Detection device, mute device for wind instrument and calculation method for radiated sound wave

Abstract

To provide a detection device for more accurately detecting the playing state of a wind instrument.SOLUTION: A detection device 20 has a first actuator 21 that generates sound waves transmitted into a tube 3 of clarinet 1, a first sensor section 31 having a plurality of sensors 31a-31h that detect sound waves, and a first mounting section 41 that positions the first actuator 21 and the first sensor section 31 inside the tube 3. Respective sensors 31-31h of a plurality of sensors 31 are spaced apart from each other in the longitudinal direction of the tube 3.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a detection device, a mute device for a wind instrument, and a method for calculating a radiated sound waveform. [Background technology]

[0002] The system for representing the sound of a reed instrument described in the patent application WO 2005 / 023334 comprises a speaker arranged to deliver sound to an air chamber of the reed instrument, a microphone for receiving the sound of the air chamber, and a processing unit for receiving a measurement signal from the microphone. The processing unit generates an output signal from the measurement signal indicative of which musical note is being played by the reed instrument. The system further comprises a pressure sensor for sending a signal to the processing unit indicative of the user of the reed instrument blowing into it. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2018-521367 Summary of the Invention [Problem to be solved by the invention]

[0004] The system described in Patent Document 1 can identify the pitch by detecting the resonant frequency in the tube of a reed instrument, but cannot detect the open / closed state of each of the multiple sound holes in the reed instrument, and therefore cannot obtain sufficient parameters used to calculate the radiated sound waveform. Therefore, it is difficult for the conventional system to accurately grasp the playing state of a reed instrument. In consideration of the above circumstances, one aspect of the present disclosure aims to more accurately detect the playing state of a wind instrument. [Means for solving the problem]

[0005] In order to solve the above problems, a detection device according to one embodiment of the present disclosure comprises a generating unit that generates waves that propagate within a tube of a wind instrument, and a first sensor unit having a plurality of sensors that detect the waves, wherein the generating unit and the first sensor unit are disposed within the tube, and each of the plurality of sensors is disposed at intervals from one another in the longitudinal direction of the tube.

[0006] A detection device according to one aspect of the present disclosure includes a first actuator that generates sound waves by vibrating the air inside a tube of a wind instrument, a first sensor unit having a plurality of sensors that detect the sound waves, and a first mounting unit that positions the first actuator and the first sensor unit inside the tube.

[0007] One aspect of the present disclosure relates to a mute device for a wind instrument, and includes the detection device and a blocking device that is provided between the mouthpiece and the tube of the wind instrument and blocks air flowing from the mouthpiece into the tube.

[0008] A method for calculating a radiated sound waveform according to one aspect of the present disclosure estimates a tube shape model representing the tube shape of a wind instrument based on standing wave information regarding the distribution of standing waves generated within the tube of the wind instrument, and calculates a waveform related to the radiated sound from the wind instrument based on the estimated tube shape model and breath pressure information related to the breath pressure of the player playing the wind instrument.

[0009] A method for calculating a radiated sound waveform according to one aspect of the present disclosure estimates a tube shape model representing the tube shape of a wind instrument based on traveling wave information regarding the distribution of traveling waves generated within the tube of the wind instrument, and calculates a waveform related to the radiated sound from the wind instrument based on the estimated tube shape model and breath pressure information related to the breath pressure of the player playing the wind instrument.

[0010] A method for calculating a radiated sound waveform according to one aspect of the present disclosure estimates the shape of the oral cavity of a player playing a wind instrument having a manipulator based on vibration information related to the vibration of air in the oral cavity, and calculates a waveform related to the radiated sound from the wind instrument based on operation information indicating the player's operation of the manipulator, the estimated shape of the oral cavity, and breath pressure information related to the player's breath pressure. [Brief description of the drawings]

