JP2006109106A - Multi-microphone apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multi-microphone apparatus with which a response to eliminate an external noise is performed even when the external noise is generated in its outdoor use, etc. and with which a wide range of directivity is taken when there is no external noise. <P>SOLUTION: The multi-microphone apparatus 1 has a nondirectional microphone 10, a single directivity microphone 20, a sound collection microphone C which collects noise to be a standard to control on/off of the nondirectional microphone, amplification means 35, 36 of both microphones, a synthetic means 38 for synthesizing voice signals amplified by the amplification means, a support member 2 which supports both microphones 10, 20 at an interval with a prescribed angle, a switching means 37 for performing on/off of the nondirectional microphone and a control means B1 for generating a control signal to perform on/off control of the switching means when the noise collected from the sound collection microphone exceeds a preset threshold. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a multi-microphone device having both unidirectional and omnidirectional characteristics, which is used for an announcer, a caster and the like of a television station.

  Various conventional microphones for pin microphones have been proposed, such as ultra-small and high-performance microphones (see Non-Patent Document 1, for example). In this microphone, a diaphragm, a spacer, and a back plate are arranged facing each other in the direction along the cylinder axis in that order, and a front chamber is arranged facing the diaphragm. The insulator is disposed so as to face the back plate to constitute the acoustic transducer unit. A net is placed at one end of the cylindrical case, and the acoustic exchanger is placed vertically, preventing deterioration of sound quality and minimizing adverse effects of foreign matter such as external sweat on the diaphragm. It is possible to achieve high sensitivity and low noise.

  As another example of the small microphone, there is a configuration shown in FIG. 6 (see, for example, Patent Document 1). FIG. 6 is a schematic diagram schematically showing a configuration of a conventional microphone device. The microphone device 50 is a first microphone 51 that is a bidirectional microphone and a second microphone that is an omnidirectional microphone that is disposed close to the microphone 51 (for example, a gap between the two is less than 1 centimeter). A microphone 52, a phase shifter 53 provided to the second microphone 52 via an amplifier, a subsequent stage of the phase shifter 53, and a correlation signal extraction circuit 54 connected from the first microphone 51 via the amplifier. is there.

  The phase shifter 53 shown here is a phase shift unit that shifts the phase of the output signal of the second microphone 52 obtained through the amplifier and makes the two output signals S1 and S2 in a specific angle range in phase or in phase. It is a functioning circuit. Here, since the first microphone 51 is a bidirectional microphone and the second microphone 52 is an omnidirectional microphone, the phase shifter 53 causes the phase of the output signal from the second microphone 52 to be 90 degrees or −90 degrees. Is shifting.

  Further, the correlation signal extraction circuit 54 determines a specific correlation coefficient between the output signal S2 of the second microphone 52 phase-shifted by the phase shifter 53 and the output signal S1 of the first microphone 51 obtained through the amplifier. Is a circuit that functions as a correlation signal extraction unit that extracts a portion having a sine wave and outputs it as a component of a sound wave from a range (specific angle range) of 180 degrees on the front side of the microphone 51 that is a bidirectional microphone.

  Note that the phase shifter 53 and the correlation signal extraction circuit 54 are configured so that the phase difference between the output signals relating to the sound waves incident on the first and second microphones 51 and 52 from a specific angle range and other angle ranges (the specific angle range). The component of the sound wave from the specific angle range is extracted from the output signal of both microphones 51 and 52 based on the difference from the phase difference of the output signal regarding the sound wave incident on both microphones 51 and 52 from the different angle range). Functions as an extraction means.

  Therefore, the phase shifter 53 shifts the phase of the output signal from the second microphone 52 so that the two output signals in a specific angle range are in phase or opposite phase, and the correlation signal extraction circuit 54 A portion having a specific correlation coefficient is extracted from the output signal S2 phase-shifted by the above and the output signal S1 of the first microphone 51, and set as a sound wave component from the specific angle range. Thereby, the microphone device 50 is a sound wave collected by both the microphones 51 and 52, and only the component of the sound wave incident from a specific narrow angle range (here, a range of 180 degrees on the front side of the first microphone 51). It can be accurately extracted.

