JP2012049634A - Volume control system and sounding system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily control the volume of a sound emitted by a sounding apparatus to a volume comfortably audible to a user at the generation of noise.SOLUTION: In a TV system 10, a sound emitted by a television 20 (sounding apparatus) is measured just near the television 20, and a mixed sound in which the sound emitted by the television 20 is mixed with noise is measured by a remote control 100. A volume balance between the sound emitted by the television 20 and the noise in the position of the remote control 100 is controlled to a standard balance in accordance with the sound emitted by the television 20 and the mixed sound.

Description

  The present invention relates to a volume control system that adjusts the volume of sound produced by a sound generation device such as a television, a radio, an audio device, and the like, and a sound generation system having such an adjustment function.

  Sound generation systems in which the volume of sound generation devices such as televisions, radios, audio devices and the like are adjusted by a remote controller (remote controller) are widely used (see, for example, Patent Documents 1 to 4). In such a sound generation system, when noise occurs in the surroundings during viewing, the user increases the volume to a level that is easy to hear by appropriately operating the remote controller, and if the noise decreases, the volume is also reduced to a level that is not frustrating. It will be. However, there are not a few users who feel troublesome in such operations.

JP 05-11089 A JP-A-10-066185 JP 2003-304590 A JP 2008-053986 A

  Conventionally, there has been proposed a technique for eliminating noise itself, for example, canceling noise using a sound whose phase is reversed from that of noise. However, such a technique for eliminating the noise itself is not necessarily effective for large noise such as noise caused by trains and trucks, and housework such as cooking and dish washing. For this reason, even if a technique for eliminating the noise itself is used, if such a large noise occurs, it is highly likely that the user will eventually have to adjust the volume by operating the remote controller himself. .

  In view of the above circumstances, it is an object of the present invention to provide a volume adjustment system and a sound generation system that can easily adjust the sound volume produced by the sound generation device to a volume that is easy for the user to hear when noise occurs. is there.

  A volume control system that achieves the above object includes an observation device and a control device.

  The observation apparatus has a voice observation unit and a voice transmission unit.

  The voice observation unit observes a first voice emitted by a sounding device that emits a voice based on a voice signal at a volume adjusted by an instruction via a communication medium.

  The voice transmission unit transmits the first voice obtained by the observation of the voice observation unit via a communication medium.

  The adjusting device has an audio measuring unit, an audio receiving unit, and a volume adjusting unit.

  The sound measurement unit measures mixed sound in which the first sound emitted from the sounding device and the second sound from a source other than the sounding device are mixed.

  The voice receiving unit receives the first voice transmitted from the voice transmitting unit.

  The volume control unit gives instructions to the sounding device based on the first sound received by the sound receiving unit and the mixed sound measured by the sound measuring unit via a communication medium, and thereby the sounding device emits Adjust the audio volume as follows. That is, the volume control unit adjusts the volume of the sound produced by the sound generation device so that the volume balance between the first sound and the second sound in the mixed sound after the instruction approaches a predetermined reference balance. .

  The sound generation system that achieves the above object includes the sound generation device, the observation device, and the adjustment device.

  According to this case, when noise occurs, it is possible to easily adjust the volume of the sound produced by the sounding device to a volume that is easy for the user to listen to.

It is a schematic diagram which shows 1st Embodiment of a volume control system and a sound generation system. It is a schematic diagram which shows the television system (TV system) which is 2nd Embodiment of a volume control system and a sound generation system. It is a figure which shows typically the waveform of the audio | voice in the position where the remote control shown in FIG. 2 was placed. FIG. 3 is a diagram illustrating a hardware configuration of each of a remote controller and an observation device illustrated in FIG. 2. FIG. 3 is a functional block diagram showing the volume control system shown in FIG. 2 while paying attention to an automatic volume control function for the television 20. It is a flowchart which shows the flow of a coefficient determination process. It is a flowchart which shows the flow of a range determination process. It is a flowchart which shows the flow of a lower limit determination process. It is a flowchart which shows the flow of a process of automatic volume control. It is the graph which showed the change of SN ratio by the process of automatic volume control.

  Hereinafter, specific embodiments of the volume control system and the sound generation system of the present case will be described with reference to the drawings.

  FIG. 1 is a schematic diagram showing a first embodiment of a volume control system and a sound generation system.

  The sound generation system 1 shown in FIG. 1 includes a sound generation device 2, an observation device 1A, and an adjustment device 1B. A combination of the observation apparatus 1A and the adjustment apparatus 1B corresponds to an embodiment of the volume adjustment system of the present case.

  The sound producing device 2 emits sound based on the sound signal at a volume adjusted by an instruction via the communication medium.

  The observation apparatus 1A includes a voice observation unit 1A_1 and a voice transmission unit 1A_2.

  The sound observation unit 1A_1 observes the first sound emitted from the sound producing device 2.

  The observation here means that the sound emitted from the sound producing device 2 is monitored. This observation may be to measure the sound produced by the sounding device 2 itself. Alternatively, this observation may be, for example, measuring an audio signal that is input to a speaker in the sound generator 2 and that reflects the volume adjustment via the communication medium.

  The voice transmission unit 1A_2 transmits the first voice obtained by the observation of the voice observation unit 1A_1 via a communication medium.

  The adjusting device 1B includes an audio measuring unit 1B_1, an audio receiving unit 1B_2, and a volume adjusting unit 1B_3.

  The sound measuring unit 1B_1 measures a mixed sound in which the first sound emitted from the sounding device 2 and the second sound from a source other than the sounding device 2 are mixed.

  The voice receiver 1B_2 receives the first voice transmitted from the voice transmitter 1A_2.

  The volume control unit 1B_3 instructs the sound generator 2 via the communication medium based on the first sound received by the sound receiving unit 1B_2 and the mixed sound measured by the sound measuring unit 1B_1. The volume of the sound produced by the sound generator 2 is adjusted as follows. That is, the volume control unit 1B_3 adjusts the volume so that the volume balance between the first voice and the second voice in the mixed voice after the instruction approaches a predetermined reference balance.

  In the sound generation system 1 of FIG. 1, the first sound emitted from the sound generation device 2 that is the volume adjustment target is observed. Further, a mixed sound of the first sound and a second sound from a source other than the sound generator 2, that is, a noise mixed with the first sound is measured. Then, based on the first sound and the mixed sound, the volume of the sound generated by the sound producing device 2 is adjusted so that the volume balance between the first sound and the second sound (noise) becomes a predetermined reference balance. Is done.

