JPH11331996

Patent Translate
Powered by EPO and Google
Notice
This translation is machine-generated. It cannot be guaranteed that it is intelligible, accurate,
complete, reliable or fit for specific purposes. Critical decisions, such as commercially relevant or
financial decisions, should not be based on machine-translation output.
DESCRIPTION JPH11331996
[0001]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an
audio apparatus, and more particularly to an audio apparatus capable of driving a front speaker
of A system and a front speaker of B system.
[0002]
2. Description of the Related Art A speaker system on the front side is provided in two systems,
system A and system B. Normally, only system A reproduces sound (system A mode), and when it
is desired to change the sound field, switch to system (A + B) (system (A + B) System Mode) There
is a sound reproduction system designed to reproduce sound from both the A system and the B
system.
[0003]
FIG. 5 is a circuit diagram showing an example of a surround audio reproduction system capable
of switching between reproduction in the A system mode and reproduction in the (A + B) system
mode.
The Lch and Rch surround analog audio signals LT and RT input from a predetermined audio
source are converted into digital audio signals LT (D) and RT (D) by the A / D converter 1, and
Digital stereo signal processing FL (D), FR (D) for reproducing the surround sound field, and
10-05-2019
1
digital stereo rear audio signal RL (RD), RR (D (digital signal processor) 2) Is output. FL (FD) and
FR (FD) are D / A converted by the D / A converter 3 and analog stereo front audio signals FL (A)
and FR (A) from the first output terminals L1 and R1 to Lch and Rch Are output, and Lch and Rch
analog stereo rear audio signals RL (A), RR (A) are output from the second output terminals L2,
R2.
[0004]
The FL (A) and FR (A) output from the first output terminals L1 and R1 of the D / A converter 3
pass through the anti-aliasing filters 4L and 4R and the first volume adjustment circuits 5L and
5R, and the front power amplifier After being input to 6L and 6R and amplified in power, they
are input to the front speakers 8L and 8R of A system through relay switches 7L, 7R, front
speaker output terminals SPFL (A) and SPFR (A) of A system. . In addition, RL (A) and RR (A)
output from the second output terminals L2 and R2 of the D / A converter 3 pass through the
anti-aliasing filters 9L and 9R and the second volume control circuits 10L and 10R, respectively,
and the rear After being input to the power amplifiers 11L and 11R and amplified in power, they
are input to the rear speakers 13L and 13R through the relay switches 12L and 12R and the rear
speaker output terminals SPRL and SPRR. Further, the outputs of the front power amplifiers 6L
and 6R are input to the front speakers 15L and 15R of the B system through relay switches 14L
and 14R and the front speaker output terminals SPFL (B) and SPFR (B) of the B system.
[0005]
In the surround audio reproduction system configured as described above, when the user is
switching to the OFF position on the operation panel 16 for switching the speaker output system,
the controller 17 of the microcomputer configuration has relay switches 7L, 7R, 12L, 12R, Both
14L and 14R are in the open state, and both speaker outputs are off. When the user performs the
switching operation to the A position on the operation panel 16, the controller 17 closes the
relay switches 7L, 7R and 12L, 12R and leaves 14L, 14R open. As a result, the front speakers 8L
and 8R are driven by the outputs of the front power amplifiers 6L and 6R, and the rear speakers
13L and 13R are driven by the rear power amplifiers 11L and 11R, whereby a normal surround
sound field is realized.
[0006]
10-05-2019
2
Unlike this, when the user performs switching operation to the (A + B) position on the operation
panel 16, the controller 17 closes all of the relay switches 7L, 7R and 12L, 12R and 14L, 14R. As
a result, since both the front speakers 8L and 8R of system A and the front speakers 15L and
15R of system B are driven by the outputs of the front power amplifiers 6L and 6R, the sense of
expansion of the sound on the front side is increased, and the sound field is also increased.
Become richer.
[0007]
When the surround audio reproduction system of FIG. 5 can switch to the B system mode, when
the user performs the switching operation to the B position on the operation panel 16, the
controller 17 closes the relay switches 12L, 12R and 14L, 14R. Let 7L and 7R open. As a result,
the front speakers 15L and 15R of the B system are driven by the outputs of the front power
amplifiers 6L and 6R, and the rear speakers 13L and 13R are driven by the rear power amplifiers
11L and 11R, and surround sound using the front speakers of the B system. A place is realized.
[0008]
However, in the above-described conventional surround audio reproduction system, when
reproducing with the (A + B) system, two sets of the front speakers 8L, 8R and 15L, 15R of the A
system and the B system are all generated. Since the front power amplifiers 6L, 6R are driven by
one set of front power amplifiers, the load on the front power amplifiers 6L, 6R becomes heavy,
and there is a problem that the sound quality is deteriorated such that the distortion becomes
large. In addition, since a large current flows through the final power transistors of the front
power amplifiers 6L and 6R and the temperature rise is also large, a large-capacitance final
power transistor and a radiator are required, which causes a large burden on the configuration
and cost. There was also the problem of increasing.
[0009]
In addition, when performing reproduction only in the A system and reproduction in only the B
system, both of the Aronag stereo front audio signals are amplified by the front power amplifiers
6L and 6R, and the A system front speakers 8L, 8R or B systems are amplified. In order to drive
the front speakers 15L and 15R, a combination of the front speakers 15L and 15R of the B
system and the front power amplifiers 6L and 6R may not provide a good overall sound field
10-05-2019
3
characteristic. An object of the present invention is to provide an audio apparatus capable of
good sound reproduction in view of the problems of the prior art described above.