In addition, a sound case generator that can perform low-frequency sensitivity correction in short-range sounds using two omnidirectional microphones has been proposed (see, for example, Patent Document 2). This sound case synthesis device forms a pressure gradient microphone from two omnidirectional microphones, which are pressure microphones, by sound field processing, and converts a signal from the omnidirectional microphone from a directional signal including a proximity sound. The proximity sound is extracted by subtraction. Therefore, according to this sound case generator, the low-frequency sensitivity in the short-range sound is corrected, and the near-field sound is further subtracted by actively using the extracted close-in sound to touch the microphone built-in device. Noise and wind noise can also be reduced.
http: www. sanken-mic. com / japanes / ja_index. html JP 2004-72630 A (paragraph numbers 0050 to 0053, FIGS. 1 to 5) JP 2002-218583 (paragraph numbers 0010 to 0074, FIGS. 1 to 14)

  However, the conventional microphone has the following problems. In other words, if the place where the announcer used in a TV station, etc., or a pin microphone that is a caster microphone is used, is not a studio installed in a building but outdoors, even a sound that you do not want to collect with a microphone. There were many cases where sound was collected, and improvement was desired.

  In addition, when using a microphone outdoors, when there is no noise, even if an announcer is operated, the sound is collected in a wide range as much as possible in order to stabilize the sound collection state, and external noise is In the case of occurrence, it is desired to be able to collect sound in a narrow range so as to eliminate the noise, but as in the configuration described in Patent Document 1, it is simply collected in a narrow directivity range. The sound alone could not be handled.

  Furthermore, the apparatus shown in Patent Document 2 is for the purpose of disturbing the uniform frequency-sensitivity characteristics of the microphone due to the so-called proximity effect and forcing noise generated in the vicinity of the microphone such as wind noise. When the external noise occurs irregularly, the external noise is excluded as much as possible, and the microphone is not configured to collect only the user's voice.

  Therefore, even when external noise is generated when using the microphone, the external noise is eliminated, and only the announcer's voice can be collected as much as possible. If there is no external noise, the microphone directivity is not affected. In addition, there has been a demand for a microphone capable of smoothly collecting a live broadcast program or program recording work so that sound can be collected with good sound quality and sound volume.

  The present invention was devised in view of the above problems, and can be used not to collect external noise even when external noise occurs, such as when used outdoors, and when there is no external noise. It is an object of the present invention to provide a multi-microphone device with a wide directivity range.

    In order to solve the above-described problems, a multi-microphone according to the present invention includes a unidirectional microphone having directivity in one direction, an omnidirectional microphone having no directivity in a specific direction, and the omnidirectional microphone. A sound collecting microphone that collects noise as a reference for turning on / off the input, an amplifying means for amplifying the sound signals of the unidirectional microphone and the omnidirectional microphone, and a sound signal amplified by the amplifying means Combining means, supporting means for supporting the unidirectional microphone and the omnidirectional microphone with a predetermined angle interval, and for turning on and off the omnidirectional microphone supported by the supporting means. A switching means and a control signal for performing on / off control of the switching means are used as a signal level of noise collected from the sound collecting microphone. There are those comprising a control means for generating if it exceeds a preset threshold value, a.

  With this configuration, when the signal level of the noise collected from the sound collecting microphone exceeds a preset threshold value, the multi-microphone device generates a control signal and activates the switching means. The omnidirectional microphone is turned off. In addition, the multi-microphone device uses the amplification means to amplify the sound collected from the omnidirectional microphone and the unidirectional microphone if the signal level of the noise collected from the sound collecting microphone does not exceed a preset threshold value. Amplified, synthesized by the synthesis means, and output.

  Furthermore, the multi-microphone device according to the present invention is the multi-microphone device according to claim 1, wherein the control means generates the unidirectional directional microphone when generating a control signal for turning off the omnidirectional microphone. An amplification control signal for amplifying the signal level by a preset value is generated.

  With this configuration, the multi-microphone device allows the sound signal collected from the omnidirectional microphone and the unidirectional microphone to exceed the threshold value, so that the control signal generated from the control means can pass through the switching means. When switching to a unidirectional microphone, the amplification means generates an amplification control signal so that the signal level of the sound of the unidirectional microphone is amplified from the control means, and the volume when the omnidirectional microphone is turned off is adjusted. To do.

  The multi-microphone device according to the present invention is the multi-microphone device according to claim 1 or 2, wherein the threshold is a first threshold set in advance and a predetermined value is separated from the first threshold. A second threshold value to be set, and the control means generates a control signal for turning on and off the omnidirectional microphone based on the first threshold value and the second threshold value.

