JP2009021657A - Sound radiation and pickup device and sound radiation and pickup system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sound radiation and pickup device which can have microphone directivities and speaker directivities controlled although having a compact housing. <P>SOLUTION: A nondirectional microphone 13 and bidirectional microphones 12A and 12B are installed in the center of the housing, and speakers 11A to 11C are installed at the same distance from the center of the housing and at rotation of 120°. A plurality of sound pickup directivities are set peripherally around the housing by controlling amplification amounts and phases of audio signals picked up by the respective microphones. Further, two out of the speakers 11A to 11C are driven and amplification amounts and delay amounts of audio signals to be supplied to those speakers are set to set sound radiation directivities. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a sound emission and collection device that collects sound and emits sound, and a sound emission and collection system that connects the sound emission and collection device to a network.

Conventionally, an apparatus that uses three microphones and can perform a good intercom call in a noisy environment has been proposed (see, for example, Patent Document 1). An apparatus that detects the direction of a speaker with a microphone array and directs directivity toward the direction of the speaker with a speaker array has also been proposed (see, for example, Patent Document 2).
Japanese Patent Laid-Open No. 10-336306 JP 2006-270876 A

However, the device of Patent Document 1 cannot control microphone directivity and speaker directivity.
Further, the apparatus of Patent Document 2 has a problem in that the housing becomes large because a large number of microphones and speakers must be arranged at a certain interval.

  Accordingly, an object of the present invention is to provide a sound emitting and collecting apparatus and a sound emitting and collecting system that can control microphone directivity and speaker directivity while being a compact housing.

  A sound emission and collection device according to the present invention includes a sound collection unit composed of a unidirectional microphone or an omnidirectional microphone, one or more bidirectional microphones, and a sound emission unit formed by arranging a plurality of speakers in close proximity. And a sound collection directivity control unit that sets the sound collection directivity around the apparatus main body by controlling the level and phase of the sound signal collected by each microphone of the sound collection unit, and supplies it to a plurality of adjacent speakers And a sound emission directivity control unit that controls the sound emission directivity by controlling the level and delay amount of the sound signal to be transmitted.

In this configuration, the sound collection directivity is controlled by controlling the level and phase of audio signals collected by a plurality of microphones. For example, when the levels of the sound signals collected by the omnidirectional microphone and the bidirectional microphone are made the same, the sound collection level becomes the highest in the region having the same phase, and directivity is formed. Here, if the phase of the audio signal collected by the bidirectional microphone is inverted, directivity is formed in the opposite direction. Furthermore, directivity can be formed in a plurality of directions by providing a plurality of bidirectional microphones.
Further, the directivity of sound emission is controlled by a speaker installed in the vicinity. The sound emission directivity means that a high level of sound is emitted in a specific direction, and the concept of controlling the sound emission characteristics so as to focus the sound emission at a specific position around the device, It includes the concept of controlling the sound emission characteristics so that a sound source is virtually formed at a specific position.
Controls the level and phase using an omnidirectional microphone or a bi-directional microphone, and controls the level and delay using a close speaker, so the microphone and speaker directivity are controlled in a compact housing. be able to.

  Further, according to the present invention, the plurality of speakers of the sound emitting unit are arranged so as to rotate at an equal angle around the sound collecting unit around the sound collecting unit, and the sound emitting directivity control unit includes: It is characterized in that the level and delay amount of an audio signal supplied to two speakers installed in parallel in a direction orthogonal to the central axis of the range for controlling sound emission directivity are controlled.

  In this configuration, a plurality of speakers are installed at an equal angle around the sound collection unit. Two of these speakers are driven to control sound directivity. By selecting a speaker to be driven, sound emission directivity can be set in a plurality of directions around the apparatus.

  A sound emission and collection device according to the present invention includes a sound collection unit including an omnidirectional microphone provided at a center position of the upper surface of the housing, and two bidirectional microphones whose sound collection areas are orthogonal to each other; A sound emitting unit composed of a plurality of speakers arranged equidistant from the center position and close to each other, and a level of a sound signal collected by the omnidirectional microphone are set, and the two bidirectional microphones are set. The level of the audio signal picked up by either one or both is set to be the same as the level of the sound signal picked up by the omnidirectional microphone, and either one of the two bidirectional microphones, or Close to the sound collection directivity control unit that sets the sound collection directivity around the case by inverting the phase of the sound signal collected by both or by synthesizing both sound signals as they are Sound supplied to multiple speakers Characterized by comprising a sound emission directivity control unit for controlling the sound emission directivity by controlling the level and delay amount of the signal.