[0010]
According to a first aspect of the present invention, there is provided an audio apparatus
comprising: a first power amplifier for power amplifying a front audio signal; a second power
amplifier for power amplifying a rear audio signal; In an audio apparatus comprising a speaker
output terminal, a B system front speaker output terminal, and a rear speaker output terminal, an
input selection circuit is provided on the input side of a first power amplifier and a second power
amplifier, and a first power amplifier When the output selection circuit is provided on the output
side of the second power amplifier and the A channel is reproduced, the input selection circuit
outputs the front audio signal to the first power amplifier and the rear audio signal to the second
power amplifier, The output selection circuit outputs the output of the first power amplifier to
the A system front speaker output terminal and When the output of the two power amplifiers is
output to the rear speaker output terminal and the (A + B) system is reproduced, the input
selection circuit outputs the front audio signal to the first power amplifier and the second power
amplifier, and the output selection circuit It is characterized in that the output of the one power
amplifier is output to the A system front speaker output terminal and the output of the second
power amplifier is output to the B system front speaker output terminal.
[0011]
By this, when the reproduction of the A system is performed, the front audio signal is amplified
by the first power amplifier, and then the front speaker of the A system is driven, and the rear
audio signal is amplified by the second power amplifier. By driving the speakers, it is possible to
realize a surround sound field.
On the other hand, when the (A + B) system is reproduced, the front audio signal is amplified by
the first power amplifier and then the A system front speaker is driven, and the front audio signal
is amplified by the second power amplifier. Furthermore, by driving the front speakers of the B
system, reproduction of the (A + B) system becomes possible without putting a load on the first
power amplifier and the second power amplifier, and generation of distortion is avoided to
prevent deterioration of the sound quality. By suppressing the flow of a large current in the first
power amplifier and the second power amplifier, it is possible to avoid the use of a largecapacitance final-stage transistor or a radiator.
10-05-2019
4
[0012]
In the audio apparatus according to claim 2 of the present invention, in the apparatus according
to claim 1, the input selection circuit outputs the front audio signal to the first power amplifier
and the rear audio signal is the second power amplifier when performing reproduction of the B
system. And the output selection circuit outputs the output of the first power amplifier to the B
system front speaker output terminal and the output of the second power amplifier to the rear
speaker output terminal, or the input selection circuit outputs the front audio signal. And the rear
audio signal to the first power amplifier, and the output selection circuit outputs the output of
the second power amplifier to the B system front speaker output terminal and the output of the
first power amplifier It is characterized in that output is made to the speaker output terminal.
[0013]
Thereby, when performing reproduction of the B system, the front audio signal is amplified by
the first power amplifier, then the front speaker of the B system is driven, and the rear audio
signal is amplified by the second power amplifier, and then rear The speaker is driven or the
front audio signal is amplified by the second power amplifier and then the front speaker of
system B is driven, and the rear audio signal is amplified by the first power amplifier and then
the rear speaker is driven. Thus, it becomes possible to reproduce the B system without
burdening the first power amplifier and the second power amplifier, to avoid the occurrence of
distortion and to prevent the deterioration of the sound quality, or to the first power amplifier
and the second power amplifier. By suppressing the flow of a large current, it is possible to avoid
the use of a large capacity final-stage transistor or a heat sink.
In particular, when the total sound field characteristic combining the first power amplifier and
the A system front speaker is good and the total sound field characteristic combining the second
power amplifier and the B system front speaker is good, the A system is reproduced. When
performing reproduction of the B system at any time, good overall sound field characteristics can
be realized.
[0014]
In the audio apparatus according to the present invention, the first power amplifier for power
amplifying the front audio signal, the second power amplifier for power amplifying the rear audio
signal, the A system front speaker output terminal, and the B system front speaker output
terminal In an audio apparatus having a rear speaker output terminal, an input selection circuit is
provided on the input side of the first power amplifier and the second power amplifier, and an
output selection circuit on the output side of the first power amplifier and the second power
10-05-2019
5
amplifier. When the system A is to be reproduced, the input selection circuit outputs the front
audio signal to the first power amplifier and the rear audio signal to the second power amplifier,
and the output selection circuit outputs the output of the first power amplifier. The output of the
second power amplifier is output to the A system front speaker output terminal and When the
signal is output to the power output terminal and the B system is reproduced, the input selection
circuit outputs the front audio signal to the second power amplifier and the rear audio signal to
the first power amplifier, and the output selection circuit outputs the second power. It is
characterized in that the output of the amplifier is output to the B system front speaker output
terminal and the output of the first power amplifier is output to the rear speaker output terminal.
[0015]
By this, when the reproduction of the A system is performed, the front audio signal is amplified
by the first power amplifier, and then the front speaker of the A system is driven, and the rear
audio signal is amplified by the second power amplifier. When driving the speaker and
reproducing the B system, the power of the front audio signal is amplified by the second power
amplifier and then the front speaker of the B system is driven, and the rear audio signal is
amplified by the first power amplifier. Furthermore, by driving the rear speakers, a surround
sound field can be realized, and reproduction of B system is possible without putting a load on
the first power amplifier and the second power amplifier, and the occurrence of distortion is
avoided. To prevent the deterioration of the sound quality, to suppress the flow of a large current
to the first power amplifier, the second power amplifier, the end of the large capacity It is
possible to avoid the use of transistors and the radiator.
In particular, when the total sound field characteristic combining the first power amplifier and
the A system front speaker is good and the total sound field characteristic combining the second
power amplifier and the B system front speaker is good, the A system is reproduced. When
performing reproduction of the B system at any time, good overall sound field characteristics can
be realized.