  With this configuration, the multi-microphone device has a certain level of width as the first and second thresholds for switching between the unidirectional microphone and the omnidirectional microphone. The frequency of the switching operation is suppressed.

  Furthermore, the multi-microphone device according to the present invention is the multi-microphone device according to claim 1, wherein the predetermined angle at the support means for supporting the omnidirectional microphone and the unidirectional microphone is the unidirectionality. When the microphone is supported in the vertical direction by the support means, the omnidirectional microphone is set in the range of 10 degrees to 90 degrees with respect to the unidirectional microphone.

  With this configuration, the multi-microphone device is in a state in which no omnidirectional microphone and unidirectional microphone do not occur, and at most 90 degrees with respect to the vertical unidirectional microphone. Minimize unnecessary omnidirectional microphones collecting unwanted noise.

The multi-microphone device according to the present invention has the following excellent effects.
The multi-microphone device is omnidirectional that can easily collect external sound by collecting the noise that becomes external noise with a sound collecting microphone when used in a place where unexpected external noise may occur, such as outdoors. Sound is switched from a directional microphone to a unidirectional microphone. Therefore, the multi-microphone device can output only the sound from the unidirectional microphone while minimizing the influence of the sound from the external noise. Therefore, the multi-microphone device according to the present invention makes it possible to smoothly carry out a live broadcast program or program recording work, particularly outdoors, while minimizing the influence of external noise.

  The multi-microphone device amplifies the sound collected from the unidirectional microphone when the omnidirectional microphone is turned off from the sound level collected from both the unidirectional microphone and the omnidirectional microphone. Therefore, it is possible to output at a voice level without a sense of incongruity due to switching, and to remove external noise. It should be noted that the switching operation by the switching means can be faded out, so that the switching operation can be performed without any further discomfort.

  Since the multi-microphone device switches between the unidirectional microphone and the omnidirectional microphone according to the first threshold value and the second threshold value, the threshold value has a certain level width, and the switching operation does not occur unnecessarily continuously. . Therefore, the multi-microphone device can perform output from the unidirectional microphone in a state where the external noise is surely removed by stable operation, and when the cause of the external noise disappears, It is possible to switch to both microphone and omnidirectional microphone.

  In the multi-microphone device, the unidirectional microphone and the omnidirectional microphone that are supported by the supporting means are set in the range of 10 degrees to 90 degrees, so that howling does not occur and unnecessary noise is generated. Minimize sound collection.

Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing each configuration of the multi-microphone device, FIG. 2 is a perspective view showing the unidirectional microphone and the omnidirectional microphone of the multi-microphone device in a partially cut state, and FIG. It is a graph which shows the example of 1 threshold value and 2nd threshold value.

  As shown in FIG. 1 and FIG. 2, the multi-microphone device 1 includes a microphone sound collection unit A that collects sound, a sound processing unit B that processes sound collected by the microphone sound collection unit A, and a microphone collection unit. In order to control the sound part A, a sound collecting microphone C that collects external noise is provided. Note that the sound collected by the microphone sound collecting unit A is output from the speaker 45 via the sound processing unit B or the like.

  The microphone sound collecting unit A includes a non-directional microphone 10 having no directivity in a specific direction and a unidirectional microphone 20 having directivity in one direction via a microphone support cylinder 2 as a support means. It is supported at a predetermined angle. The voice processing unit B includes a control unit B1 and a processing unit B2. The sound collecting microphone C is disposed away from the microphone sound collecting portion A, and an omnidirectional microphone having no directivity in a specific direction is used here.

  Note that the multi-microphone device 1 is provided with a control unit B1 and a processing unit B2 that are distributed to either or each of the receiver main body 30 and the mixer unit 40 as the audio processing unit B. 30 is provided with a control unit B1 and a processing unit B2.

  The microphone support cylinder 2 of the multi-microphone device 1 is formed in a Y shape, and is separated from the vertical cylinder 2a formed in the vertical direction (vertical direction) by a predetermined angle α with respect to the vertical cylinder 2a. And an inclined cylinder portion 2b formed in the above manner. The microphone support cylinder 2 supports the unidirectional microphone 20 on the vertical cylinder portion 2a, and supports the omnidirectional microphone 10 on the inclined cylinder portion 2b.