  According to the sound generation system 1, the user listens to the volume of the sound generated by the sound generation device 2 by using, for example, a volume balance that allows the user to easily hear the sound from the sound generation device 2 in a noisy environment as a reference balance. The volume can be adjusted easily.

  FIG. 2 is a schematic diagram showing a television system (TV system) which is a second embodiment of the volume control system and the sound generation system.

  The TV system 10 of FIG. 2 is arranged in the immediate vicinity of the television 20, a remote control 100 for instructing the television 20 wirelessly using infrared communication for channel selection, volume adjustment, and the like. And an observation device 200. The television 20 corresponds to an example of a sounding device that emits sound based on an audio signal at a volume adjusted by an instruction via a communication medium. A combination of the remote controller 100 and the observation apparatus 200 corresponds to an embodiment of the volume control system of the present case. In addition, the wireless instruction using infrared communication in the TV system 10 of FIG. 2 corresponds to an example of an instruction via a communication medium.

  In the present embodiment, the television 20 is illustrated as an example of the above-described sounding device. However, the sounding device is not limited to the television, and may be, for example, a radio, an audio device, a computer with a built-in speaker, or the like. good.

  The remote controller 100 has a built-in microphone as will be described in detail later. In the remote controller 100, the sound at the position where the remote controller 100 is placed is measured by the microphone. In many cases, the remote control 100 is placed near a user who views the television 20. Therefore, in the remote controller 100, when the noise N is generated, the mixed sound S + N obtained by combining the sound S of the television 20 that has propagated to the position of the remote controller 100 and the noise N is measured.

  FIG. 3 is a diagram schematically showing a mixed sound waveform at a position where the remote controller shown in FIG. 2 is placed.

  In part (A) of FIG. 3, the waveform of the mixed speech S + N when the noise N is small is indicated by a solid line. In part (B), the waveform of the mixed speech S + N when the noise N is large is indicated by a solid line. In both part (A) and part (B), the audio S of the television 20 included in the mixed audio S + N is indicated by a dotted line.

  When the noise N is small, the mixed sound S + N at the position of the remote controller 100 is not so different from the sound S of the television 20 as shown in Part (A). For this reason, the user near the remote controller 100 can listen to the sound S of the television 20 without worrying about the noise N. On the other hand, when the noise N is large, the mixed sound S + N is greatly distorted with respect to the sound S of the television 20 as shown in Part (B). As a result, it becomes difficult for the user to hear the sound S of the television 20.

  Here, the position where the observation apparatus 200 shown in FIG. 2 is arranged is in the immediate vicinity of the television 20 as described above. For this reason, at the position of the observation apparatus 200, even if there is a noise N in the surroundings, the sound S of the television 20 becomes relatively large relative to the noise N. Furthermore, the observation apparatus 200 has a built-in microphone having directivity. As a result, in this observation apparatus 200, the sound that can be regarded as the sound S of the television 20 is stably measured by arranging the microphone so that the directivity of the microphone faces the television 20 side.

  On the other hand, in the remote controller 100 placed at a position away from the television 20, the sound S of the television 20 that is attenuated due to propagation to the position of the remote controller 100 is measured. Further, the microphone built in the remote controller 100 is omnidirectional. For this reason, in the position of the remote controller 100, the ambient noise N may be so large that it cannot be ignored with respect to the sound S of the television 20. As a result, the remote controller 100 measures the mixed sound S + N of the sound S and noise N of the television 20 unlike the observation device 200 described above.

  In the TV system 10 of FIG. 2, the observation device 200 transmits the measurement result to the remote controller 100. Then, in the remote controller 100, the volume of the television 20 is adjusted based on the sound measurement result at the position of the remote controller 100 and the measurement result transmitted from the observation device 200.

  FIG. 4 is a diagram illustrating a hardware configuration of each of the remote controller and the observation apparatus illustrated in FIG.

  Part (A) of FIG. 4 shows the hardware configuration of the remote controller 100. Part (B) shows the hardware configuration of the observation apparatus 200.

  The remote controller 100 includes a control IC (Integrated Circuit) 101, a memory 102, operation buttons 103, a microphone 104, an A / D conversion circuit 105, a wireless communication device 106, and an infrared communication device 107.

  A control IC 101 controls the entire operation of the remote controller 100. The memory 102 stores various operation programs, parameters used when the programs are operated, and the like. The operation button 103 is pressed by the user when selecting the channel of the television 20 or adjusting the volume. The microphone 104 is omnidirectional, measures the sound around the microphone 104, that is, around the remote controller 100, and outputs an analog voltage signal corresponding to the measured sound. First, the A / D conversion circuit 105 converts the output signal of the microphone 104 into an analog value representing the amplitude of the voice waveform represented by the output signal, that is, an analog value representing the volume. Then, the A / D conversion circuit 105 converts an analog value representing the volume into a digital signal. The wireless communication device 106 performs wireless communication with the outside of the remote controller 100 by a data transfer method using Bluetooth (registered trademark). Infrared communication device 107 communicates with the outside of remote controller 100 using infrared rays.

  The remote controller 100 wirelessly performs channel selection instructions, volume adjustments, and the like to the television 20 in response to user button operations on the operation buttons 103. Further, as will be described later, the remote controller 100 automatically performs wireless volume adjustment using infrared communication with the television 20.

  As shown in part (B) of FIG. 4, the observation apparatus 200 includes a control IC 201, a microphone 202, an A / D conversion circuit 203, and a wireless communication device 204.

  The control IC 201 controls the entire operation of the observation apparatus 200. The microphone 202 has directivity, measures the sound from the direction of the directivity, and outputs an analog voltage signal corresponding to the volume of the measured sound. First, the A / D conversion circuit 203 converts the output signal of the microphone 202 into an analog value representing the amplitude of the voice waveform represented by the output signal, that is, an analog value representing the volume. Then, the A / D conversion circuit 203 converts an analog value representing the volume into a digital signal. The wireless communication device 204 performs wireless communication with the outside of the observation apparatus 200 by a data transfer method based on Bluetooth (registered trademark).

  While the power is turned on, the observation apparatus 200 measures sound with the microphone 202, converts the measurement result into a digital signal representing sound volume, and wirelessly transmits it as needed. This wirelessly transmitted signal is received by the wireless communication device 106 of the remote controller 100. As a result, the sound measured by the observation apparatus 200 is transmitted to the remote controller 100 in the form of volume. Then, the transmitted sound volume is used for automatic sound volume adjustment to the television 20 together with the sound volume measured by the microphone 104 of the remote controller 100.