[0016]
In the audio apparatus according to the present invention, the first volume adjustment circuit for
adjusting the volume of the front audio signal, the first power amplifier for amplifying the power
of the output of the first volume adjustment circuit, and the volume adjustment for the rear audio
signal An audio apparatus comprising a second volume control circuit, a second power amplifier
for power-amplifying the output of the second volume control circuit, an A system front speaker
10-05-2019
6
output terminal, a B system front speaker output terminal, and a rear speaker output terminal In
the above, when the input selection circuit is provided on the input side of the first volume
adjustment circuit and the second volume adjustment circuit, and the output selection circuit is
provided on the output side of the first power amplifier and the second power amplifier, The
input selection circuit outputs the front audio signal to the first volume control circuit and the
rear audio signal to the second volume control circuit. The output selection circuit outputs the
output of the first power amplifier to the A system front speaker output terminal and the output
of the second power amplifier to the rear speaker output terminal, and when the (A + B) system is
reproduced, the input selection circuit The front audio signal is output to the first volume
adjustment circuit and the second volume adjustment circuit, and the output selection circuit
outputs the output of the first power amplifier to the A system front speaker output terminal and
the output of the second power amplifier as the B system front It is characterized in that output
is made to the speaker output terminal.
[0017]
By this, when the reproduction of the A system is performed, the front audio signal is amplified
by the first power amplifier, and then the front speaker of the A system is driven, and the rear
audio signal is amplified by the second power amplifier. By driving the speakers, it is possible to
realize a surround sound field.
Further, the volume on the front side and the rear side can be adjusted independently by the first
volume adjustment circuit and the second volume adjustment circuit. On the other hand, when
the (A + B) system is reproduced, the front audio signal is amplified by the first power amplifier
and then the A system front speaker is driven, and the front audio signal is amplified by the
second power amplifier. Furthermore, by driving the front speakers of the B system, reproduction
of the (A + B) system becomes possible without putting a load on the first power amplifier and
the second power amplifier, and generation of distortion is avoided to prevent deterioration of
the sound quality. By suppressing the flow of a large current in the first power amplifier and the
second power amplifier, it is possible to avoid the use of a large-capacitance final-stage transistor
or a radiator. Furthermore, the volume of the A system and the B system can be adjusted
independently by the first volume adjustment circuit and the second volume adjustment circuit.
[0018]
In the audio apparatus according to claim 5, in the apparatus according to claim 4, the input
selection circuit outputs the front audio signal to the first volume adjustment circuit and the rear
audio signal to the second volume when performing reproduction of the B system. The output
10-05-2019
7
selection circuit outputs the output of the first power amplifier to the B system front speaker
output terminal and outputs the output of the second power amplifier to the rear speaker output
terminal, or the input selection circuit The audio signal is output to the second volume
adjustment circuit and the rear audio signal is output to the first volume adjustment circuit, and
the output selection circuit outputs the output of the second power amplifier to the B system
front speaker output terminal and the first power amplifier The present invention is
characterized in that the output of is output to the rear speaker output terminal.
[0019]
Thereby, when performing reproduction of the B system, the front audio signal is amplified by
the first power amplifier, then the front speaker of the B system is driven, and the rear audio
signal is amplified by the second power amplifier, and then rear The speaker is driven or the
front audio signal is amplified by the second power amplifier and then the front speaker of
system B is driven, and the rear audio signal is amplified by the first power amplifier and then
the rear speaker is driven. This makes it possible to realize a surround sound field, and also
enables reproduction of B system without putting a load on the first power amplifier and the
second power amplifier, and prevents the occurrence of distortion and prevents the deterioration
of the sound quality. , The second power amplifier, and a large-capacitance final-stage transistor
by suppressing the flow of a large current It is possible to avoid the use of the radiator.
Further, the volume on the front side and the rear side can be adjusted independently by the first
volume adjustment circuit and the second volume adjustment circuit. In particular, when the total
sound field characteristic combining the first power amplifier and the A system front speaker is
good and the total sound field characteristic combining the second power amplifier and the B
system front speaker is good, the A system is reproduced. When performing reproduction of the
B system at any time, good overall sound field characteristics can be realized.
[0020]
In the audio apparatus according to the present invention, the first volume adjustment circuit for
adjusting the volume of the front audio signal, the first power amplifier for power-amplifying the
output of the first volume adjustment circuit, and the volume adjustment for the rear audio signal
An audio apparatus comprising a second volume control circuit, a second power amplifier for
power-amplifying the output of the second volume control circuit, an A system front speaker
output terminal, a B system front speaker output terminal, and a rear speaker output terminal In
the above, when the input selection circuit is provided on the input side of the first volume
adjustment circuit and the second volume adjustment circuit, and the output selection circuit is
10-05-2019
8
provided on the output side of the first power amplifier and the second power amplifier, The
input selection circuit outputs the front audio signal to the first volume control circuit and the
rear audio signal to the second volume control circuit. The output selection circuit outputs the
output of the first power amplifier to the A system front speaker output terminal and the output
of the second power amplifier to the rear speaker output terminal, and when performing
reproduction of the B system, the input selection circuit is the front audio The signal is output to
the second volume adjustment circuit and the rear audio signal is output to the first volume
adjustment circuit, and the output selection circuit outputs the output of the second power
amplifier to the B system front speaker output terminal and the first power amplifier It is
characterized in that the output is outputted to the rear speaker output terminal.