[0011] [Figure 1] 1 is a cross-sectional view taken along the central axis of a wind instrument mute device and a clarinet according to a first embodiment. [Diagram 2] 1 is a top view of a wind instrument mute device and a clarinet according to a first embodiment. FIG. [Diagram 3] 1 is a front view of a wind instrument mute device and a clarinet according to a first embodiment. FIG. [Figure 4] 1 is a block diagram showing an example of the configuration of a detection device of a wind instrument mute device according to a first embodiment; [Diagram 5] FIG. 2 is a diagram showing an example of a tone hole opening and closing pattern of the clarinet of FIG. 1. [Figure 6] FIG. 2 is a cross-sectional view showing the mouthpiece and reed of FIG. [Figure 7] FIG. 4 is a diagram showing the shape of a vibrating part of a reed. [Figure 8] FIG. 1 is an explanatory diagram of incident and reflected waves in a simple-shaped oral cavity. [Figure 9] FIG. 13 is an explanatory diagram of incident and reflected waves in a more complex shaped oral cavity. [Figure 10] FIG. 13 is a schematic explanatory diagram of incident, reflected, and transmitted waves in a more complex shaped oral cavity. [Figure 11] FIG. 2 is a block diagram showing a configuration of a physical model sound source unit. [Figure 12] FIG. 2 is a configuration diagram of a read dynamic characteristics block. [Figure 13] FIG. 11 is a block diagram showing an example of the configuration of a detection device according to a second embodiment. [Figure 14]FIG. 11 is a cross-sectional view showing a simple physical model according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] A: First embodiment A1: Configuration of a mute device for wind instruments

[0013] Fig. 1 is a cross-sectional view taken along the central axis of a wind instrument mute device and a clarinet according to the first embodiment. Fig. 2 is a top view of the wind instrument mute device and a clarinet according to the first embodiment. Fig. 3 is a front view of the wind instrument mute device and a clarinet according to the first embodiment. While Fig. 1 is a view of the wind instrument mute device and the clarinet seen from the horizontal direction, Fig. 2 is a view of the wind instrument mute device and the clarinet seen from above.

[0014] The wind instrument mute device 10 is attached between the mouthpiece 2 and the tube 3 of a clarinet 1, which is a wind instrument. In addition to the mouthpiece 2 and the tube 3, the clarinet 1 is equipped with a reed 4. In FIG. 1, the mouthpiece 2 is oriented so that the bottom surface of the mouthpiece 2 faces downward on the page.

[0015] A plurality of tone holes 5a-5e are opened in the tube 3 in the longitudinal direction of the tube 3. A plurality of operators 6a-6e are provided corresponding to the plurality of tone holes 5a-5e. The player can control the open / closed state of each of the tone holes 5a-5e by operating each of the operators 6a-6e. Note that while five tone holes and five operators are shown in FIG. 1 as a schematic, the number of tone holes and operators differs from that of an actual clarinet.

[0016] The mute device 10 for a wind instrument includes a detection device 20 and a blocking device 50.

[0017] The detection device 20 includes a first actuator 21 as a generating unit, a first sensor unit 31, a first mounting unit 41, a second actuator 22, a second sensor unit 32, a second mounting unit 42, a third actuator 23, a third sensor unit 33, a third mounting unit 43, a fourth sensor unit 34, and a fourth mounting unit 44.

[0018] The first mounting portion 41 disposes the first actuator 21 and the first sensor portion 31 inside the pipe 3. The first mounting portion 41 is a cylindrical member having one end in a flange shape, and extends in the longitudinal direction of the pipe 3. One end of the first mounting portion 41 is disposed near the inlet of the pipe 3. The other end of the first mounting portion 41 protrudes from the outlet of the pipe 3 to the outside of the pipe 3. The other end of the first mounting portion 41 is fixed to the pipe 3 via a fixing member 7. In FIG. 1, the first mounting portion 41 and the shutoff device 50 are formed as separate bodies, but the first mounting portion 41 and the shutoff device 50 may be formed integrally.

[0019] As shown in Fig. 3, the fixing member 7 has a center portion 71, three arms 72a, 72b, and 72c, and three hook portions 73a, 73b, and 73c. ​​The center portion 71 is attached to the other end of the first attachment portion 41. For example, as shown in Fig. 3, the center portion 71 is annular, and the other end of the first attachment portion 41 is fitted into the center portion 71.

[0020] The three arms 72a, 72b, and 72c extend radially from the center 71. The three arms 72a, 72b, and 72c are flexible. The three hooks 73a, 73b, and 73c are fixed to the ends of the three arms 72a, 72b, and 72c, respectively. The three hooks 73a, 73b, and 73c are hooked onto the ends of the pipe 3, respectively. This allows the other end of the first mounting part 41 to be fixed to the pipe 3 without wobbling. Therefore, the position of the first mounting part 41 relative to the pipe 3 is fixed. Note that the other end of the first mounting part 41 does not necessarily have to protrude from the pipe 3 as long as it is fixed to the pipe 3 without wobbling.