  Further, here, the microphone support cylinder 2 is formed with a vertical cylinder portion 2a and an inclined cylinder portion 2b so as to support both microphones 10 and 20 with a predetermined angle α being separated by 30 degrees. The predetermined angle α supporting both the microphones 10 and 20 is set in a range of 10 degrees to 90 degrees. When the predetermined angle α in the microphone support cylinder 2 is arranged in a state smaller than 10 degrees, both the microphones 10 and 20 are too close to each other to cause howling. In addition, when the angle exceeds 90 degrees, there is a high possibility that the omnidirectional microphone 10 collects unnecessary sounds such as a user's rubbing.

The predetermined angle α for supporting both microphones 10 and 20 is set in the range of 10 degrees to 90 degrees, preferably in the range of 15 degrees to 60 degrees, and more preferably in the range of 20 degrees to 45 degrees. .
The microphone sound collection unit A of the multi-microphone device 1 is shown here as having a wireless structure, and includes signal transmission means (not shown).

  As shown in FIG. 2, the omnidirectional microphone 10 is located at the opening end of the position that becomes the end of the inclined cylindrical portion 2 b at a position that is a predetermined angle α from the unidirectional microphone 20 that is arranged in the vertical direction. While mainly supporting the windproof cover 15, a conversion unit 10 </ b> A that mainly converts sound transmitted as vibration through the windproof cover 15 into an electrical signal is provided. And the conversion part 10A is provided with the diaphragm (vibration membrane) 11, the spacer 12, the back plate 13, the insulator 14, and the wind-proof cover 15 as an example.

  The unidirectional microphone 20 supports the windproof cover 26 at the opening end at the position that becomes the end of the vertical cylindrical portion 2a, and the conversion unit 20A is installed in the vertical cylindrical portion 2a. The conversion unit 20A includes a vibration plate (vibration membrane) 21, a spacer that vibrates the vibration plate 21 or an insulator 22 that supports the vibration plate in a freely oscillating manner, a back electrode 23 that is disposed to face the vibration plate, A directivity imparting plate 25 having a directivity hole and an acoustic resistance material, which is disposed so as to form a back air chamber 24 with respect to the back electrode 23, is mainly provided. Note that the configuration of the conversion unit 20A is not limited as long as it can have a single directivity set in advance.

  Here, the sound collecting microphone C is used by being disposed at a location separated from both the microphones 10 and 20, for example, used inside the both microphones 10 and 20 partitioned by a partition plate or the like outside. Sometimes, it is used by being arranged at a position where it can collect noise that is external noise from outside the section. The sound collecting microphone C is a wireless structure here, and the signal level of the collected noise is transmitted to the sound processing unit B and used to control the omnidirectional microphone 10.

  Next, the configuration of the audio processing unit B of the multi-microphone device 1 will be described with reference to FIG. As shown in FIG. 1, the audio processing unit B includes a control unit B1 that performs control for switching the omnidirectional microphone 10 on and off, and the omnidirectional microphone 10 is turned on and off by a control signal from the control unit B1. A processing unit B2 that synthesizes the sound of both microphones 10 and 20 by adjusting the value amplified by the unidirectional microphone 20 is provided. In addition, the sound from both microphones 10 and 20 is configured to be output through a speaker 45 from a mixer unit 40 including a sound signal reproducing means 41 for reproducing.

  The control unit B1 includes an AD converter 31 that AD converts the audio signal from the sound collection microphone C, and a signal level detector (signal level detection means) that detects the signal level of the digital signal AD-converted by the AD converter 31. ) 32, and a signal level comparator (signal level comparing means) 33 that compares the signal level detected by the signal level detector 32 with a preset threshold value, and a result of comparison by the signal level comparator 33. A microphone switching controller 34 (switching output means) that outputs a control signal for turning on and off the omnidirectional microphone 10 and outputs an amplification control signal to the amplifier 35 of the unidirectional microphone 20 described later. It is equipped with.

The AD converter 31 converts the analog audio signal sent from the sound collecting microphone C into a digital audio signal. The AD converter 31 is configured corresponding to the type of microphone used as the sound collecting microphone C here.
The signal level detector 32 detects the power of the digital audio signal sent from the AD converter 31 as an audio level.