  FIG. 5 is a functional block diagram showing the volume control system shown in FIG. 2 while paying attention to the automatic volume control function for the television 20.

  As shown in FIG. 5, the observation apparatus 200 includes a TV-side sound measurement unit 210 and an audio transmission unit 220 as functional blocks that bear an automatic volume control function.

  The observation apparatus 200 is disposed in the immediate vicinity of the television 20 so that the directivity of the microphone 202 faces the television 20 side.

  The TV-side sound measuring unit 210 measures the sound from the television 20 at any time at the position of the observation device 200 (closest to the television 20) and obtains a signal representing the volume. The TV-side sound measuring unit 210 is carried by the control IC 201, the microphone 202, and the A / D conversion circuit 203 shown in Part (B) of FIG. The TV-side sound measurement unit 210 corresponds to an example of a sound observation unit that observes the first sound emitted from the sound generation device.

  In the present embodiment, the sound emitted from the sound generator (television 20) is observed by measuring the sound with a microphone. However, this observation is not limited to voice measurement. The observation may be performed, for example, by measuring a sound signal that reflects the volume adjustment and is input to the speaker in the sound generator.

  The audio transmission unit 220 wirelessly transmits a signal representing the volume obtained by the TV side sound measurement unit 210 using a data transfer method based on Bluetooth (registered trademark). The voice transmission unit 220 is carried by the wireless communication device 204 shown in Part (B) of FIG. 4 as hardware. The voice transmission unit 220 corresponds to an example of a voice transmission unit that transmits the first voice obtained by observation of the voice observation unit via a communication medium. In addition, wireless transmission using the data transfer method based on Bluetooth (registered trademark) by the voice transmission unit 220 corresponds to an example of transmission via a communication medium.

  The observation apparatus 200 described above corresponds to an example of an observation apparatus having a voice observation unit and a voice transmission unit.

  As shown in FIG. 5, the remote control 100 includes a remote control side sound measurement unit 110, a sound reception unit 120, and a volume control unit 130 as functional blocks responsible for automatic volume adjustment.

  Further, the volume control unit 130 includes an operation volume control unit 131, a balance calculation unit 132, a storage unit 133, a range determination unit 134, a coefficient determination unit 135, a lower limit determination unit 136, and an automatic volume control unit 137.

  Among these functional blocks, those other than the storage unit 133 are constructed by the control IC 101 of the remote controller 100 shown in FIG. 4 operating according to an operation program (not shown) stored in the memory 102.

  The remote-control-side sound measuring unit 110 measures the sound around the remote control 100 as needed to obtain a signal representing the volume. As the hardware, the remote-control-side sound measuring unit 110 is responsible for the control IC 101, the microphone 104, and the A / D conversion circuit 105 shown in Part (A) of FIG. The remote-control-side sound measuring unit 110 corresponds to an example of a sound measuring unit that measures mixed sound in which the first sound emitted from the sounding device and the second sound from a source other than the sounding device are mixed.

  The sound receiving unit 120 receives the signal transmitted from the sound transmitting unit 220 of the observation apparatus 200 by a data transfer method using Bluetooth (registered trademark). The voice receiving unit 120 is carried by the wireless communication device 106 shown in Part (A) of FIG. 4 as hardware. The voice transmission unit 220 corresponds to an example of a voice reception unit that receives the first voice transmitted from the voice transmission unit.

  The volume control unit 130 wirelessly uses infrared communication with the television 20 based on the volume represented by the signal received by the audio reception unit 120 and the volume obtained by the remote-control-side sound measurement unit 110. Adjust the volume. As will be described later, the volume adjustment is performed so that the volume balance between the sound from the television 20 and the noise at the position of the remote controller 100 approaches a predetermined reference balance. As the hardware, the volume adjustment unit 130 is handled by the control IC 101, the memory 102, and the operation button 103 shown in Part (A) of FIG. This volume control unit 130 corresponds to an example of a volume control unit that adjusts the volume of sound produced by the sounding device by instructing the sounding device via a communication medium. Moreover, the wireless volume control using infrared communication by the volume control unit 130 corresponds to an example of volume control by instructing via a communication medium.

  As described above, the volume control unit 130 includes the operation volume control unit 131, the balance calculation unit 132, the storage unit 133, the range determination unit 134, the coefficient determination unit 135, the lower limit determination unit 136, and the automatic volume control unit 137. ing.

  In response to the user's operation, the operation volume adjusting unit 131 adjusts the volume of the sound generated by the television 20 wirelessly using infrared communication according to the operation. The operation volume control unit 131 basically functions when manually adjusting the volume, but determines a reference range (described later) used for automatic volume control in response to a user operation. Also works. The operation sound volume adjustment unit 131 is handled by the control IC 101, the operation button 103, and the infrared communication device 107 shown in Part (A) of FIG. 4 as hardware.

  The balance calculation unit 132 is a television for the sound at the position of the remote controller 100 based on the sound volume obtained by the remote control sound measuring unit 110 and the sound volume represented by the signal received by the sound receiving unit 120. The S / N ratio of 20 voices and noise is calculated every 3 seconds. The balance calculation unit 132 is handled by the control IC 101 shown in Part (A) of FIG. 4 as hardware. Details of the SN ratio calculation processing by the balance calculation unit 132 will be described later.

  The storage unit 133 stores a reference range, a target range, a coefficient, and a lower limit described below.

  The reference range is a range for the SN ratio. This range is a range including a reference balance, which will be described later, which is an S / N ratio when the user can easily hear the sound of the television 20. In the present embodiment, when the SN ratio calculated every 3 seconds by the balance calculation unit 132 exceeds the upper limit of this reference range, an increase in volume to the television 20 is instructed. Further, when the SN ratio falls below the lower limit of the range, the volume reduction to the television 20 is instructed. The upper limit of the reference range is an S / N ratio that a user near the remote control 100 is concerned about because the noise of the sound of the television 20 is too great. The lower limit of the reference range is an S / N ratio at which the sound of the television 20 feels too loud despite the quiet noise.

  The target range is a narrower range within the above-described reference range for the SN ratio. In the present embodiment, the television 20 is repeatedly instructed to increase or decrease the volume until the SN ratio calculated every 3 seconds by the balance calculator 132 falls within this target range.