In this configuration, an omnidirectional microphone and two bidirectional microphones whose sound collection areas are orthogonal to each other are installed at the center of the casing. Here, by controlling the level and phase of the audio signal collected by each microphone, a plurality of sound collection directivities can be set in the entire circumferential direction of the housing. For example, if the levels of the audio signals collected by all the microphones are made the same, the sound collection level becomes the highest in the region where the phases of all the audio signals are the same, and in this direction (for example, the right side of the back of the housing) Form directivity. Here, when the phase of an audio signal picked up by one of the two bidirectional microphones is reversed, directivity is formed in a direction inclined by 90 degrees (for example, the left side of the housing). In addition, only the sound signal picked up by one of the bidirectional microphones is set to the same level as the sound signal picked up by the omnidirectional microphone, thereby forming directivity in the meantime (for example, in the rear direction of the housing). .
Further, the directivity of sound emission is controlled by a speaker installed in the vicinity.
Controls the level and phase using an omnidirectional microphone or a bi-directional microphone, and controls the level and delay using a close speaker, so the microphone and speaker directivity are controlled in a compact housing. be able to.

  Further, according to the present invention, the plurality of speakers are arranged so as to rotate at an equal angle around the center of the housing, and the sound emission directivity control unit is a central axis of a range for controlling the sound emission directivity The level and delay amount of the audio signal supplied to two speakers installed in parallel in a direction orthogonal to the direction are controlled.

  In this configuration, a plurality of speakers are installed at an equal angle around the center of the casing. Two of these speakers are driven to control sound directivity. By selecting a speaker to be driven, sound emission directivity can be set in a plurality of directions around the apparatus.

  A sound emission and collection system according to the present invention is a sound emission and collection system in which a plurality of sound emission and collection devices according to any one of claims 1 to 4 are connected via a network, and the sound emission and collection device Comprises a communication unit that transmits the audio signal synthesized by the sound collection directivity control unit to another device, receives the audio signal from the other device, and supplies the audio signal to the sound emission directivity control unit. To do.

  According to the present invention, while controlling the level and phase of an audio signal picked up by a plurality of microphones, and controlling the level and delay amount of an audio signal supplied to a nearby speaker, it is a compact housing. Microphone directivity and speaker directivity can be controlled.

  Hereinafter, a sound emission and collection system according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a sound emission and collection system. FIG. 2 is a diagram showing an appearance of a terminal used in the system, and FIG. 3 is a block diagram showing a configuration of the terminal. This sound emission and collection system is realized by a plurality of terminals connected via a PLC (Power Line Communications) network. Note that the network mode in the present invention is not limited to the PLC. In this embodiment, an A / D converter, a D / A converter, and the like are omitted, and unless otherwise specified, all audio signals transmitted through the apparatus are digital audio signals. In FIG. 2, the upper side of the paper is the back direction of the terminal, the lower side of the paper is the front direction of the terminal, the right side of the paper is the left surface direction of the terminal, and the left side of the paper is the right surface direction of the terminal.

  In FIG. 1, the sound emission and collection system includes a plurality of terminals 1A to 1D. Terminals 1A to 1D are installed in rooms A to D, respectively. Terminals 1A to 1D all have the same configuration and function, and FIG. 2 and FIG. 3 show the configuration of terminal 1A as a representative.

  The terminal 1A includes a speaker 11A, a speaker 11B, a speaker 11C, a microphone 12A, a microphone 12B, a microphone 13, a sound collection processing unit 3, an echo canceller 4, a control unit 5, a sound emission processing unit 7, an input / output interface (I / F). ) 9 and the operation unit 15.

  The terminal 1A is composed of a compact rectangular parallelepiped housing whose shape when viewed from the top is a square (or rectangle) having a side of about 15 cm, and the microphone 12A, the microphone 12B, and the microphone 13 are covered with a mesh steel plate. It is provided at the center position of the upper surface of the housing. The speaker 11A, the speaker 11B, and the speaker 11C are provided on the upper surface of the housing at an equal distance from the housing center by 120 degrees. Although not shown, the speaker 11A, the speaker 11B, and the speaker 11C are also covered with a mesh steel plate.