  The signal level comparator 33 receives the audio level value of the digital audio signal sent from the signal level detector 32 and preset first and second threshold values stored in a memory (not shown) or the like (FIG. 3). Reference) and the compared value is in area 1 exceeding the first threshold, or in area 2 between the first and second thresholds, or the second threshold is A signal corresponding to whether it is in the lower area 3 is output to the microphone switching controller 34. When setting the threshold values (first threshold value, second threshold value), the threshold values can be set from a switch such as a dip switch (DIPswitch), which is a threshold setting unit (not shown). This threshold setting means (not shown) is provided in the receiver main body 30 including the control unit B1 (or the mixer unit 40 if the control unit B1 is the mixer unit 40).

  As shown in FIG. 3, the first threshold value and the second threshold value set and used by the signal level comparator 33 are set to have a predetermined width as different values. In FIG. 3, the vertical axis represents signal level (dB), and the horizontal axis represents time (seconds) (t). Here, as an example, the interval between the first threshold value and the second threshold value is set to 5 dB. The first threshold is a threshold for turning off the omnidirectional microphone 10 and switching to the unidirectional microphone 20 when unexpected external noise occurs. The second threshold is a threshold for turning on the omnidirectional microphone 10 and switching to a state where sound can be collected from both the unidirectional microphone 20 and the omnidirectional microphone 10 when there is no unexpected external noise. is there. These two threshold values can prevent a switching operation from being performed by providing a predetermined width.

  As shown in FIG. 3, the microphone switching controller 34 is an area in which the signal sent from the signal level comparator 33 exceeds the area 2 and the first threshold from the state of the signal corresponding to the area 3 below the second threshold. Control signal and amplification control when the signal corresponds to 1 or when the signal corresponds to area 2 and area 3 below the second threshold from the state of the signal corresponding to area 1 exceeding the first threshold A signal is generated.

  This microphone switching controller 34, when the signal sent from the signal corresponding to the area 3 becomes the signal corresponding to the area 1 beyond the area 2, the generated omnidirectional signal as the control signal and the amplification control signal. A control signal for turning off the microphone 10 is generated, and an amplification control signal for raising the amplification width of the unidirectional microphone 20 to a preset value is output.

  Further, the microphone switching controller 34 is omnidirectional as a control signal and an amplification control signal that are generated when the signal sent from the signal corresponding to the area 1 becomes the signal corresponding to the area 3 beyond the area 2. A control signal for turning on the directional microphone 10 is generated, and an amplification control signal for reducing the amplifying width of the unidirectional microphone 20 to a preset value is output. Here, 3 dB is set as a preset value by an amplification control signal for increasing or decreasing the unidirectional microphone 20.

  As shown in FIG. 1, the processing unit B2 includes amplifiers 35 and 36 as amplification means for amplifying the sound signals collected and converted by the microphones 10 and 20, and the sound signals amplified by the amplifiers 35 and 36. And a switching means 37 that is disposed between the amplifier 36 and the combining means 38 and switches the omnidirectional microphone 10 on and off. Here, the amplifiers 35 and 36 are configured to be installed corresponding to both the microphones 10 and 20, respectively, but may be one.

The switching means 37 uses, for example, a slider that changes the value infinitely to infinity. When a control signal is received, the switching means 37 is preset from a predetermined value to infinity, or preset from infinity. The switching operation is performed after a predetermined time (several microseconds) has elapsed until the predetermined value is reached. The switching means 37 used here is not particularly limited as long as the omnidirectional microphone 10 can be turned on / off. However, the switching means 37 is fed out (fade in) with a predetermined time difference. Thus, it is more preferable if the omnidirectional microphone can be turned on and off.
The synthesizing unit 38 synthesizes audio signals from both microphones 10 and 20 and outputs them to the mixer unit 40.

  Since the receiver body 30 including the switching unit 31 is described as a wireless configuration, a wireless receiver such as an antenna (see FIG. 2), a battery (not shown), or an output unit (not shown) to the mixer unit 40 is used. As necessary.

  As shown in FIG. 1, the mixer unit 40 reproduces the audio signal sent from the receiver body 30 as audio, or the audio signal reproduction means 41 that reproduces the audio signal reproduced by the audio signal reproduction means 41 to the speaker. An output means (not shown) for outputting, an adjusting means (not shown) for adjusting the volume of sound, and the like are provided. Here, the mixer unit 40 is configured to receive and process an audio signal from the receiver body 30 wirelessly.