  This target range is a range that is narrower than the above-mentioned reference range, including the reference balance, and is an S / N ratio range in which the user who is near the remote controller 100 can easily hear the sound of the television 20. The width of this target range is sufficiently narrow so that the change in the S / N ratio is hardly perceivable by the user within this target range.

  The coefficient is a coefficient representing the attenuation when the sound emitted from the television 20 propagates to the position of the remote controller 100. In the present embodiment, the sound volume of the most recent television 20 transmitted wirelessly from the observation device 200 is multiplied by this coefficient to calculate the SN ratio at the position of the remote controller 100 when calculating the SN ratio. Treated as audio volume.

  The lower limit is the lower limit of the volume at the position of the remote control 100. This lower limit is a limit volume that makes it difficult for a user near the remote control 100 to hear even if the volume of the television 20 is too low and there is no noise.

  As for these reference range, target range, coefficient, and lower limit, default values determined in advance at the time of design are stored in the storage unit 133 at the shipping stage. When an initial setting process described later is executed in response to a user operation, the reference range, target range, coefficient, and lower limit in the storage unit 133 are updated to values determined by the initial setting process. In this embodiment, the initial setting process can be performed any number of times, and the reference range, target range, coefficient, and lower limit in the storage unit 133 are updated each time the initial setting process is performed. The storage unit 133 is carried by the memory 102 shown in Part (A) of FIG. 4 as hardware.

  The range determination unit 134, the coefficient determination unit 135, and the lower limit determination unit 136 are blocks that function during the initial setting process. In the initial setting process, the operation volume adjusting unit 131 also functions as described above.

  The range determination unit 134 receives the user's operation via the operation volume adjustment unit 131 in the initial setting process, and determines the reference range and the target range. The coefficient determination unit 135 determines the above-described coefficient in response to a user operation via the operation volume adjustment unit 131 in the initial setting process. The lower limit determination unit 136 receives the user's operation via the operation volume adjustment unit 131 in the initial setting process and determines the lower limit. These three functional blocks are all handled by the control IC 101 shown in Part (A) of FIG. 4 as hardware.

  Hereinafter, the initial setting process will be described.

  In the present embodiment, the remote controller 100 includes, as the operation buttons 103, a volume adjustment button, an initial setting start button, a range determination button, a coefficient determination button, a lower limit determination button, and an automatic volume adjustment instruction button. The initial setting process starts when the user operates the initial setting start button.

  In this embodiment, in the initial setting process, a coefficient determination process for determining the coefficient, a lower limit determination process for determining the lower limit, and a range determination process for determining the reference range and the target range are performed. There are three processes. Then, it is assumed that these three processes are instructed together with the operation procedure of each process by the manual so as to be executed in the order of the coefficient determination process, the lower limit determination process, and the range determination process.

  FIG. 6 is a flowchart showing the flow of coefficient determination processing.

  In the coefficient determination process shown in this flowchart, first, the user operates the volume adjustment button according to a manual instruction to adjust the volume of the audio of the television 20 to be slightly higher (step S101). Then, when the volume reaches the desired volume, the user operates the coefficient determination button. Then, the coefficient determination unit 135 samples a predetermined number of the sound volume represented by the signal from the observation device 200 and the sound volume obtained at any time by the remote control sound measuring unit 110 (step 102).

  Next, the coefficient determination unit 135 obtains a coefficient by dividing the sampled average value of the volume on the remote control sounding unit 110 side by the average value of the volume on the observation device 200 side (step 103). Then, the coefficient determination unit 135 updates the coefficient stored in the storage unit 133 with the calculated coefficient (step S104). Thereafter, the coefficient determination process ends.

  The remote controller 100 is provided with an LED display (not shown) that notifies the user of the end of the process by lighting for each of the coefficient determination process, the lower limit determination process, and the range determination process. When the coefficient determination process described above is completed, the LED display unit for notifying the end of the coefficient determination process is turned on to notify the user to that effect, and subsequently the lower limit determination process is executed.

  FIG. 7 is a flowchart showing the flow of the lower limit determination process.

  As described above, the lower limit determined by the lower limit determination process is a limit volume that makes it difficult to hear even if the volume of the television 20 is too low and there is no noise.

  In the lower limit determination process shown in this flowchart, first, the user operates the volume adjustment button according to a manual instruction to adjust the volume of the audio of the television 20 to the lower limit volume at which the limit is felt as described above (step S201). . Then, when the volume reaches a desired volume, the user operates the lower limit determination button. Then, the lower limit determination unit 136 samples a predetermined volume of the sound volume represented by the signal from the observation device 200 at any time (step 202).

  Then, the lower limit determining unit 136 calculates the average value of the sampled volume on the remote control sounding unit 110 side as the lower limit, and updates the lower limit stored in the storage unit 133 to the calculated lower limit (step S203). . Thereafter, the lower limit determination process ends.

  When the lower limit determining process is completed, the LED display unit for notifying the lower limit determining process is turned on to notify the user to that effect, and then the range determining process is executed.

  FIG. 8 is a flowchart showing the flow of range determination processing.

  In the range determination process shown in this flowchart, first, the user operates the volume adjustment button according to a manual instruction to adjust the volume of the audio of the television 20 to a volume that is easy to listen to (step S301). Then, when the volume reaches the desired volume, the user operates the range determination button. Then, the range determination unit 134 samples a predetermined number of the sound volume represented by the signal from the observation device 200 and the sound volume obtained at any time by the remote-control-side sound measurement unit 110 (step 302).

  Subsequently, the range determination unit 134 calculates the SN ratio between the sound of the television 20 and noise at the position of the remote controller 100 as follows (step S303).

  The range determination unit 134 first multiplies the sampled average value of the volume on the observation device 200 side by the coefficient determined in the coefficient determination process and stored in the storage unit 133. In this embodiment, the result of this multiplication is handled as the volume of the audio of the television 20 at the position of the remote controller 100. Next, the range determination unit 134 subtracts the multiplication result from the sampled average sound volume on the remote control sounding unit 110 side. In the present embodiment, the result of this subtraction is treated as the noise volume at the position of the remote controller 100. Then, the range determination unit 134 obtains the SN ratio by dividing the subtraction result (noise volume) by the multiplication result (audio volume of the television 20). In the present embodiment, this SN ratio is calculated in decibel expression. The range determination unit 134 stores the calculated SN ratio in the memory 102 as a reference balance.