[0021]
By this, when the reproduction of the A system is performed, the front audio signal is amplified
by the first power amplifier, and then the front speaker of the A system is driven, and the rear
audio signal is amplified by the second power amplifier. When driving the speaker and
reproducing the B system, the power of the front audio signal is amplified by the second power
amplifier and then the front speaker of the B system is driven, and the rear audio signal is
amplified by the first power amplifier. Furthermore, by driving the rear speakers, a surround
sound field can be realized, and reproduction of B system is possible without putting a load on
the first power amplifier and the second power amplifier, and the occurrence of distortion is
avoided. To prevent the deterioration of the sound quality, to suppress the flow of a large current
to the first power amplifier, the second power amplifier, the end of the large capacity It is
possible to avoid the use of transistors and the radiator.
Further, even in the case of reproducing any of the A system and the B system, the volume on the
front side and the rear side can be adjusted independently by the first volume adjustment circuit
and the second volume adjustment circuit. In particular, when the total sound field characteristic
combining the first power amplifier and the A system front speaker is good and the total sound
field characteristic combining the second power amplifier and the B system front speaker is
good, the A system is reproduced. When performing reproduction of the B system at any time,
good overall sound field characteristics can be realized.
[0022]
In the audio apparatus according to the present invention, the D / A converter for outputting the
analog front audio signal from the first output terminal and the analog rear audio signal from the
second output terminal, and the output of the analog front audio signal An audio apparatus
10-05-2019
9
comprising a first power amplifier for amplifying, a second power amplifier for power amplifying
an analog rear audio signal, an A system front speaker output terminal, a B system front speaker
output terminal, and a rear speaker output terminal The D / A converter can switch the operation
mode to the first mode and the second mode, and in the first operation mode, the analog front
audio signal from the first output terminal and the analog rear audio signal from the second
output terminal Output, and in the second operation mode, both the first output terminal and the
second output terminal The analog front audio signal is output, the output selection circuit is
provided on the output side of the first power amplifier and the second power amplifier, and the
D / A converter is set to the first operation mode when A system reproduction is performed.
When switching, the output selection circuit outputs the output of the first power amplifier to the
A system front speaker output terminal and outputs the output of the second power amplifier to
the rear speaker output terminal, and performs reproduction of the (A + B) system, The D / A
converter is switched to the second operation mode, the output selection circuit outputs the
output of the first power amplifier to the A system front speaker output terminal, and outputs the
output of the second power amplifier to the B system front speaker output terminal It is
characterized by having done so.
[0023]
By this, when the reproduction of the A system is performed, the front audio signal is amplified
by the first power amplifier, and then the front speaker of the A system is driven, and the rear
audio signal is amplified by the second power amplifier. By driving the speakers, it is possible to
realize a surround sound field.
On the other hand, when the (A + B) system is reproduced, the front audio signal is amplified by
the first power amplifier and then the A system front speaker is driven, and the front audio signal
is amplified by the second power amplifier. Furthermore, by driving the front speakers of the B
system, reproduction of the (A + B) system becomes possible without putting a load on the first
power amplifier and the second power amplifier, and generation of distortion is avoided to
prevent deterioration of the sound quality. By suppressing the flow of a large current in the first
power amplifier and the second power amplifier, it is possible to avoid the use of a largecapacitance final-stage transistor or a radiator.
[0024]
According to claim 8 of the present invention, in the apparatus according to claim 7, when
performing reproduction of B system, the D / A converter is switched to the first operation mode,
and the output selection circuit outputs the output of the first power amplifier. The output of the
10-05-2019
10
second power amplifier is output to the rear speaker output terminal, or the output of the second
power amplifier is output to the B system front speaker output terminal. It is characterized in
that the output is outputted to the rear speaker output terminal.
[0025]
Thereby, when performing reproduction of the B system, the front audio signal is amplified by
the first power amplifier, then the front speaker of the B system is driven, and the rear audio
signal is amplified by the second power amplifier, and then rear The speaker is driven or the
front audio signal is amplified by the second power amplifier and then the front speaker of
system B is driven, and the rear audio signal is amplified by the first power amplifier and then
the rear speaker is driven. This makes it possible to realize a surround sound field, and also
enables reproduction of B system without putting a load on the first power amplifier and the
second power amplifier, and prevents the occurrence of distortion and prevents the deterioration
of the sound quality. , The second power amplifier, and a large-capacitance final-stage transistor
by suppressing the flow of a large current It is possible to avoid the use of the radiator.
In particular, when the total sound field characteristic combining the first power amplifier and
the A system front speaker is good and the total sound field characteristic combining the second
power amplifier and the B system front speaker is good, the A system is reproduced. When
performing reproduction of the B system at any time, good overall sound field characteristics can
be realized.
[0026]
In the audio apparatus according to the present invention, the D / A converter which outputs the
analog front audio signal from the first output terminal and the analog rear audio signal from the
second output terminal, and the output of the analog front audio signal are powered. An audio
apparatus comprising a first power amplifier for amplifying, a second power amplifier for power
amplifying an analog rear audio signal, an A system front speaker output terminal, a B system
front speaker output terminal, and a rear speaker output terminal The D / A converter can switch
the operation mode to the first mode and the second mode, and in the first operation mode, the
analog front audio signal from the first output terminal and the analog rear audio signal from the
second output terminal Output, and in the second operation mode, from the second output
terminal When an analog rear audio signal is output from the first output terminal, an output
selection circuit is provided on the output side of the first power amplifier and the second power
amplifier, and D / A conversion is performed when A system reproduction is performed. Switch
to the first operation mode, the output selection circuit outputs the output of the first power
10-05-2019
11
amplifier to the A system front speaker output terminal, and outputs the output of the second
power amplifier to the rear speaker output terminal. When performing reproduction, the D / A
converter is switched to the second operation mode, the output selection circuit outputs the
output of the second power amplifier to the B system front speaker output terminal, and the
output of the first power amplifier is the rear speaker output terminal It is characterized in that it
outputs to.