  The operation unit 15 is provided in the vicinity of the front end of the upper surface of the housing, and transmits an operation signal to the control unit 5 in accordance with an operation performed by the user. The controller 5 performs various operations according to the input operation signal. For example, when the user operates the operation unit 15 to change the volume setting, the control unit 5 sets the sound volume (amplification amount of the audio signal) of the sound emission processing unit 7 in accordance with the control signal.

  The input / output I / F 9 is provided on the front surface of the housing, and includes a power cable, an audio input terminal, and the like. Since this terminal is a terminal that performs network communication by PLC, a power cable connected to a household outlet becomes a network I / F. The terminal 1A inputs and outputs audio signals from these I / Fs. In FIG. 1, a terminal 1A transmits and receives an audio signal as audio information conforming to a predetermined protocol with other terminals in the network via an input / output I / F 9. The terminal 1A can input an audio signal (analog or digital audio signal) from the audio input terminal of the input / output I / F 9 and emit sound using the speakers 11A to 11C. It is not essential in the present invention. The arrangement of the operation unit 15 and the input / output I / F 9 is not limited to the example shown in FIG.

  The microphone 12A and the microphone 12B are bidirectional microphones. The microphone 13 is an omnidirectional microphone. The audio signal collected by these microphones is input to the sound collection processing unit 3. The sound collection processing unit 3 includes an amplifier 32A that amplifies the sound signal collected by the microphone 12A, an amplifier 32B that amplifies the sound signal collected by the microphone 12B, an amplifier 33 that amplifies the sound signal collected by the microphone 13; A post processor 35 is provided for adding the audio signals amplified by the amplifier and outputting them to the echo canceller 4 at the subsequent stage.

  The amplification amount of each amplifier and the addition mode of the post processor 35 are set by the control unit 5. When the control unit 5 performs these settings, sound collecting directivity in a plurality of directions can be provided around the casing of the terminal 1A. This directivity mode will be described with reference to FIG. FIG. 5 is a diagram showing the sound collection directivity of each microphone.

  First, the microphone 12A has a sound collection area 121A in the rear direction of the casing and a sound collection area 122A in the front direction of the casing. The phase of the sound signal collected in the sound collection area 121A and the sound signal collected in the sound collection area 122A are inverted. The microphone 12B has a sound collection region 121B in the left surface direction of the housing and a sound collection region 122B in the right surface direction of the housing. The phase of the sound signal collected in the sound collection area 121B and the sound signal collected in the sound collection area 122B are inverted. The microphone 13 has a uniform sound collection area 131 around the casing. The sound collection area 131 covers all of the sound collection area 121A, the sound collection area 122A, the sound collection area 121B, and the sound collection area 122B.

  The control unit 5 can control the directivity by controlling the amplification amount and phase of the audio signal collected from these sound collection areas. FIG. 6 is a diagram showing an example of the relationship between the amplification amount and phase and directivity. In the figure, a predetermined phase is indicated as “+”, and a phase inverted from the predetermined phase is indicated as “−”.

  First, FIG. 6A shows an example in which the sound signals collected in the sound collection area 121A, the sound collection area 121B, and the sound collection area 131 are all in the same phase “+”. The sound signals collected in the area where the sound collection area 121A and the sound collection area 131 overlap are emphasized when added because they have the same phase. Similarly, since the sound signals collected in the area where the sound collection area 121B and the sound collection area 131 overlap are in the same phase, they are emphasized when they are added. In addition, the sound signal collected in the area where the sound collection area 121A and the sound collection area 121B overlap is also emphasized. Therefore, the sound signal collected in the sound collection area 151 where all of these overlap is emphasized most. Therefore, if the amplification amounts of the amplifier 32A, the amplifier 32B, and the amplifier 33 are set to be the same, and the post-processor 35 is set to add all the audio signals in the same phase, the sound is directed toward the sound collection area 151 (the rear surface on the left side of the casing). Will be set.

  Here, when the post processor 35 is set to invert and add the sound signals collected by the microphones 12A and 12B, as shown in FIG. 5B, the sound collection regions 121A and 122A. , The phases in the sound collection area 121B and the sound collection area 122B are reversed with respect to FIG. Therefore, the sound signal collected in the sound collection region 152 where the sound collection region 122A, the sound collection region 122B, and the sound collection region 131 all overlap is most emphasized, and directivity is applied to the sound collection region 152 (the front right side of the housing). Will be set.