  Next, the range determination unit 134 uses a value obtained by adding 0.176 dB to the reference balance (reference balance +0.176 dB) and a value obtained by subtracting 0.176 dB from the reference balance (reference balance -0.176 dB) as a reference. Obtained as upper and lower limit values representing the range (step S304).

  Furthermore, the range determination unit 134 calculates a value obtained by adding 0.05 dB to the reference balance (reference balance + 0.05 dB) and a value obtained by subtracting 0.05 dB from the reference balance (reference balance−0.05 dB). Is obtained as upper and lower limit values (step S305).

  Then, the range determining unit 134 updates the reference range and target range stored in the storage unit 133 to the reference range and target range obtained as described above (step S306). Thereafter, the range determination process ends.

  When the range determining process is completed, the LED display unit for notifying the end of the range determining process is turned on to notify the user to that effect. The initial setting process ends with the end of the range determination process. The user recognizes that all the initial setting processes have been completed by observing that the LED display unit for notifying the end of the range determination process is lit.

  In this embodiment, automatic volume adjustment is started when the user operates an automatic volume adjustment instruction button. The user may start the automatic volume adjustment through execution of the initial setting process after the television 20 and the observation apparatus 200 are powered on. Alternatively, the automatic volume adjustment may be started by operating the automatic volume adjustment instruction button immediately after the power is turned on, omitting the initial setting process. When the initial setting process is omitted, in the automatic volume control, the default value or the setting value in the past initial setting process is used as it is.

  When the automatic volume adjustment is started after the execution of the initial setting process, the volume of the television 20 at the start of the automatic volume adjustment is adjusted by the range determination unit in step S301, and the user who is near the remote controller 100. The volume feels easy to hear.

  In addition, when the initial setting process is omitted, the volume of the television 20 at the time of starting the automatic volume adjustment is the adjusted volume when the volume is adjusted by a user operation after the power is turned on. When the automatic volume adjustment is started immediately after the power is turned on, the volume of the television 20 at the start of the automatic volume adjustment is the set volume at the time when the power is turned off last time.

  The automatic volume control is performed by calculation of the SN ratio every 3 seconds by the balance calculation unit 132 and the operation of the automatic volume control unit 137 described below.

  The automatic volume control unit 137 instructs the television 20 to increase or decrease the volume when the SN ratio calculated by the balance calculation unit 132 becomes a value outside the above reference range. This volume adjustment is basically continued until the SN ratio calculated by the balance calculation unit 132 falls within the target range. However, regarding the volume reduction instruction, the automatic volume adjustment unit 137 is performed so that the measurement result of the remote-control-side sound measurement unit 110 exceeds the lower limit. The automatic volume controller 137 is carried by the control IC 101 and the wireless communication device 106 shown in Part (A) of FIG. 4 as hardware.

  Hereinafter, the automatic volume control will be described with reference to flowcharts although there are some overlapping portions.

  FIG. 9 is a flowchart showing the flow of automatic volume control processing.

  When the automatic volume control process shown in this flowchart is started, the balance calculation unit 132 samples the volume represented by the signal from the observation device 200 and the volume required by the remote-control-side sound measurement unit 110 at intervals of 3 seconds. To do. Further, the balance calculation unit 132 calculates the SN ratio based on the volume for each sampling (step 401).

  In step 401, the balance calculation unit 132 first multiplies the sampled sound volume on the observation apparatus 200 side by the above coefficient to obtain the sound volume of the television 20 at the position of the remote controller 100. Furthermore, the balance calculation unit 132 subtracts the volume obtained by multiplying the coefficient as described above from the sampled sound volume on the remote control sounding unit 110 side to obtain the volume of noise at the position of the remote control 100. Then, the balance calculation unit 132 obtains the SN ratio by dividing the noise volume by the volume of the television 20 sound. The balance calculation unit 132 repeatedly executes processing from sampling to calculation of the SN ratio at intervals of 3 seconds.

  In the present embodiment, when the automatic volume adjustment instruction button is operated again by the user during execution of automatic volume adjustment, the process is interrupted at that time (step S402). Then, when this interruption is made (Yes determination in step S402), the automatic volume control processing is ended. On the other hand, unless such an interruption is made (No determination in step S402), the processing from the sampling to the calculation of the SN ratio is repeated by the balance calculation unit 132 at intervals of 3 seconds.

  Further, the S / N ratio calculated by the balance calculation unit 132 is compared with the reference range by the automatic volume control unit 137 (step S403).

  If the S / N ratio is within the reference range, the television 20 is not instructed to increase or decrease the volume, and the process returns to Step S403, and the comparison between the S / N ratio and the reference range is repeated.

  Then, for example, when a loud noise such as noise caused by trains or trucks or noise caused by housework such as cooking or dish washing occurs and the S / N ratio exceeds the upper limit of the reference range, the automatic volume control unit 137 causes the television 20 to Is given (step S404). That is, in step S404, the automatic volume controller 137 instructs the television 20 to increase the volume wirelessly using infrared communication. This instruction to increase the volume stops when the SN ratio calculated every 3 seconds becomes a value within the above target range. Then, after the stop, the process returns to step S403.

  On the other hand, when there is no noise and only the loud sound of the television 20 is left and the SN ratio falls below the lower limit of the reference range, the automatic volume control unit 137 reduces the volume of the television 20 by infrared communication. Is used to instruct wirelessly (step S405). The instruction to reduce the volume in step S405 is basically stopped when the SN ratio calculated every 3 seconds becomes a value within the above target range. However, when the sound volume measured at any time by the remote-control-side sound measuring unit 110 falls below the lower limit, the sound volume reduction instruction is stopped and the sound volume is increased even if the SN ratio is not yet within the target range. Instructed. This is a consideration for preventing the volume of the television 20 from being excessively lowered when there is almost no noise and the SN ratio is very small. The instruction to increase the sound volume at this time is stopped when the sound volume measured by the remote control sound measuring unit 110 exceeds the lower limit. As described above, when the instruction to decrease or increase the volume in step S405 is stopped, the process returns to step S403.

  According to the automatic volume adjustment process described above, when a large amount of noise is generated around the user during viewing of the television 20, the volume is automatically increased to a level that is easy for the user to hear. Also, if the noise disappears after the volume increase and the sound of the television 20 is too loud as it is, the volume is automatically reduced to a level that is easy to hear.

  FIG. 10 is a graph showing a change in the S / N ratio due to the automatic volume control process.