  Next, the operation state of the multi-microphone device 1 will be described with reference to FIGS. 4 and 5 (refer to FIGS. 1 to 3 as appropriate). 4A and 4B are schematic views schematically showing the operation state of the multi-microphone device according to the present invention, and FIG. 5 shows unidirectionality in a state where the microphone sound collecting unit of the multi-microphone device is mounted. It is a schematic diagram which shows typically a non-directional sound collection range.

  As shown in FIG. 4 (a), for example, when a stage is installed outdoors and a stage is installed, and when a public program is broadcast live or recorded on the stage in the enclosure, the multi-microphone device 1 is used as an announcer. Will be explained. At this time, it is assumed that there is a train track near the stage, and it is expected that the train will pass every certain time and generate noise. Note that the sound collecting microphone C is disposed at a position away from the microphone sound collecting portion A, in this case, above the partition that surrounds the stage.

  The announcer attaches the microphone sound collecting part A of the multi-microphone device 1 to a site where it is easy to collect his / her voice such as a tie. Then, the receiver main body 30 is put on standby on the stage while being mounted on a belt or the like. At this time, the mixer unit 40 (see FIG. 1) and the speaker 45 (see FIG. 1) are also installed at predetermined positions suitable for the audience, such as around the stage.

  Actually, when the program starts and the talk of the announcer is started, as shown in FIG. 1, in the multi-microphone device 1, the sound from the unidirectional microphone 20 and the omnidirectional microphone 10 is processed by the processing unit B1. Are sent from the output means (not shown) to the mixer section 40 through the synthesis means 38. The sound from the unidirectional microphone 20 or the unidirectional microphone 20 and the omnidirectional microphone 10 is reproduced via the audio signal reproducing means 41 of the mixer unit 40 and output from the speaker 45.

  Here, the first threshold value and the second threshold value are set so as to open a value of 5 dB as a threshold value when the omnidirectional microphone 10 is turned on / off. Therefore, as shown in FIG. 3, when the audio signal level exceeds a certain value, the omnidirectional microphone 10 is turned on / off.

  During the program, for example, as shown in FIG. 4B, when the train T gradually approaches the stage, the sound collecting microphone C collects a wide range of sounds, so the train T travels on the track. When the noise N is collected and exceeds the first threshold, a signal corresponding to the area 1 indicating the state exceeding the first threshold is output from the signal level comparator 33 to the microphone switching controller 34, A control signal and an amplification control signal are output from the control unit B1 to the processing unit B2.

  Then, the processing unit B2 that has received the control signal and the amplification control signal turns off the omnidirectional microphone 10 by setting the slider of the switching unit 37 to infinity so that the omnidirectional microphone 10 is faded out. At the same time, the processing unit B2 increases the value amplified by the amplifier 35 of the unidirectional microphone 20 by 3 dB from the preset value. Even when the amplifier 35 is amplified by 3 dB, the sense of discomfort of the audio to the viewer due to the switching is mitigated by operating the omnidirectional microphone 10 so as to fade in corresponding to the faded out state.

  When the omnidirectional microphone 10 is in an off state, the sound collection range TE that can be collected by the unidirectional microphone 20 from the sound collection range ME that can be collected by the omnidirectional microphone 10, as shown in FIG. The range is narrowed.

  Since the unidirectional microphone 20 is installed in the vertical direction, even if the announcer needs some action in the course of the program and the talk is made while moving the neck to the left or right, the sound can be sufficiently collected. It has become. When the signal corresponding to area 2 where the signal level is between the first threshold value and the second threshold value is output from the signal level detector 33 to the microphone switching controller 34, the control unit B1 outputs the signal to the processing unit B2. In contrast, the control signal and the amplification control signal are not output.

  As the train T gradually moves away from the stage, as shown in FIG. 4A, the noise N also gradually moves away, and again, the signal level of noise, which is external noise collected from the sound collecting microphone C, is When the signal of the first threshold area 1 falls below the second threshold value to become the signal of area 3, the control signal and the amplification control signal are output from the control unit B1 to the processing unit B2. That is, when the external noise is reduced, the multi-microphone device 1 is in a state of collecting sound by the omnidirectional microphone 10 and the unidirectional microphone 20.