[0027]
By this, when the reproduction of the A system is performed, the front audio signal is amplified
by the first power amplifier, and then the front speaker of the A system is driven, and the rear
audio signal is amplified by the second power amplifier. When driving the speaker and
reproducing the B system, the power of the front audio signal is amplified by the second power
amplifier and then the front speaker of the B system is driven, and the rear audio signal is
amplified by the first power amplifier. Furthermore, by driving the rear speakers, a surround
sound field can be realized, and reproduction of B system is possible without putting a load on
the first power amplifier and the second power amplifier, and the occurrence of distortion is
avoided. To prevent the deterioration of the sound quality, to suppress the flow of a large current
to the first power amplifier, the second power amplifier, the end of the large capacity It is
possible to avoid the use of transistors and the radiator.
In particular, when the total sound field characteristic combining the first power amplifier and
the A system front speaker is good and the total sound field characteristic combining the second
power amplifier and the B system front speaker is good, the A system is reproduced. When
performing reproduction of the B system at any time, good overall sound field characteristics can
be realized.
[0028]
BEST MODE FOR CARRYING OUT THE INVENTION A first embodiment of the present invention
will now be described with reference to FIG. FIG. 1 is a block diagram of a surround audio
reproduction system according to the present invention, and the same components as in FIG. 5
are assigned the same reference numerals. An input selection circuit 20 is interposed between
the output sides of the first volume adjustment circuits 5L and 5R and the second volume
adjustment circuits 10L and 10R and the input sides of the front power amplifiers 6L and 6R and
the rear power amplifiers 11L and 11R. It is done. In the input selection circuit 20, the output
10-05-2019
12
sides of the first volume adjustment circuits 5L and 5R are directly connected to the front power
amplifiers 6L and 6R.
[0029]
On the other hand, on the input side of the rear power amplifiers 11L and 11R, switching circuits
20L and 20R whose switching control is controlled by the controller 17A with a microcomputer
are provided, and the input side of the rear power amplifier 11L is a first volume adjustment
circuit. It can be switched between 5L and the second volume adjustment circuit 10L, and the
input side of the rear power amplifier 11R can be switched between the first volume adjustment
circuit 5R and the second volume adjustment circuit 10R. There is. The relay switches 14L and
14R connected to the B-system front speaker output terminals SPFL (B) and SPFR (B) are
connected to the rear power amplifiers 11L and 11R. An output selection circuit 30 is configured
by the relay switches 7L, 7R, 12L, 12R, 14L and 14R. The other components are the same as in
FIG.
[0030]
In the surround audio reproduction system configured as described above, when the user is
switching to the OFF position on the operation panel 16, the controller 17A selects one of the
relay switches 7L, 7R, 12L, 12R, 14L, 14R of the output selection circuit 30. Also, the speaker
output is turned off. When the user performs switching operation to the A position which is the A
system mode on the operation panel 16, the controller 17A switches the switching circuits 20L
and 20R of the input selection circuit 20 to the side of the second volume adjustment circuits
10L and 10R, and selects the output. The relay switches 7L, 7R and 12L, 12R of the circuit 30
are closed and 14L, 14R are left open.
[0031]
As a result, the front power amplifiers 6L and 6R power-amplify the analog stereo front audio
signals FL (A) 'and FR (A)' output from the first volume adjustment circuits 5L and 5R, and then
the A-system front speakers 8L. , Drive 8R. The rear power amplifiers 11L and 11R drive the rear
speakers 13L and 13R after power amplification of the analog stereo rear audio signals RL (A)
'and RR (A)' output from the second volume control circuits 10L and 10R. Do. As a result, a
surround sound field is realized, and the front and rear sides can be independently adjusted in
10-05-2019
13
volume by the first volume adjustment circuits 5L and 5R and the second volume adjustment
circuits 10L and 10R.
[0032]
Unlike this, when the user performs switching operation to the (A + B) position which is the (A +
B) system mode on the operation panel 16, the controller 17A switches the switching circuits
20L, 20R to the first volume adjustment circuits 5L, 5R side. The relay switches 7L, 7R and 14L,
14R are closed, and 12L, 12R are open.
[0033]
As a result, the front power amplifiers 6L and 6R power-amplify the analog stereo front audio
signals FL (A) 'and FR (A)' output from the first volume adjustment circuits 5L and 5R, and then
the A-system front speakers 8L. , Drive 8R.
The rear power amplifiers 11L and 11R also amplify the power of the analog stereo front audio
signals FL (A) 'and FR (A)' output from the first volume adjustment circuits 5L and 5R, and then
the front speakers 15L and 15R of the B system. Drive. As a result, reproduction in the (A + B)
system becomes possible, and the volume adjustment can also be performed by the first volume
adjustment circuits 5L and 5R.
[0034]
According to this embodiment, it is possible to reproduce the (A + B) system without burdening
the front power amplifiers 6L and 6R and the rear power amplifiers 11L and 11R, thereby
avoiding the occurrence of distortion and preventing the deterioration of the sound quality. In
each of the front power amplifiers 6L and 6R and the rear power amplifiers 11L and 11R, it is
possible to suppress the flow of a large current, and to avoid the use of a large-capacitance finalstage transistor or a radiator.
[0035]
Next, a second embodiment of the present invention will be described with reference to FIG.
10-05-2019
14
FIG. 2 is a block diagram of a surround audio reproduction system according to the present
invention, and the same components as in FIG. 1 are assigned the same reference numerals. An
input selection circuit 21 is interposed between the output sides of the anti-aliasing filters 4L, 4R,
9L and 9R and the input sides of the first volume adjustment circuits 5L and 5R and the second
volume adjustment circuits 10L and 10R. There is. In the input selection circuit 21, the output
sides of the anti-aliasing filters 4L and 4R are directly connected to the first volume adjustment
circuits 5L and 5R.
