 73. The standby power transformer 36 supplies a direct current to the microcomputer 50 via the rectifier circuit 75.

The main power button 39 outputs power information for turning on / off the main power switch 38.
The sound output power button 42 is
Outputs power information for turning on / off. The input selector 44 includes a BS tuner 2, an LD player 3, a V
From among the TRs 4, an AV device that inputs an audio signal and a video signal to the AV amplifier 1 is selected, and input selector information is output.

The surround mode selector 46 selects between surround reproduction and normal sound reproduction using the TV monitor 5, and outputs mode information. The timer recording setting device 48 sets timer recording information in the microcomputer 50. The timer recording information includes source AV device information for outputting audio signals and video signals, recorded AV device information for performing a recording operation, recording start time, and recording start time. It consists of time information about the recording stop time.

The microcomputer 50 serves as control means, and includes a central processing circuit (hereinafter abbreviated as CPU), a read-only memory (hereinafter abbreviated as ROM) storing a control program, and It is composed of a random access memory (hereinafter abbreviated as RAM) for storing variables and the like necessary for processing. The CPU receives power information from the main power button 39 and the sound output power button 42, input selector information from the input selector 44, mode information from the surround mode selector 46, and timer recording information from the timer recording setting device 48. Thus, the main power switch 38, the audio output power switch 41, the audio signal switching device 31, the video signal switching device 33 and the like are controlled. The timer recording information is stored in the RAM.

According to the embodiment configured as described above, the microcomputer 50 is always supplied with power from the standby power transformer 36, and the sound output power switch 41 is normally in the ON state. When the main power button 39 is turned on while the main power switch 38 of the AV amplifier 1 is turned off and the AV amplifier 1 is in the power off state, the power-on information from the main power button 39 is transmitted to the microcomputer 50. Is turned on, the main power switch 38 is turned on, and the surround processor 24 and each amplifier 2 are output from the sound output secondary winding 70 of the main power transformer 35.
6 to 29 and the main power transformer 35
From the switching device secondary winding 71 to the acoustic signal switching device 31
Is supplied to the video signal switching device 33 and the AV amplifier 1
The entire power is turned on.

If the main power button 39 is turned off when the entire AV amplifier 1 is in the power-on state, power-off information from the main power button 39 is input to the microcomputer 50, and the main power switch 38 is turned off. Operated,
Power supply to the surround processor 24, the amplifier audio signal switching devices 31, and the video signal switching devices 33 is stopped.
Then, when the entire AV amplifier 1 is in the power-on state,
By operating the input selector 44, the BS tuner 2, L
When an AV device that inputs an audio signal and a video signal to the AV amplifier 1 is selected from the D player 3 and the VTR 4, the input selector information is output to the microcomputer 50.

Thus, according to the input selector information, the microcomputer 50 operates the audio signal input switch 57 and the audio signal output switch 59 of the audio signal switching device 31 and the video signal input switch 65 and the image signal of the video signal switching device 33. The switching operation is performed in conjunction with the output switch 66. For example, when the BS tuner 2 is selected by the input selector 44, the switch units 4A to 4D of the switches 57, 59, 65, and 66 are connected to the first terminals 1A to 1D.
If the D player 3 is selected, the switch units 4A to 4D are connected to the second terminals 2A to 2D, and if the VTR 4 is selected,
Switch units 4A to 4D are connected to third terminals 3A to 3D.

By switching the audio signal input switch 57 and the video signal input switch 65, the audio signal from the BS tuner 2, the LD player 3, or the VTR 4 is transferred from the audio signal input switch 57 to the internal / external output switch 58. Output and BS tuner 2, L
A video signal from the D player 3 or the VTR 4 is output from the video signal input switch 65 to the TV monitor 5,
If you turn on the V monitor 5, the TV monitor 5
Thus, video can be reproduced.

The input selector 44 controls the VTR 4
Are selected, switch sections 4B and 4D of audio signal output switch 59 and video signal output switch 66 are selected.
Is connected to the first terminal 1B, 1D or the second terminal 2B, 2D, so that the audio signal output from the audio signal input switch 57 to the audio signal output switch 59 and the video signal from the video signal input switch 65 The video signal output to the output switch 66 is output to the VTR 4 and can be recorded on the VTR 4. The VT is set by the input selector 44.
When R4 is selected, the switch units 4B and 4D of the audio signal output switch 59 and the video signal output switch 66
Is connected to the third terminals 3B and 3D. Thereby, V
The audio signal and the video signal output from the TR 4 to the AV amplifier 1 are not output to the VTR 4 and the formation of a loop (oscillation) can be prevented.