  At this time, the processing unit B2 turns on the omnidirectional microphone 10 by setting the slider, which has been made infinite by operating the switching unit 37, to a position of a value preset by the control signal. At the same time, the processing unit B2 controls the amplifier 35 to amplify to a certain value preset by the amplification control signal from the state where the value to be amplified is increased by 3 dB. Therefore, the multi-microphone device 1 outputs the sound collected from the unidirectional microphone 20 and the omnidirectional microphone 10 from the speaker 45.

  As shown in FIGS. 4A and 4B, the noise N of the train T has been described as an example here, but the type of noise is not limited, and external noise is generated in an unexpected state. Even in such a case, similarly, the omnidirectional microphone 10 can be switched on and off, so that the program recording or the live broadcast program can be performed as an audio state with little trouble in program progression. The first threshold value and the second threshold value can be set to arbitrary values.

  As described above, the omnidirectional microphone 10 can be switched on and off according to the surrounding conditions of the microphone sound collecting unit A of the multi-microphone device 1, so that the sound volume and sound quality are best in various situations. Sound collection is possible. Further, compared to a conventional pin microphone (only omnidirectional or only unidirectional), it can be configured with an equivalent size.

Further, in the multi-microphone device 1 described with reference to FIGS. 1 and 5, the user who wears the microphone sound collecting unit A can switch the manual switch (not shown) as a switching unit without using the sound collecting microphone C. It doesn't matter. The timing for switching with the manual switch is when the user determines that external noise has occurred.
Note that the present invention is not limited to the description of the above-described embodiment, and various modifications that embody the technical idea of the present invention can be added.

It is a block diagram which shows each structure of the multimicrophone apparatus based on this invention. It is a perspective view in the state where a part was notched which shows the omnidirectional microphone and unidirectional microphone of the multi-microphone apparatus concerning the present invention. It is a graph which shows the example of the 1st threshold value and the 2nd threshold value in the multimicrophone apparatus concerning the present invention. (A), (b) is a schematic diagram which shows typically the operation state of the multimicrophone apparatus based on this invention. It is a schematic diagram which shows typically the unidirectional and non-directional sound collection range in the state which mounted | wore with the microphone sound collection part of the multimicrophone apparatus which concerns on this invention. It is a block diagram which shows the conventional microphone apparatus.

Explanation of symbols

A microphone sound collection unit B audio processing unit B1 control unit B2 processing unit 1 multi-microphone device 2 microphone support cylinder (support means)
DESCRIPTION OF SYMBOLS 10 Non-directional microphone 10A Conversion part 20 Unidirectional microphone 20A Conversion part 30 Receiver main body 31 AD converter 32 Signal level detector (signal level detection means)
33 Signal level comparator (signal level comparison means)
34 Microphone switching controller (switching output means)
35 Amplifier (amplification means)
36 Amplifier (amplification means)
37 switching means 38 synthesis means 40 mixer section 41 audio signal reproduction means 45 speaker

Claims (4)

  A unidirectional microphone that is directional in one direction, an omnidirectional microphone that is not directional in a specific direction, and a sound collecting microphone that collects noise that serves as a reference for turning on and off the input of the omnidirectional microphone; Amplifying means for amplifying audio signals of the unidirectional microphone and the omnidirectional microphone, a synthesizing means for synthesizing the audio signals amplified by the amplifying means, the unidirectional microphone and the omnidirectional Support means for supporting the microphone with a predetermined angle interval, switching means for turning on and off the omnidirectional microphone supported by the support means, and a control signal for performing on / off control of the switching means Control means for generating when the signal level of the noise collected from the sound collection microphone exceeds a preset threshold; Multi-microphone device provided.   The control means generates an amplification control signal for amplifying a signal level of the unidirectional directional microphone by a preset value when a control signal for turning off the omnidirectional microphone is generated. The multi-microphone device according to claim 1, wherein   The threshold value includes a first threshold value set in advance and a second threshold value set apart from the first threshold value by a predetermined value, and the control means is based on the first threshold value and the second threshold value. The multi-microphone device according to claim 1, wherein a control signal for turning on and off the omnidirectional microphone is generated. The predetermined angle at the supporting means for supporting the unidirectional microphone and the omnidirectional microphone is such that when the unidirectional microphone is supported by the supporting means in the vertical direction, the unidirectional microphone The multi-microphone device according to claim 1, wherein the omnidirectional microphone is set in a range of 10 degrees to 90 degrees.

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