[0036]
On the other hand, on the input side of the second volume adjustment circuits 10L and 10R,
switching circuits 21L and 21R which are controlled to be switched by the controller 17B having
a microcomputer configuration are provided. The input side of the second volume adjustment
circuit 10L is Switching is possible between the aliasing filters 4L and 9L, and the input side of
the second volume adjustment circuit 10R can be switched between the anti-aliasing filters 4R
and 9R. The relay switches 14L and 14R connected to the B-system front speaker output
terminals SPFL (B) and SPFR (B) are connected to the rear power amplifiers 11L and 11R. An
output selection circuit 30 is configured by the relay switches 7L, 7R, 12L, 12R, 14L and 14R.
The other components are the same as in FIG.
[0037]
In the surround audio reproduction system configured as described above, when the user is
switching to the OFF position on the operation panel 16, the controller 17B selects one of the
relay switches 7L, 7R, 12L, 12R, 14L, 14R of the output selection circuit 30. Also, the speaker
output is turned off. When the user performs the switching operation to the A position on the
operation panel 16, the controller 17B switches the switching circuits 21L and 21R of the input
selection circuit 21 to the anti-aliasing filters 9L and 9R, and the relay switch 7L of the output
selection circuit 30. , 7R and 12L, 12R are closed and 14L, 14R are left open.
[0038]
As a result, the front power amplifiers 6L and 6R are output from the anti-aliasing filters 4L and
4R, and the analog stereo front audio signals FL (A) 'and FR (A) whose volumes are adjusted by
the first volume adjustment circuits 5L and 5R. After power amplification of ', the front speakers
10-05-2019
15
8L and 8R of A system are driven. The rear power amplifiers 11L and 11R are output from the
anti-aliasing filters 9L and 9R, and the analog stereo rear audio signals RL (A) 'and RR (A)' whose
volumes are adjusted by the second volume adjustment circuits 10L and 10R. Are amplified and
then the rear speakers 13L and 13R are driven. Thus, the surround sound field is realized, and
the volume adjustment can be performed independently on the front side and the rear side by
the first volume adjustment circuits 5L and 5R and the second volume adjustment circuits 10L
and 10R.
[0039]
Unlike this, when the user performs switching operation to the (A + B) position on the operation
panel 16, the controller 17B switches the switching circuits 21L and 21R of the input selection
circuit 21 to the side of the anti-aliasing filters 4L and 4R to select the output. The relay switches
7L, 7R and 14L, 14R of the circuit 30 are closed, and 12L, 12R are open.
[0040]
As a result, the front power amplifiers 6L and 6R are output from the anti-aliasing filters 4L and
4R, and the analog stereo front audio signals FL (A) 'and FR (A) whose volumes are adjusted by
the first volume adjustment circuits 5L and 5R. After power amplification of ', the front speakers
8L and 8R of A system are driven.
The rear power amplifiers 11L and 11R are output from the anti-aliasing filters 4L and 4R, and
the analog stereo front audio signals FL (A) * and FR (A) * whose volumes are adjusted by the
second volume adjustment circuits 10L and 10R. After power amplification and drive the front
speakers 15L and 15R of the B system. As a result, reproduction in the (A + B) system becomes
possible, and the A and B systems can be independently adjusted in volume by the first volume
adjustment circuits 5L and 5R and the second volume adjustment circuits 10L and 10R. .
[0041]
According to this embodiment, it is possible to reproduce the (A + B) system without burdening
the front power amplifiers 6L and 6R and the rear power amplifiers 11L and 11R, thereby
avoiding the occurrence of distortion and preventing the deterioration of the sound quality. In
each of the front power amplifiers 6L and 6R and the rear power amplifiers 11L and 11R, it is
possible to suppress the flow of a large current and to avoid the use of a large-capacitance final-
10-05-2019
16
stage transistor or a radiator. Further, it is possible to independently adjust the volume of the A
system and the B system by the first volume adjustment circuits 5L and 5R and the second
volume adjustment circuits 10L and 10R.
[0042]
Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 3
is a block diagram of a surround audio reproduction system according to the present invention,
and the same components as in FIG. 5 are assigned the same reference numerals. The D / A
converter 3C is capable of switching the operation mode to the first mode and the second mode
by the switching control of the controller 17C having a microcomputer configuration, and in the
first operation mode, the analog stereo from the first output terminals L1 and R1 Analog stereo
rear audio signals RL (A) and RR (A) are output from the front audio signals FL (A) and FR (A) and
the second output terminals L2 and R2, and in the second operation mode, the first output
terminal Analog stereo front audio signals FL (A) and FR (A) are output from both L1 and R1 and
the second output terminals L2 and R2.
[0043]
The relay switches 14L and 14R connected to the B-system front speaker output terminals SPFL
(B) and SPFR (B) are connected to the rear power amplifiers 11L and 11R. An output selection
circuit 30 is configured by the relay switches 7L, 7R, 12L, 12R, 14L and 14R. The other
components are the same as in FIG.
[0044]
In the surround audio reproduction system configured as described above, when the user is
switching to the OFF position on the operation panel 16, the controller 17C selects one of the
relay switches 7L, 7R, 12L, 12R, 14L, 14R of the output selection circuit 30. Also, the speaker
output is turned off. When the user performs the switching operation to the A position on the
operation panel 16, the controller 17C switches the operation mode of the D / A converter 3C to
the first mode, and the relay switches 7L, 7R and 12L, 12R of the output selection circuit 30 are
Close and leave 14L and 14R open.