After operating the input selector 44, the surround mode selector 46 is operated to select either surround reproduction or normal sound reproduction such as 2-channel stereo reproduction or monaural reproduction using the TV monitor 5. For example, mode information from the surround mode selector 46 is output to the microcomputer 50. Thereby, the microcomputer 50 switches the inside / outside output switching switch 58 and the audio output power switch 41 of the audio signal switching device 31 in conjunction with each other according to the mode information.

For example, the surround mode selector 46
When the surround reproduction is selected, the switch unit 63 of the internal / external output changeover switch 58 is connected to the IN terminal 61 and maintains the sound output power switch 41 in the ON state. Thus, the audio signal input to the switch 63 of the internal / external output changeover switch 58 is input to the surround processor 24, and the surround processor 24 processes the input audio signal and outputs a surround signal. In accordance with this output, each front amplifier 26, 27
And the respective front speakers 6, 7 and the respective rear speakers 8, 9 are driven via the respective rear amplifiers 28, 29,
Surround playback is performed.

If the surround mode selector 46 selects normal sound reproduction such as two-channel stereo reproduction or monaural reproduction using the TV monitor 5, the switch 63 of the internal / external output switch 58 is connected to the OUT terminal 62. And the sound output power switch 41
Is turned off. As a result, the audio signal input to the switch section 63 of the internal / external output changeover switch 58 is output to the TV monitor 5 via the external audio signal output terminal 22, and is normally output by the amplifier 5A and the speaker 5B of the TV monitor 5. Sound reproduction is performed. In the above case,
Since the sound output power switch 41 of the AV amplifier 1 is turned off and power is not supplied to the surround processor 24 and each surround amplifier, power can be saved, and the front speakers 6, 7 and the rear speakers 8, 9 are inadvertently turned off. There is no danger of driving and sound output.

Further, when timer recording is performed during absence or at midnight, the timer recording setting device 48 is used.
Thus, the timer recording information is set in the microcomputer 50. As a result, when the recording start time comes, the main power switch 38 is turned on, and power is supplied from the switching device secondary winding 71 of the main power transformer 35 to the audio signal switching device 31 and the video signal switching device 33. Also, according to the source AV device information of the timer recording information, the switch sections 4A to 4D of the audio signal input switch 57, the audio signal output switch 59, the video signal input switch 65, and the video signal output switch 66 are operated, and the BS tuner 2 is turned on. Or
The audio signal and the video signal from the LD player 3 are input to the VTR 4 via the AV amplifier 1 and timer recording is performed. Then, when the recording stop time comes, the main power switch 38 is turned off.

In the above case, if the sound output power button 42 is turned off in advance and the microcomputer 50 turns off the sound output power switch 41, the surround processor 24 and each amplifier 26
２９29 are not supplied with power and can save power. Although omitted in the above description, the surround mode selector 46
Normal sound reproduction such as 2-channel stereo reproduction or monaural reproduction using the AV amplifier 1 can be selected. In the above case, the sound signal input to the AV amplifier 1 is not input to the surround processor 24 and is not shown. The signals are directly input to the front amplifiers 26 and 27 via the normal sound reproducing circuit. At this time, the sound output power switch 41 is turned on.

FIGS. 2 and 3 show a second embodiment of the present invention, in which an audio signal input switch 57, an audio signal output switch 59, a video signal input switch 65, and a video signal output switch 66 are all connected. No OFF terminal 5
A, 5B, 5C, 5D, and the switch units 4A, 4B,
4C and 4D have an off operation position. Further, the main power transformer 35 is used only for sound output. That is,
The secondary winding of the main power transformer 35 is made single, and the surround processor 24, the front amplifiers 26 and 27, and the rear amplifiers 28 and 2 are connected via the rectifier circuit 72.
9 is supplied with direct current. Then, the main power switch 38
However, it also functions as the sound output power switch of the first embodiment.

Then, the standby power transformer 36
However, DC is supplied to the audio signal switching device 31 and the video signal switching device 33 via the rectifier circuit 75 in addition to the microcomputer 50. The main power switch 38 is interlocked with the internal / external output changeover switch 58, and is turned on during surround reproduction and turned off during normal sound reproduction using a TV monitor. When the AV amplifier is on standby, the main power switch 38 is turned off, and the audio signal input switch 57, the audio signal output switch 59,
Video signal input switch 65 and video signal output switch 6
The switch units 4A, 4B, 4C, and 4D of No. 6 are set to the off operation positions, and connected to the OFF terminals 5A, 5B, 5C, and 5D (related displays and the like are also turned off), and the AV amplifier is set to a standby state.