[0021] The first actuator 21 generates waves in the audible sound band that propagate inside the tube 3. Hereinafter, waves in the audible sound band will be referred to as sound waves. The first actuator 21 is provided on the flange portion 41a of the first attachment portion 41. The first actuator 21 is a speaker, a horn driver, a piezoelectric element, or the like. Therefore, the first actuator 21 generates sound waves and vibrates the air inside the tube 3. The first actuator 21 may be provided on the first attachment portion 41 in a portion near the outlet of the tube 3.

[0022] The first sensor unit 31 is provided on the cylindrical portion 41b of the first attachment portion 41. The first sensor unit 31 has eight sensors 31a, 31b, 31c, 31d, 31e, 31f, 31g, and 31h. Each of the eight sensors 31a to 31h is a microphone, a pressure transducer, or the like. Note that, although the first sensor unit 31 has eight sensors in FIG. 1, the number of sensors is not limited to this.

[0023] The eight sensors 31a-31h are arranged at intervals from one another in the longitudinal direction of the pipe 3. In particular, in this example, the eight sensors 31a-31h are arranged at equal intervals parallel to the central axis C1 of the pipe 3. The eight sensors 31a-31h are preferably arranged at intervals of 5-15 cm, but are not particularly limited to these values. Moreover, the sensors 31a-31h are preferably arranged along the central axis C1.

[0024] The second mounting portion 42 disposes the second actuator 22 and the second sensor portion 32 on the lead 4. The second mounting portion 42 has a first cantilever 42a and a second cantilever 42b. One end of the first cantilever 42a is fixed to the isolating device 50. The second actuator 22 is provided on the other end of the first cantilever 42a. The second actuator 22 is pressed against the lead 4 by the first cantilever 42a.

[0025] One end of the second cantilever 42b is fixed to the blocking device 50. The other end of the second cantilever 42b is provided with the second sensor portion 32. The second sensor portion 32 is pressed against the lead 4 by the second cantilever 42b.

[0026] The second actuator 22 vibrates the reed 4. The second actuator 22 is an actuator using a piezoelectric element. The second actuator 22 can displace the reed 4 by utilizing the inverse piezoelectric effect of the piezoelectric element. For example, when a sine wave voltage is applied to the piezoelectric element, the second actuator 22 can vibrate the reed 4 at the frequency of the sine wave.

[0027] The second actuator 22 generates vibrations having frequency components equal to or higher than the lowest pitch that can be produced by the clarinet 1. This vibration may be generated, for example, by applying to the piezoelectric element a voltage waveform that has been generated after passing a random noise waveform through a high-pass filter that reduces frequency components lower than the lowest pitch that can be produced by the clarinet 1. This vibration may also be generated by applying to the piezoelectric element a voltage waveform that is a sweep of a sine wave equal to or higher than the lowest pitch.

[0028] The second sensor unit 32 has one or more sensors and detects vibration of the lead 4. The second sensor unit 32 is a contact type vibration sensor. The second sensor unit 32 detects the displacement, displacement speed, and displacement acceleration of the lead 4. The vibration sensor is a sensor using a piezoelectric element. The vibration sensor converts the change in pressure caused by the vibration of the lead 4 into an electric signal by utilizing the piezoelectric effect of the piezoelectric element. The second sensor unit 32 may be configured with an acceleration sensor using MEMS (Micro Electro Mechanical Systems), an acceleration sensor using optical fiber, or the like. The vibration of the lead 4 may be detected not only by a contact type vibration sensor, but also by a non-contact type sensor. For example, the vibration of the lead 4 may be detected by a photocoupler.

[0029] The third attachment portion 43 disposes the third actuator 23 and the third sensor portion 33 within the mouthpiece 2 .

[0030] The third actuator 23 vibrates the air in the mouth of the player. The third actuator 23 is a speaker, a horn driver, a piezoelectric element, or the like.

[0031] The third sensor unit 33 detects vibration of the air in the mouth of the performer. The third sensor unit 33 is a microphone, a pressure transducer, or the like. The pressure transducer may be one that utilizes the resistance change of an isotropic conductor, or one that utilizes the piezoelectric effect of a piezoelectric element. The third sensor unit 33 may also be an acceleration sensor.