10-05-2019
17
[0045]
As a result, the analog stereo front audio signals FL (A) and FR (A) output from the first output
terminals L1 and R1 of the D / A converter 3C are antialiasing filters in the front power
amplifiers 6L and 6R. The signals are input through the 4L and 4R and the first volume control
circuits 5L and 5R, and after power amplification, drive the front speakers 8L and 8R of the A
system. In addition, the analog stereo rear audio signals RL (A) and RR (A) output from the
second output terminals L2 and R2 of the D / A converter 3C are supplied to the rear power
amplifiers 11L and 11R, respectively, as the anti-aliasing filter 9L. , 9R, are input through the
second volume control circuits 10L and 10R, and drive the rear speakers 13L and 13R after
power amplification. As a result, a surround sound field is realized, and the front and rear sides
can be independently adjusted in volume by the first volume adjustment circuits 5L and 5R and
the second volume adjustment circuits 10L and 10R.
[0046]
Unlike this, when the user performs switching operation to the (A + B) position on the operation
panel, the controller 17C switches the operation mode of the D / A converter 3C to the second
mode, and the relay switches 7L and 7R of the output selection circuit 30. And 14L and 14R are
closed and 12L and 12R are open.
[0047]
As a result, the analog stereo front audio signals FL (A) and FR (A) output from the first output
terminals L1 and R1 of the D / A converter 3C are antialiasing filters in the front power
amplifiers 6L and 6R. The signals are input through the 4L and 4R and the first volume control
circuits 5L and 5R, and after power amplification, drive the front speakers 8L and 8R of the A
system.
In addition, the analog stereo front audio signals FL (A) and FR (A) output from the second output
terminals L2 and R2 of the D / A converter 3 are supplied to the rear power amplifiers 11L and
11R, respectively. , And 9R are input through the second volume control circuits 10L and 10R,
and after power amplification, drive the front speakers 13L and 13R of the B system. As a result,
reproduction in the (A + B) system becomes possible, and the volume adjustment can be
performed independently for the A and B systems by the first volume adjustment circuits 5L and
5R and the second volume adjustment circuits 10L and 10R.
10-05-2019
18
[0048]
According to this embodiment, it is possible to reproduce the (A + B) system without burdening
the front power amplifiers 6L and 6R and the rear power amplifiers 11L and 11R, thereby
avoiding the occurrence of distortion and preventing the deterioration of the sound quality. In
each of the front power amplifiers 6L and 6R and the rear power amplifiers 11L and 11R, it is
possible to suppress the flow of a large current, and to avoid the use of a large-capacitance finalstage transistor or a radiator. Further, it is not necessary to provide a special switching circuit,
and the volume control can be performed independently for the A and B systems by the first
volume control circuits 5L and 5R and the second volume control circuits 10L and 10R.
[0049]
The output selection circuit 30 'of the surround audio reproduction system of FIG. 1 is modified
as shown in FIG. 4, and the output sides of the front power amplifiers 6L and 6R and the front
speaker output terminals SPFL (B) of the B system and SPFR (B Also, relay switches 18L and 18R
are provided between them, and when the OFF position, the A position and the (A + B) position
are selected on the operation panel 16, the controller 17A keeps the relay switches 18L and 18R
open. The relay switch and the input selection circuit 20 are switched in the same manner as in
FIG. 1 according to the position.
[0050]
On the other hand, when the B position, which is the B system mode, is selected on the operation
panel 16, the controller 17A switches the switching circuits 20L and 20R of the input selection
circuit 20 to the side of the second volume adjustment circuits 10L and 10R, and the output
selection circuit By closing the relay switches 18L, 18R, 12L and 12R of 30 'and opening 7L and
7R, a surround sound field can be realized by the front speakers 15L and 15R of the B system
and the rear speakers 13L and 13R, A sound field different from the surround sound field by the
front speakers 8L and 8R of the A system and the rear speakers 13L and 13R can be realized.
At this time, the front power amplifiers 6L and 6R, and the rear power amplifiers 11L and 11R all
have only one speaker load connected, so no load is imposed, and the occurrence of distortion is
avoided to prevent the deterioration of the sound quality, and the front power It is possible to
prevent the use of a large-capacitance final-stage transistor or a radiator by suppressing a large
current from flowing to the amplifiers 6L, 6R and the rear power amplifiers 11L, 11R.
10-05-2019
19
[0051]
Also in the surround audio reproduction system of FIGS. 2 and 3, when the output selection
circuit is changed as shown in FIG. 4 and the OFF position, the A position, and the (A + B) position
are selected on the operation panel 16, the controller 17B (FIG. 2) Or 17C (FIG. 3) leave the relay
switches 18L and 18R open, and the other relay switches and the input selection circuit 21 (FIG.
2) or the D / A converter 3C (FIG. 3) Is switched in the same manner as in FIG. 2 or FIG. 3
depending on the position.
[0052]
On the other hand, when the B position which is the B system mode is selected on the operation
panel 16, the switching circuits 21L and 21R of the input selection circuit 21 are switched to the
antialiasing filters 9L and 9R, and the relay of the output selection circuit 30 ' By closing the
switches 18L, 18R, 12L and 12R and opening the 7L and 7R, a surround sound field can be
realized by the front speakers 15L and 15R of the B system and the rear speakers 13L and 13R.
A sound field different from the surround sound field by the speakers 8L and 8R and the rear
speakers 13L and 13R can be realized.