  In the graph G1 shown in FIG. 10, time is taken on the horizontal axis and the SN ratio is taken on the vertical axis, and the change in the SN ratio as a result of the automatic volume adjustment process is indicated by a broken line L1. The broken line L1 is obtained by connecting the S / N ratios calculated every 3 seconds by the balance calculation unit 132 with a solid line during the automatic volume control process. In the example of FIG. 10, the SN ratio is initially the above-described reference balance.

  Here, it is assumed that noise occurs due to the passage of a train. Noise increases as the train approaches, and as a result, the signal-to-noise ratio also increases. Then, when the SN ratio exceeds the upper limit of the reference range (reference balance +0, 176 dB), an instruction to increase the volume for the television 20 is started. As a result, the increase in the S / N ratio reaches its peak and eventually begins to decrease. This instruction to increase the volume is continued until the SN ratio falls below the upper limit (reference balance + 0.05 dB) of the target range.

  Next, when the train passes and the noise becomes small, the sound volume of the television 20 is too loud, and the SN ratio falls below the lower limit of the reference range (reference balance −0, 176 dB). Then, at that time, an instruction to reduce the volume with respect to the television 20 is started. As a result, the decrease in the SN ratio hits the bottom and eventually begins to increase. This instruction to decrease the sound volume is continued until the SN ratio exceeds the lower limit of the target range (reference balance −0.05 dB).

  However, when the volume of the sound measured by the remote control sound measuring unit 110 falls below the lower limit (for example, 40 dB), the instruction to reduce the volume is stopped even if the SN ratio does not exceed the lower limit of the target range. Volume increase is instructed until the ratio exceeds the lower limit.

  As described above, according to the automatic volume adjustment process of the present embodiment, the volume of the sound produced by the television 20 can be automatically adjusted to a volume that is easy for the user to hear when noise occurs. In addition, the reference range and the target range are calculated using, as a reference balance, the SN ratio when the volume of the television 20 is adjusted to a volume that is easy for the user to hear in the initial setting process. As a result, the reference range and target range used for automatic volume adjustment are in accordance with the user's sense of volume, and volume adjustment in accordance with the user's sense is possible. Further, the lower limit for preventing the volume of the television 20 from being lowered too much is determined at the user's desired level in the initial setting process, so that the volume can be adjusted in accordance with the user's sense for the lower limit. ing.

  Here, in the present embodiment, a manual volume adjustment function is also incorporated in the remote controller 100 having an automatic volume adjustment function. Since the remote controller 100 having such a manual volume control function has a high probability of being placed near the user during viewing, the remote controller 100 can measure the voice being listened to by the user with a high probability. This means that the following application forms are suitable for the volume control system of the present case.

  In this application mode, the volume control unit has an operation volume control unit. The operation volume adjusting unit adjusts the volume of the sound produced by the sounding device via a communication medium in accordance with a user operation.

  The operation volume adjustment unit 131 in the present embodiment corresponds to an example of the operation volume adjustment unit in the above-described application mode.

  In the present embodiment, the volume adjustment is performed when the volume balance (S / N ratio) between the sound and noise of the television 20 at the position of the remote controller 100 is out of the reference range. As a result, the volume adjustment is executed only when the user feels uncomfortable, and the processing efficiency is improved. This means that the following application forms are suitable for the volume control system of the present case.

  In this application mode, the volume control unit includes a balance calculation unit, a reference range storage unit, an adjustment unit, and an adjustment start unit. The balance calculation unit calculates the volume balance in the mixed sound based on the first sound received by the sound receiving unit and the mixed sound measured by the sound measuring unit. The reference range storage unit stores a reference range including the reference balance for the volume balance. The adjusting unit adjusts the volume of the sound produced by the sound generator so that the volume balance of the mixed sound approaches the reference balance. The adjustment start unit causes the adjustment unit to start adjusting the volume when the volume balance calculated by the balance calculation unit is out of the reference range.

  The balance calculation unit 132 in the present embodiment corresponds to an example of the balance calculation unit in this application mode. In addition, the storage unit 133 in the present embodiment corresponds to an example of a reference range storage unit in this application mode. Further, the automatic volume control unit 137 in the present embodiment corresponds to an example in which the adjustment unit and the adjustment start unit in this application mode are combined.

  In the present embodiment, the above S / N ratio is used as a volume balance between the sound of the television 20 and noise at the position of the remote controller 100. That is, in this embodiment, the ratio is used as an index indicating the volume balance, not the volume itself. This makes it possible to reliably adjust the volume of the television 20 to a volume that can be easily heard by the user in such a noise environment, regardless of the volume of the noise. This means that the following application form is more suitable for the above application form in which the volume adjustment unit has a balance calculation unit, a reference range storage unit, an adjustment unit, and an adjustment start unit. Yes.

  In this application mode, the balance calculation unit calculates a ratio between the volume of the second sound in the mixed sound and the volume of the first sound in the mixed sound as the volume balance.

  The balance calculation unit 132 in the present embodiment also corresponds to an example of the balance calculation unit in this application mode.

  Further, in the present embodiment, in the initial setting process, a coefficient representing the attenuation when the sound from the television 20 propagates to the position of the remote controller 100 is obtained. Then, the sound volume transmitted from the observation device 200 multiplied by the coefficient of the sound nearest to the television 20 is treated as the sound volume of the television 20 at the position of the remote controller 100. Thereby, the volume of the sound of the television 20 and the volume of the noise at the position of the remote controller 100 are obtained with high accuracy in consideration of the above-described attenuation. This means that the following application form is more suitable for the above application form in which the volume adjustment unit has a balance calculation unit, a reference range storage unit, an adjustment unit, and an adjustment start unit. Yes.

  In this application mode, the volume control unit includes a coefficient calculation unit and a coefficient storage unit. The coefficient calculation unit receives an operation for instructing the initial setting from the user, causes the sound measurement unit to measure the mixed sound at the time of the operation, and causes the volume reception unit to receive the first sound at the time of the operation. Then, the coefficient calculation unit calculates a coefficient obtained by dividing the measured volume of the mixed sound by the volume of the received first sound as an initial setting value. The coefficient storage unit stores the coefficient calculated by the coefficient calculation unit. Further, in this application mode, the balance calculation unit treats a volume obtained by multiplying the volume of the first sound received by the volume reception unit by the coefficient as the volume of the first sound in the mixed sound. The volume balance is calculated.