  Similarly, although not shown, when only the sound signal collected by the microphone 12A is inverted in phase with respect to FIG. 5A, the sound collection region 122A, the sound collection region 121B, and the sound collection region 131 all overlap. Directivity is set in the area (front side of the left side of the housing). Further, when the phase of only the sound signal collected by the microphone 12B is reversed with respect to FIG. 5A, the sound collecting area 121A, the sound collecting area 122B, and the sound collecting area 131 are all overlapped (the back on the right side of the housing). The directivity is set.

  Next, FIG. 6C shows that the amplification amount of the audio signal picked up by the microphone 12A and the sound signal picked up by the microphone 13 in FIG. An example of the case is shown. In the example of FIG. 5C, the sound signals collected in the area where the sound collection area 121A and the sound collection area 131 overlap (sound collection area 153) have the same phase, and therefore are emphasized when added. Therefore, when the amplification amounts of the amplifier 32A and the amplifier 33 are set to be the same, the amplification amount of the amplifier 32B is set to zero, and the post-processor 35 is set to add all audio signals in the same phase, the sound collection region 153 (housing) The directivity is set in the rear direction.

  FIG. 4D shows an example in which the phase of the audio signal collected by the microphone 12 </ b> A in FIG. As shown in FIG. 4D, the phases in the sound collection area 121A and the sound collection area 122A are inverted. Therefore, since the sound signals collected in the area where the sound collection area 122A and the sound collection area 131 overlap (sound collection area 154) have the same phase, they are emphasized when added. Therefore, if the amplification amounts of the amplifier 32A and the amplifier 33 are set to be the same, the amplification amount of the amplifier 32B is set to zero, and the audio signal collected by the microphone 12A is inverted by the post processor 35 and then added, the convergence is obtained. The directivity is set in the sound region 154 (the front direction of the housing).

  Similarly, although not shown, when the amplification amounts of the amplifier 32B and the amplifier 33 are set to be the same, the amplification amount of the amplifier 32A is set to zero, and the post processor 35 is set to add all audio signals in the same phase. The directivity is set in the direction of the left side of the casing. Further, when the amplification amounts of the amplifier 32B and the amplifier 33 are set to be the same, the amplification amount of the amplifier 32A is set to zero, and the sound signal collected by the microphone 12B is inverted by the post processor 35 and then added, The directivity is set in the right body direction.

  In the terminal 1A of the present embodiment, when the amplification amounts of the amplifier 32A and the amplifier 32B are set to zero, only the sound collected by the microphone 13 that is an omnidirectional microphone is output to the subsequent stage. Sound can also be picked up in the direction of the top surface.

  Here, the control unit 5 changes the amplification amount and phase of the audio signal collected by each microphone within a very short time, and collects the sound generated from the entire circumference direction (9 directions) of the housing. Then, the audio signal having the highest level is output to the echo canceller 4 as a subsequent stage as a sound collection signal.

  In FIG. 3, the echo canceller 4 inputs audio signals supplied from the sound emission processing unit 7 to the speakers 11A, 11B, and 11C. Each of these input signals is filtered and subtracted from the collected sound signal to remove the echo component. FIG. 4 shows the configuration of the echo canceller 4.

The echo canceller 4 includes an echo canceller 4A, 4B, 4C that inputs audio signals supplied to the speakers 11A, 11B, 11C, and an adder 43 that adds the signals output from the echo cancellers 4A, 4B, 4C, respectively. Yes. The echo cancellers 4A, 4B, and 4C all have the same configuration and function. Hereinafter, the configuration and function of the echo canceller 4A will be described as a representative. The echo canceller 4A includes an adaptive filter 41A and an adder 42A, and inputs an audio signal supplied from the sound emission processing unit 7 to the speaker 11A to the adaptive filter 41A. The adaptive filter 41A filters this audio signal, and generates a pseudo regression sound signal that simulates the regression audio signal that circulates from the speaker to the microphone. The adder 42A removes the echo component by subtracting the pseudo regression sound signal from the collected sound signal. The collected sound signal from which the echo component has been removed is input to the adder 43. Similarly, the echo components are removed from the collected sound signals in the echo cancellers 4B and 4C and input to the adder 43. The adder 43 adds these signals and transmits them to other terminals via the input / output I / F 9. The collected sound signal from which the echo component has been removed is input to the adaptive filter 41A and used to update the filter coefficient.
The echo canceller 4 is not an essential component in the present invention. However, since the echo canceller 4 removes echo components, the echo canceller 4 is suitable for a voice conference or the like using a plurality of terminals.