[0053]
Unlike this, in the surround audio reproduction system of FIG. 1, the input selection circuit 20
also has the input of the front power amplifier 6L on the input side of the front power amplifiers
6L and 6R as the output of the first volume adjustment circuit 5L and the second Switching
circuit (not shown) for switching between the outputs of the volume adjustment circuit 10L, and
switching for switching the input of the front power amplifier 6R between the output of the first
volume adjustment circuit 5R and the output of the second volume adjustment circuit 10R A
circuit (not shown) is added, and inputs of the front power amplifiers 6L and 6R are analog
stereo front audio signals FL (A) 'and FR (A)' and analog stereo rear audio signals RL (A) ', It is
possible to switch to RR (A) '.
[0054]
When the control panel 16 is switched to the OFF position, the A position, and the (A + B)
position, the controller 17A completely changes the output selection circuit 30 and the switching
circuits 20L and 20R of the input selection circuit 20 as in FIG. The same control is performed so
that the analog stereo front audio signals FL (A) 'and FR (A)' are input to the front power
amplifiers 6L and 6R.
10-05-2019
20
On the other hand, when switched to the B position, the relay switches 7L, 7R, 14L and 14R of
the output selection circuit 30 are closed, and in the input selection circuit 20, the analog stereo
rear audio signal RL (A) is supplied to the front power amplifiers 6L and 6R. ', RR (A)' are input,
and the analog stereo front audio signals FL (A) 'and FR (A)' are input to the rear power
amplifiers 11L and 11R, thereby the B system. A surround sound field can be realized by the
front speakers 15L and 15R and the front speakers 8L and 8R of the A system, and a sound field
different from the surround sound fields by the front speakers 8L and 8R of the A system and the
rear speakers 13L and 13R. Can be embodied.
[0055]
When playing back the B system, the front power amplifiers 6L and 6R and the rear power
amplifiers 11L and 11R all have only one speaker load connected, so there is no burden and
distortion is avoided to deteriorate the sound quality. It is possible to prevent large current from
flowing in the front power amplifiers 6L and 6R and the rear power amplifiers 11L and 11R, and
to avoid the use of a large-capacitance final-stage transistor or a radiator.
Also, the overall sound field characteristic combining the front power amplifiers 6L and 6R with
the front speakers 8L and 8R of the A system is good, and the total sound field combining the
rear power amplifiers 11L and 11R and the front speakers 15L and 15R of the B system When
the characteristics are good, good overall sound field characteristics can be realized when
performing reproduction of the A system and when performing reproduction of the B system.
[0056]
With regard to the surround audio reproduction system of FIG. 2 also, regarding the input
selection circuit 21, the input of the first volume adjustment circuit 5L is also the output of the
anti-aliasing filter 4L and the output of 9L on the input side of the first volume adjustment
circuits 5L and 5R. And a switching circuit (not shown) for switching the input of the first volume
adjustment circuit 5R between the output of the anti-aliasing filter 4R and the output of 9R. (1)
The inputs of the volume control circuits 5L and 5R can be switched between an analog stereo
front audio signal and an analog stereo rear audio signal.
[0057]
10-05-2019
21
When the operation panel 16 is switched to the OFF position, the A position, or the (A + B)
position, the system controller 17B operates on the output selection circuit 30 and the switching
circuits 21L and 21R of the input selection circuit 21 in the case of FIG. The same control is
performed so that analog stereo front audio signals are input to the first volume control circuits
5L and 5R.
On the other hand, when switched to the B position, the relay switches 7L, 7R, 14L, 14R of the
output selection circuit 30 are closed, and in the input selection circuit 21, the analog stereo rear
audio signal is input to the first volume adjustment circuits 5L, 5R. And the analog stereo front
audio signal is input to the second volume control circuits 10L and 10R, so that surround by the
front speakers 15L and 15R of the B system and the front speakers 8L and 8R of the A system. A
sound field can be realized, and a sound field different from the surround sound field by the front
speakers 8L and 8R of the A system and the rear speakers 13L and 13R can be realized.
[0058]
With regard to the surround audio reproduction system of FIG. 3 also, with regard to the D / A
converter 3C, in addition to the operation modes described above in the first mode and the
second mode, the analog stereo rear audio signal RL (A (A) from the first output terminals L1 and
R1 , RR (A), and can be switched to a third mode in which analog stereo front audio signals FL (A)
and FR (A) are output from the second output terminals L2 and R2.
[0059]
When the control panel 16 is switched to the OFF position, the A position, and the (A + B)
position, the system controller 17C performs the same control as in the case of FIG. 3 for the
output selection circuit 30 and for the D / A converter 3C. On the other hand, when switched to
the B position, the relay switches 7L, 7R, 14L and 14R of the output selection circuit 30 are
closed, 12L and 12R are opened, the D / A converter 3C is switched to the third mode, and the
front power The analog stereo rear audio signal is input to the amplifiers 6L and 6R, and the
analog stereo front audio signal is input to the rear power amplifiers 11L and 11R, whereby the
B-system front speakers 15L and 15R and Surround sound field by front speakers 8L and 8R of A
system Realization is possible, the front speakers 8L of system A, 8R and rear speakers 13L, 13R
can be implemented different sound field from the surround sound field by.
[0060]
10-05-2019
22
According to the present invention, it becomes possible to reproduce the (A + B) system without
burdening the first power amplifier and the second power amplifier, thereby avoiding the
occurrence of distortion and preventing the deterioration of the sound quality. It is possible to
suppress the flow of a large current in the first power amplifier and the second power amplifier,
and to avoid the use of a large-capacitance final-stage transistor or a radiator.
In addition, if the total sound field characteristic combining the first power amplifier and the A
system front speaker is good and the total sound field characteristic combining the second power
amplifier and the B system front speaker is good, the A system is reproduced. When performing
reproduction of the B system at any time, good overall sound field characteristics can be realized.
10-05-2019
23