[0032] The fourth attachment portion 44 disposes the fourth sensor portion 34 within the mouthpiece 2. The fourth sensor portion 34 has one or more sensors. The fourth sensor portion 34 detects the breath pressure of the player and converts the detected breath pressure into an electrical signal. The converted electrical signal will hereinafter be referred to as a breath pressure signal. The fourth sensor portion 34 may be a gas pressure sensor, a wind speed sensor, a flow speed sensor, or the like.

[0033] The cutoff device 50 is provided between the mouthpiece 2 and the tube 3 of the clarinet 1. The cutoff device 50 is a cylindrical member. The cutoff device 50 has a main body 50a, a small diameter portion 50b, and an annular portion 50c. The outer diameter of the small diameter portion 50b is the same as or smaller than the inner diameter of the tube 3. The small diameter portion 50b fits into the tube 3. The annular portion 50c is annular, and the inner diameter of the annular portion 50c is the same as or smaller than the outer diameter of the mouthpiece 2. The annular portion 50c fits into the mouthpiece 2. The cutoff device 50 is composed of the main body 50a, the small diameter portion 50b, and the annular portion 50c, but this is a configuration suitable for the shape of the clarinet 1, and is not necessarily suitable for all other reed instruments. The shape of the cutoff device 50 is appropriately changed according to the shape of the reed instrument.

[0034] The cutoff device 50 and the first attachment portion 41 are joined at the surface of the cutoff device 50 facing the tube 3, i.e., between the bottom surface of the small diameter portion 50b and the end surface of the flange portion 41a of the first attachment portion 41. An inner wall surface 50d of the cutoff device 50 and an inner wall surface 41c of the first attachment portion 41 are continuous without any step. The cutoff device 50 cuts off air flowing from the mouthpiece 2 into the tube 3. In other words, the space inside the mouthpiece 2 and the space inside the tube 3 are not connected.

[0035] On the other hand, the space inside the mouthpiece 2 and the space inside the first attachment part 41 are in communication. As described above, the space inside the first attachment part 41 is formed by the inner wall surface 41c. Therefore, the air flowing in from the mouthpiece 2 passes through the inside of the first attachment part 41 and is discharged to the outside from the end of the first attachment part 41. Therefore, even if the player of the clarinet 1 blows into the mouthpiece 2, the blown breath does not flow into the tube 3, so the player's breath does not contribute to the generation of air vibrations in the tube 3. Therefore, the wind instrument mute device 10 functions as a mute device for the clarinet 1. Note that the main body part 50a may have an air vent hole. If the main body part 50a has an air vent hole, even if the player blows into the mouthpiece 2, the blown breath flows out from the air vent hole and does not flow into the tube 3. Also, if the main body part 50a has an air vent hole, the space inside the first attachment part 41 may not be provided.

[0036] A2: Configuration of the detection device Hereinafter, the configuration of the detection device of the wind instrument mute device 10 according to the first embodiment will be described with reference to FIG.

[0037] 4 is a block diagram showing an example of the configuration of a detection device of the wind instrument mute device 10 according to the first embodiment. The detection device 20 includes a first actuator 21, a second actuator 22, a third actuator 23, a first sensor section 31, a second sensor section 32, a third sensor section 33, a fourth sensor section 34, a storage device 80, and a processing device 90.

[0038] The storage device 80 is a recording medium readable by a computer (for example, a non-transitive recording medium readable by a computer). The storage device 80 includes a non-volatile memory and a volatile memory. The non-volatile memory is, for example, a Read Only Memory (ROM), an Erasable Programmable Read Only Memory (EPROM), and an Electrically Erasable Programmable Read Only Memory (EEPROM). The volatile memory is, for example, a Random Access Memory (RAM).

[0039] The storage device 80 stores a program p1 and various information. The program p1 defines the operation of the detection device 20. The storage device 80 may store the program p1 read from a storage device in a server (not shown). In this case, the storage device in the server is an example of a computer-readable recording medium.

[0040] The processing device 90 includes one or more central processing units (CPUs). The one or more CPUs are an example of one or more processors. Each of the processing device, the processor, and the CPU is an example of a computer.

[0041] The processing device 90 reads a program p1 from the storage device 80. The processing device 90 executes the program p1 to function as a control unit 91, a first signal processing unit 92, a pattern estimation unit 92a, a tube shape model estimation unit 92b, a second signal processing unit 93, a third signal processing unit 94, a fourth signal processing unit 95, and a physical model sound source unit 96. At least one of the control unit 91, the first signal processing unit 92, the pattern estimation unit 92a, the tube shape model estimation unit 92b, the second signal processing unit 93, the third signal processing unit 94, the fourth signal processing unit 95, and the physical model sound source unit 96 may be realized by a circuit such as a DSP (Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), or an FPGA (Field Programmable Gate Array).