  The coefficient determination unit 135 in the present embodiment corresponds to an example of a coefficient calculation unit in this application mode. Further, the storage unit 133 in the present embodiment also corresponds to an example of a coefficient storage unit in this application mode. Further, the balance calculation unit 132 in the present embodiment also corresponds to an example of the balance calculation unit in this application mode.

  Further, in the present embodiment, the automatic volume controller 137 instructs the television 20 to increase or decrease the volume until the balance calculator 132 calculates the SN ratio within the target range. This target range is a narrow range including a reference balance predetermined in the initial setting process. Thereby, the volume of the television 20 can be precisely adjusted so as to approach this reference balance. This means that the following application form is more suitable for the above application form in which the volume adjustment unit has a balance calculation unit, a reference range storage unit, an adjustment unit, and an adjustment start unit. Yes.

  In this application mode, the volume control unit has a target range storage unit that stores a target range that includes the reference balance but is narrower than the reference range. In this application mode, the adjustment unit repeats the volume adjustment of the sound emitted by the sounding device until the balance calculation unit calculates the sound balance within the target range.

  The storage unit 133 in the present embodiment also corresponds to an example of a target range storage unit in this application mode. Further, the automatic volume control unit 137 in the present embodiment also corresponds to an example of the control unit in this application mode.

  In the present embodiment, the lower limit for the sound volume reduction instruction is determined in the initial setting process. Thereby, when there is almost no noise and the SN ratio is very small, the volume of the television 20 can be adjusted so as not to be lowered too much. This means that the following application form is more suitable for the above application form in which the volume adjustment unit has a balance calculation unit, a reference range storage unit, an adjustment unit, and an adjustment start unit. Yes.

  In this application mode, the volume control unit has a lower limit storage unit that stores a lower limit for the volume of the mixed voice measured by the voice measurement unit. In this application mode, the adjusting unit performs the following volume adjustment in preference to bringing the volume balance close to the reference balance. That is, the adjusting unit adjusts the volume of the sound produced by the sounding device so that the volume of the mixed sound measured by the sound measuring unit is equal to or higher than the lower limit.

  The storage unit 133 in the present embodiment also corresponds to an example of a lower limit storage unit in this application mode. The automatic volume control unit 137 in the present embodiment also corresponds to an example of the volume control unit in this applied mode.

  In this embodiment, as an example of an instruction via a communication medium or a transmission via a communication medium, an example of an instruction or transmission by wireless using a data transfer method by infrared communication or Bluetooth (registered trademark) is illustrated. . However, instructions via a communication medium and transmission via a communication medium are not limited to wireless instructions and transmission. The instruction via the communication medium or the transmission via the communication medium may be a wired instruction or transmission via the communication cable.

  In this embodiment, as an example of “wireless” communication, infrared communication and wireless communication using a Bluetooth (registered trademark) data transfer method are illustrated. However, “wireless” communication is not limited thereto. is not. The “wireless” communication may be, for example, wireless communication using a wireless LAN (Local Area Network), wireless communication using a wireless USB (Upper Side Band), or the like.

  In this embodiment, as an embodiment of the volume control system and the sound generation system of the present case, the form using the coefficient and the lower limit together with the reference range and the target range is illustrated, but the volume control system and the sound generation system of the present case are included in this. It is not limited. The volume control system and the sound generation system of the present case may be, for example, a form using only the above range, or may be a form using any one of a coefficient and a lower limit together with the above range.

  Further, in the present embodiment, as an embodiment of the volume control system and the sound generation system of the present case, a form in which the values in the storage unit are updated in response to a user operation in the initial setting process for the reference range, target range, coefficient, and lower limit. Illustrated. However, the volume control system and the sound generation system in this case are not limited to this. The volume control system and the sound generation system according to the present embodiment may be in a form in which, for example, the values obtained at the time of designing the system are stored as fixed values in the storage unit and used continuously for the above range, coefficient, and lower limit.

  Further, in the present embodiment, as an embodiment of the volume control system and the sound generation system of the present case, a mode in which the LED display unit is provided in the remote control for the end notification of each of the coefficient determination process, the lower limit determination process, and the range determination process is provided. Illustrated. However, the volume control system and the sound generation system in this case are not limited to this. The volume control system and the sound generation system of the present case may be, for example, one in which a small display screen on which a message for notifying the above-mentioned termination is displayed is provided on the remote control. Alternatively, the volume control system and the sound generation system of the present case may be one in which a television is instructed to display a message informing the end notification from a remote controller, and the message is displayed on the television screen.

  Hereinafter, the following additional notes will be disclosed regarding various forms of the volume control system and the sound generation system of the present case.

(Appendix 1)
A sound observing unit for observing a first sound emitted by a sounding device that emits sound based on a sound signal at a volume adjusted by an instruction via a communication medium;
An observation device having an audio transmission unit that transmits a first audio obtained by observation of the audio observation unit via a communication medium; and
A sound measuring unit that measures mixed sound in which the first sound emitted by the sounding device and the second sound from a source other than the sounding device are mixed;
An audio receiver for receiving the first audio transmitted from the audio transmitter;
By instructing the sounding device based on the first sound received by the sound receiving unit and the mixed sound measured by the sound measuring unit via a communication medium, the volume of the sound emitted by the sounding device is determined. A volume control unit that adjusts the volume balance between the first sound and the second sound in the mixed sound after the instruction so as to approach a predetermined reference balance;
A volume control system characterized by comprising:

(Appendix 2)
The volume control unit is
The volume control system according to supplementary note 1, further comprising an operation volume control unit that adjusts the volume of the sound produced by the sounding device via a communication medium in accordance with a user operation.

(Appendix 3)
The volume control unit is
A balance calculating unit that calculates the volume balance in the mixed sound based on the first sound received by the sound receiving unit and the mixed sound measured by the sound measuring unit;
For the volume balance, a reference range storage unit that stores a reference range including the reference balance;
An adjustment unit that adjusts the volume of the sound generated by the sound generation device so that the volume balance in the mixed sound approaches the reference balance;
The volume according to claim 1 or 2, further comprising: an adjustment start unit that causes the adjustment unit to start adjusting the volume when the volume balance calculated by the balance calculation unit is out of the reference range. Adjustment system.

(Appendix 4)
The supplementary note 3, wherein the balance calculating unit calculates a ratio between the volume of the second sound in the mixed sound and the volume of the first sound in the mixed sound as the volume balance. Volume control system.