  Next, the sound emission processing unit 7 includes a delay 71A, a delay 71B, a delay 71C, an amplifier 72A, an amplifier 72B, and an amplifier 72C. The delay amount of each delay and the amplification amount of each amplifier are set by the control unit 5. By making these settings, the control unit 5 can provide sound emission directivity in a plurality of directions around the casing of the terminal 1A. In this embodiment, the sound emission directivity means that a high level sound is emitted in a specific direction, and the sound emission characteristics are controlled so that the sound emission is focused on a specific position around the device. And a concept of controlling sound emission characteristics so as to virtually form a sound source at a specific position.

  This sound emission directivity will be described with reference to FIG. FIG. 7 is a diagram showing the sound emission characteristics of the speaker. In the example of the figure, the speaker 11B and the speaker 11C are driven. That is, the amplification amount of the amplifier 72A is set to zero. Then, by controlling the delay amounts of the delay 71B and the delay 71C and the amplification amounts of the amplifier 72B and the amplifier 72C, the same is achieved at the position of the user 101 existing on the center line (in the front of the casing) of the two adjacent speakers. A plurality of virtual sound sources 51 to 54 as shown in the figure are formed. The virtual sound source shown in the figure is only an example. By controlling the amount of delay and the amount of amplification of the audio signal supplied to two adjacent speakers, and setting the time difference and volume difference of the sound reaching both ears, it is possible to set more virtual sound sources at the same time. The sound source can also be formed. Thereby, a stereophonic sound can be formed.

  The terminal 1A of the present embodiment can set the directivity as described above for users in different directions by changing the speaker to be driven. FIG. 8 is a diagram illustrating another example of the sound emission characteristics of the speaker. In the example of the figure, the speaker 11A and the speaker 11B are driven. That is, the amplification amount of the amplifier 72C is set to zero. Then, by controlling the delay amount of the delay 71A and the delay 71B and the amplification amount of the amplifier 72A and the amplifier 72B, at the position of the user 102 existing on the center line of the two adjacent speakers (in the left side of the housing), A plurality of virtual sound sources 61 to 64 as shown in FIG. Similarly, by driving the speaker 11A and the speaker 11C, a virtual sound source can be formed for a user who exists in the right side direction of the back of the housing.

  Further, according to the terminal 1A of the present embodiment, a virtual sound source can be formed even for a user who exists in a region far from the center line of the speaker to some extent by controlling the delay amount and the volume.

  The number of speakers and the manner of arrangement are not limited to this example. For example, only the speaker 11B and the speaker 11C may be installed, and the virtual sound source may not be formed on the right side of the back of the housing and the left side of the back of the housing. It is also possible to omit the speaker 11A and reduce the cost.

  Also, the number of speakers can be increased to four or more. By providing four speakers, a virtual sound source can be formed in eight directions around the apparatus, as with the sound collection directivity of the microphone. FIG. 9 is a diagram illustrating sound emission characteristics of a speaker of a terminal according to an application example. FIG. 10 is a block diagram illustrating a configuration of a terminal according to the application example. In addition, about the structure and function which are common in terminal 1A, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  This terminal 2A includes four speakers 91A to 91D. Since the terminal 2A includes four speakers, an audio signal supplied to each speaker is input to the echo canceller 4. The speakers 91 </ b> A to 91 </ b> D are provided by being rotated 90 degrees at equal distances from the center of the casing on the upper surface of the casing. Although not shown in this application example, the speakers 91A to 91D are also covered with a mesh steel plate.

  The sound emission processing unit 7 includes delays 71A to 71D and amplifiers 72A to 72D. The delay amount of each delay and the amplification amount of each amplifier are set by the control unit 5 similarly to the terminal 1A.