[0042] The control unit 91 controls the first actuator 21, the second actuator 22, and the third actuator 23.

[0043] The first signal processing unit 92 is composed of an amplifier circuit and a sample-and-hold circuit. The first signal processing unit 92 acquires detection signals output from the eight sensors 31a to 31h of the first sensor unit 31 during the period when the first actuator 21 is in operation. The first signal processing unit 92 extracts standing wave information, which is information on the distribution of standing waves generated in the tube 3, based on the acquired detection signals, and outputs the extracted standing wave information. Note that, during the operation period of the first actuator 21, a sinusoidal sweep waveform in the audible sound band may be input to the first actuator 21. Also, the sweep waveform may be provided to the first actuator 21 in semitone increments.

[0044] The standing wave information is extracted as follows. First, the control unit 91 vibrates the first actuator 21 with a frequency in the audible range. When the vibration of the first actuator 21 vibrates the air inside the tube 3, a standing wave is generated inside the tube 3 according to the open / closed state of the sound holes 5a-5e. The standing wave is a composite wave of a progressive wave and a backward wave. The progressive wave is a wave that travels from the entrance of the tube 3 to the exit of the tube 3, and the backward wave is a wave that travels from the exit of the tube 3 to the entrance of the tube 3 as a result of the progressive wave being reflected at the exit of the tube 3.

[0045] Each of the sensors 31a-31h detects the sound pressure of a standing wave at the point where the sensor 31a-31h is located, and outputs the detected sound pressure. Each of the sensors 31a-31h detects the superposition of a forward wave and a backward wave as a standing wave. When each of the sensors 31a-31h is a microphone, each of the sensors 31a-31h outputs a sound pressure level according to the detected amplitude intensity. The output sound pressure level from each of the sensors 31a-31h changes in a sinusoidal wave shape, but the change pattern of each output sound pressure level differs depending on the position of each of the sensors 31a-31h.

[0046] The amplitude of the sound pressure detected by a sensor located at the antinode of the standing wave is maximum, and the amplitude of the sound pressure detected by a sensor located at the node of the standing wave is minimum. The distribution of the amplitude of the change in each output sound pressure level within the pipe 3 corresponds to the sound pressure distribution of the standing wave generated within the pipe 3.

[0047] Therefore, the first signal processing unit 92 acquires each output sound pressure level that changes in a sinusoidal manner from each of the sensors 31a to 31h. The first signal processing unit 92 amplifies each acquired output sound pressure level in an amplifier circuit. The first signal processing unit 92 detects a peak value of each amplified output sound pressure level from each amplified output sound pressure level using a sample-and-hold circuit.

[0048] Each detected peak value indicates the sound pressure distribution of the standing wave at each sensor position. Therefore, the first signal processing unit 92 can estimate the sound pressure distribution of the standing wave in the pipe 3 based on the amplitude of the sound pressure level detected by each sensor. The first signal processing unit 92 outputs amplitude information of the sound pressure level at each sensor 31a-31h to the pattern estimation unit 92a. In this way, the standing wave information is based on information output from the multiple sensors 31a-31h.

[0049] The pattern estimation unit 92a estimates the sound hole opening and closing pattern based on the amplitude information of the sound pressure levels in the sensors 31a to 31h.

[0050] FIG. 5 is a diagram showing an example of a tone hole opening and closing pattern of the clarinet 1 of FIG. 1. In FIG. 5, a specific pitch i (i=1, 2, . . . , N) of the clarinet 1 is associated with the open / closed state of each tone hole of the clarinet 1. The tone hole numbers are assigned in order according to the distance from the outlet of the tube 3, with the tone hole closest to the outlet of the tube 3 being number 1 and the tone hole furthest from the outlet of the tube 3 being number 24. The open / closed state of each tone hole is represented by 0 or 1. Here, "0" represents a state in which the tone hole is closed, and "1" represents a state in which the tone hole is open. The pattern in which the open / closed states of each tone hole are arranged in the order of the tone hole numbers is the tone hole opening and closing pattern of the clarinet 1, and the tone hole opening and closing pattern at a specific pitch i is called OCP(i). The tone hole opening and closing pattern OCP(i) is a discrete value.