(Appendix 5)
The volume control unit is
In response to an operation for instructing the initial setting from the user, the sound measurement unit measures the mixed sound at the time of the operation, and the volume receiving unit receives the first sound at the time of the operation, and the measured mixed sound A coefficient calculation unit that calculates a coefficient obtained by dividing the sound volume by the volume of the received first voice as an initial setting value;
A coefficient storage unit that stores the coefficient calculated by the coefficient calculation unit;
The balance calculation unit calculates the volume balance by treating the volume obtained by multiplying the volume of the first sound received by the volume reception unit by the coefficient as the volume of the first sound in the mixed sound. The volume control system according to supplementary note 3 or 4, wherein the volume control system is provided.

(Appendix 6)
The volume control unit is
Including a target range storage unit that stores the target range including the reference balance but narrower than the reference range;
Any one of Supplementary notes 3 to 5, wherein the adjustment unit repeats volume adjustment of a sound produced by the sounding device until a sound balance within the target range is calculated by the balance calculation unit. The volume control system according to claim 1.

(Appendix 7)
The volume control unit is
A lower limit storage unit that stores a lower limit for the volume of the mixed voice measured by the voice measurement unit;
The adjusting unit prioritizes bringing the volume balance closer to the reference balance, and controls the volume of the sound produced by the sounding device so that the volume of the mixed sound measured by the sound measuring unit is equal to or higher than the lower limit. The volume control system according to any one of supplementary notes 3 to 6, wherein the volume control system is one that is adjusted.

(Appendix 8)
A sounding device that emits sound based on an audio signal at a volume adjusted by an instruction via a communication medium;
A voice observation unit for observing a first voice emitted by the sound generator;
An observation device having an audio transmission unit that transmits a first audio obtained by observation of the audio observation unit via a communication medium; and
A sound measuring unit that measures mixed sound in which the first sound emitted by the sounding device and the second sound from a source other than the sounding device are mixed;
An audio receiver for receiving the first audio transmitted from the audio transmitter;
By instructing the sounding device based on the first sound received by the sound receiving unit and the mixed sound measured by the sound measuring unit via a communication medium, the volume of the sound emitted by the sounding device is determined. A volume control unit that adjusts the volume balance between the first sound and the second sound in the mixed sound after the instruction so as to approach a predetermined reference balance;
A pronunciation system characterized by comprising

DESCRIPTION OF SYMBOLS 1 Sound generation system 1A, 200 Observation apparatus 1A_1 Sound observation part 1A_2,220 Voice transmission part 1B Control apparatus 1B_1 Sound measurement part 1B_2,120 Sound reception part 1B_3 Volume control part 2 Sound generation apparatus 10 TV system 20 Television 100 Remote control 101,201 Control IC
DESCRIPTION OF SYMBOLS 102 Memory 103 Operation button 104,202 Microphone 105,203 A / D conversion circuit 106,204 Wireless communication apparatus 107 Infrared communication apparatus 110 Remote control side sound measurement part 120 Audio | voice receiving part 130 Volume adjustment part 131 Operation volume adjustment part 132 Balance calculation part 133 Storage Unit 134 Range Determination Unit 135 Coefficient Determination Unit 136 Lower Limit Determination Unit 137 Automatic Volume Control Unit 210 TV Side Sound Measurement Unit

Claims (5)

A sound observing unit for observing a first sound emitted by a sounding device that emits sound based on a sound signal at a volume adjusted by an instruction via a communication medium;
An observation device having an audio transmission unit that transmits a first audio obtained by observation of the audio observation unit via a communication medium; and
A sound measuring unit that measures mixed sound in which the first sound emitted by the sounding device and the second sound from a source other than the sounding device are mixed;
An audio receiver for receiving the first audio transmitted from the audio transmitter;
By instructing the sounding device based on the first sound received by the sound receiving unit and the mixed sound measured by the sound measuring unit via a communication medium, the volume of the sound emitted by the sounding device is determined. A volume control unit that adjusts the volume balance between the first sound and the second sound in the mixed sound after the instruction so as to approach a predetermined reference balance;
A volume control system characterized by comprising: The volume control unit is
A balance calculating unit that calculates the volume balance in the mixed sound based on the first sound received by the sound receiving unit and the mixed sound measured by the sound measuring unit;
For the volume balance, a reference range storage unit that stores a reference range including the reference balance;
An adjustment unit that adjusts the volume of the sound generated by the sound generation device so that the volume balance in the mixed sound approaches the reference balance;
The volume adjustment according to claim 1, further comprising: an adjustment start unit that causes the adjustment unit to start adjusting the volume when the volume balance calculated by the balance calculation unit is out of the reference range. system. The volume control unit is
In response to an operation for instructing the initial setting from the user, the sound measurement unit measures the mixed sound at the time of the operation, and the volume receiving unit receives the first sound at the time of the operation, and the measured mixed sound A coefficient calculation unit that calculates a coefficient obtained by dividing the sound volume by the volume of the received first voice as an initial setting value;
A coefficient storage unit that stores the coefficient calculated by the coefficient calculation unit;
The balance calculation unit calculates the volume balance by treating the volume obtained by multiplying the volume of the first sound received by the volume reception unit by the coefficient as the volume of the first sound in the mixed sound. The volume control system according to claim 2, wherein the volume control system is provided. The volume control unit is
Including a target range storage unit that stores the target range including the reference balance but narrower than the reference range;
4. The volume according to claim 2, wherein the adjustment unit repeats volume adjustment of a sound produced by the sounding device until a sound balance within the target range is calculated by the balance calculation unit. Adjustment system. A sounding device that emits sound based on an audio signal at a volume adjusted by an instruction via a communication medium;
A voice observation unit for observing a first voice emitted by the sound generator;
An observation device having an audio transmission unit that transmits a first audio obtained by observation of the audio observation unit via a communication medium; and
A sound measuring unit that measures mixed sound in which the first sound emitted by the sounding device and the second sound from a source other than the sounding device are mixed;
An audio receiver for receiving the first audio transmitted from the audio transmitter;
By instructing the sounding device based on the first sound received by the sound receiving unit and the mixed sound measured by the sound measuring unit via a communication medium, the volume of the sound emitted by the sounding device is determined. A volume control unit that adjusts the volume balance between the first sound and the second sound in the mixed sound after the instruction so as to approach a predetermined reference balance;
A pronunciation system characterized by comprising

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