  In the terminal 2A according to the application example, a virtual sound source can be formed in eight directions by driving any two speakers. For example, the example of FIG. 9 shows an example in which the speaker 91A and the speaker 91C are driven, and an example in which the speaker 91C and the speaker 91D are driven.

  When the speakers 91A and 91C are driven, a virtual sound source can be formed for a user who is present on the right side of the front of the apparatus on the center line of these speakers. Similarly, when the speaker 91C and the speaker 91D are driven, a virtual sound source can be formed for a user existing in the front direction of the apparatus on the center line of these speakers. Thus, the virtual sound source can be formed in eight directions by the driving mode of the speaker.

  As described above, according to the terminal of the present embodiment, the microphone directivity and speaker directivity can be controlled while being a compact housing. That is, by driving two loudspeakers installed in close proximity to form a virtual sound source, and setting the sound collection directivity in the circumferential direction of the terminal using an omnidirectional microphone and two bidirectional microphones, Compared to the case where directivity is controlled by a speaker array, the housing can be made very compact.

  In the present embodiment, the example in which the sound collection directivity is controlled in nine directions by the omnidirectional microphone and the two bidirectional microphones has been described. The sound collection directivity may be controlled by a directional microphone and a bidirectional microphone.

It is a block diagram which shows the structure of a sound emission and collection system. It is a figure which shows the external appearance of a terminal. It is a block diagram which shows the structure of a terminal. 2 is a block diagram showing a configuration of an echo canceller 4. FIG. It is the figure which showed the sound collection directivity of each microphone. It is the figure which showed the example of a relationship between amplification amount and phase, and directivity. It is the figure which showed the sound emission characteristic of the speaker. It is the figure which showed another example of the sound emission characteristic of a speaker. It is the figure which showed the sound emission characteristic of the speaker of the terminal which concerns on an application example. It is a block diagram which shows the structure of the terminal which concerns on an application example.

Explanation of symbols

1-terminal 9-input / output I / F
12A, 12B, 13-Microphones 11A, 11B, 11C-Speaker 15-Operation part

Claims (5)

A sound collection unit including a unidirectional microphone or an omnidirectional microphone, and one or more bidirectional microphones;
A sound emitting part in which a plurality of speakers are arranged close to each other;
A sound collection directivity control unit that sets the sound collection directivity around the apparatus main body by controlling the level and phase of the sound signal collected by each microphone of the sound collection unit,
A sound output directivity control unit that controls the sound output directivity by controlling the level and delay amount of an audio signal supplied to a plurality of adjacent speakers;
A sound emission and collection device. The plurality of speakers of the sound emitting unit are arranged to rotate at an equal angle around the sound collecting unit with the sound collecting unit as a center,
The sound emission directivity control unit controls a level and a delay amount of an audio signal supplied to two speakers installed in parallel in a direction orthogonal to a central axis of a range in which the sound emission directivity is controlled. The sound emission and collection device according to 1. A sound collection unit comprising a non-directional microphone provided at the center position of the upper surface of the housing and two bidirectional microphones whose sound collection areas are orthogonal to each other;
A sound emitting unit that is arranged at an equal distance from the center position of the housing and includes a plurality of speakers that are close to each other;
The level of the voice signal picked up by the omnidirectional microphone is set, and the level of the voice signal picked up by one or both of the two bidirectional microphones is picked up by the omnidirectional microphone. Set to the same level as the audio signal,
In addition, after reversing the phase of the sound signal picked up by one or both of the two bidirectional microphones, or by synthesizing both sound signals as they are, they are collected around the casing. A sound collection directivity control unit for setting sound directivity;
A sound output directivity control unit that controls the sound output directivity by controlling the level and delay amount of an audio signal supplied to a plurality of adjacent speakers;
A sound emission and collection device. The plurality of speakers are arranged to rotate at an equal angle around the center of the housing,
The sound emission directivity control unit controls a level and a delay amount of an audio signal supplied to two speakers installed in a direction orthogonal to a central axis of a range in which the sound emission directivity is controlled. Sound emitting and collecting device. A sound emission and collection system in which a plurality of sound emission and collection devices according to any one of claims 1 to 4 are connected via a network,
The sound emission and collection device includes a communication unit that transmits an audio signal synthesized by the sound collection directivity control unit to another device, receives the audio signal from the other device, and supplies the audio signal to the sound emission directivity control unit. A sound collection system.

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