In the embodiment, the audio signal is output from the external audio signal output terminal to the TV monitor.
An audio signal may be output from an external audio signal output terminal to an external amplifier and speaker without using the amplifier and speaker of the TV monitor. Also, in the embodiment,
Although a BS tuner, an LD player, a VTR, and the like are used as electronic devices having an audio output circuit and a video output circuit, electronic devices other than those described above may be used.

[0038]

[Effect of the Invention] As described in detail above, according to the present invention,
If an external amplifier such as a TV monitor is connected to the audio signal output terminal for the external speaker, sound reproduction can be performed using an amplifier and a speaker of the TV monitor without using a surround amplifier having a built-in AV amplifier. At the same time, as described above, if an amplifier or the like of a TV monitor is connected to the external audio signal output terminal, the surround playback and the use of the amplifier and speaker of the TV monitor can be performed simply by operating the internal / external output switch. Normal sound reproduction can be selected. Further, in the above case, power supply to the surround processor and the surround amplifier of the AV amplifier can be stopped, so that power can be saved, and the speakers connected to the surround amplifier are inadvertently driven, and the surround speakers may output sound. Nor.

In the case where the surround processor or surround amplifier of the AV amplifier is not used, such as when dubbing using an AV device, or when performing timer recording at the time of absence or at midnight, the surround sound is used. Since power supply to the processor and the surround amplifier can be stopped, power can also be saved in this case. Furthermore, according to the second aspect, since the inside / outside output changeover switch and the sound output power switch are linked, there is no need to separately operate the sound output power switch after the inside / outside output changeover switch is operated, which is convenient. It is.

[Brief description of the drawings]

FIG. 1 is a circuit diagram of an audio-visual system showing a first embodiment of the present invention.

FIG. 2 is a partial circuit diagram showing a second embodiment of the present invention.

FIG. 3 is a partial circuit diagram showing a second embodiment of the present invention.

FIG. 4 is a circuit diagram of an audio-visual system showing an example of the related art.

[Sign]

1. Audio visual amplifier (AV amplifier) 2.
... satellite broadcast tuner (BS tuner), 3 ... laser disk player (LD player), 4 ... video tape recorder (VTR), 5 ... television monitor (T
V monitor), 5A: amplifier, 5B: speaker, 6, 7
... front speakers (surround speakers), 8, 9 ...
Rear speaker (surround speaker), 20: external audio signal output terminal, 22: TV video signal output terminal, 24
... Surround processor, 26,27 ... Front amplifier (surround amplifier), 28,29 ... Rear amplifier (surround amplifier), 31 ... Sound signal switching device, 33
... video signal switching device, 35 ... main power transformer, 36
... power transformer for standby, 38 ... main power switch, 39 ... main power button, 41 ... sound output power switch, 42 ... sound output power button, 44 ... input selector, 46 ... surround mode selector, 48 ... timer recording setting device, 50: microcomputer, 57: sound signal input switch, 58: inside / outside output changeover switch, 59
... Acoustic signal output switch, 65 ... Video signal input switch, 66 ... Video signal output switch.

Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) G11B 31/00 G11B 20/00 H04S 1/00-7/00

Claims (2)

(57) [Scope of request for utility model registration] An audio signal input terminal and a video signal input terminal to which a plurality of audio signals and video signals are input from a plurality of audiovisual devices having an audio signal output circuit and a video signal output circuit, A surround processor capable of processing a sound signal and outputting a surround signal, interposed between a plurality of sound signal input terminals and the surround processor, and connecting the surround signal with the sound signal input terminal selected by the input selector. An audio signal input switch, a surround amplifier connected to a surround processor to drive a surround speaker, a video signal output terminal for a TV for outputting a video signal to a TV monitor, a plurality of video signal input terminals and a video signal output for a TV Video signal input that is interposed between terminals and selected by the input selector Video signal input switch for connecting the video signal output terminal for TV and the video signal input terminal, control means for controlling the audio signal input switch and the video signal input switch, power supply circuit for supplying power to the surround processor and the surround amplifier, and power supply to the control means An audio signal output terminal for outputting an audio signal to an external speaker via an external amplifier, an output side of an audio signal input switch, a surround processor and an audio signal for an external speaker. Interposed between the output terminals, controlled by the control means, regardless of the presence or absence of the connection of the external amplifier to the external speaker audio signal output terminal,
An internal / external output switch that can selectively connect the output side of the audio signal input switch to one of a surround processor and an external speaker audio signal output terminal; and an audio output power switch that opens and closes a power circuit of the surround processor and the surround amplifier. An audio-visual amplifier characterized by having 2. An audio output power switch when an output side of an audio signal input switch and an external audio signal output terminal are connected by an internal output switch and an audio output power switch. 2. The audio-visual amplifier according to claim 1, wherein the switch is turned off.