[0051] According to FIG. 5, the tone hole opening and closing pattern OCP(1) is a value for the pitch "E3." When the pitch "E3" is produced, all tone holes are closed, so the tone hole opening and closing pattern OCP(1) has values ​​of "0" corresponding to all tone hole numbers. The tone hole opening and closing pattern OCP(i) is a value for the pitch "F#3." When the pitch "F#3" is produced, the tone hole opening and closing pattern OCP(i) has values ​​of "1" corresponding to tone hole numbers 1 and 2, and values ​​of "0" corresponding to tone hole numbers 3 to 24.

[0052] The tone hole opening and closing pattern OCP(i) is information regarding the opening and closing status of each of the multiple tone holes of the clarinet 1. Therefore, the tone hole opening and closing pattern OCP(i) can also be said to be information regarding the fingering status of the player of the clarinet 1. Below, a machine learning method using a classification method for the tone hole opening and closing pattern OCP(i) will be described.

[0053] In this embodiment, learning is performed using a support vector machine as supervised learning by a classification method. Input data to the support vector machine is acquired as follows. When fingering corresponding to each tone hole opening and closing pattern OCP(i) is being performed on the clarinet 1, white noise is input to the first sensor unit 31 for a certain period of time. The white noise input to the first sensor unit 31 may be generated, for example, from the first actuator 21, or from another actuator, a speaker, or the like. If the multiple sensors of the first sensor unit 31 are composed of m microphones, the output sound pressure levels of the m microphones are time-averaged. The time average of each output sound pressure level is tried a total of n times for each tone hole opening and closing pattern.

[0054] The output sound pressure level of the first microphone, the output sound pressure level of the second microphone, ..., and the output sound pressure level of the m microphone in the first trial are represented as L1(1) decibels, L2(1) decibels, ..., and Lm(1) decibels, respectively. The output sound pressure level of the first microphone, the output sound pressure level of the second microphone, ..., and the output sound pressure level of the m microphone in the nth trial are represented as L1(n) decibels, L2(n) decibels, ..., and Lm(n) decibels, respectively.

[0055] The first trial result, I1(L1(1),L2(1),...,Lm(1)), the second trial result, I2(L1(2),L2(2),...,Lm(2)),..., and the nth trial result, In(L1(n),L2(n),...,Lm(n)), are given as input data to the support vector machine. Hereinafter, I1, I2,...,In are referred to as standing wave sound pressure distribution information. In addition, the sound hole opening and closing pattern OCP(i) is given as output data of the support vector machine.

[0056] A machine learning device for a support vector machine model inputs standing wave sound pressure distribution information I1-In as input data into a support vector machine model, and trains the support vector machine model on the correlation between the standing wave sound pressure distribution information I1-In as input data and the sound hole opening and closing pattern OCP(i) as output data.

[0057] When the machine learning device determines that a predetermined training end condition is satisfied, it ends the training and stores the support vector machine model at that point as a trained model in the storage device 80. The predetermined training end condition is, for example, that the number of iterations of the series of training processes reaches a predetermined number.

[0058] In this way, the relationship between the combination of the output sound pressure levels of the m microphones and the sound hole opening and closing pattern OCP(i) is learned.

[0059] The pattern estimation unit 92a outputs the estimated sound hole opening and closing pattern to the tube shape model estimation unit 92b. The pattern estimation unit 92a has a trained support vector machine. Therefore, when the amplitude information of the sine wave signal in each sensor of the first sensor unit 31, i.e., the combination of the output sound pressure levels in each sensor, is input, the pattern estimation unit 92a predicts the corresponding sound hole opening and closing pattern OCP(i).

[0060] The tube shape model estimation unit 92b receives the estimated sound hole opening and closing pattern from the pattern estimation unit 92a. The tube shape model estimation unit 92b refers to the sound hole opening and closing pattern database 81, and estimates a tube shape model based on the input sound hole opening and closing pattern and the sound hole opening and closing pattern database 81. The tube shape model estimation unit 92b outputs the estimated tube shape model to the physical model sound source unit 96.

[0061] The second signal processing unit 93 calculates reed resonance characteristic information based on the vibration information of the reed 4 input from the second sensor unit 32, and outputs the information to the physical model sound source unit 96. More specifically, the control unit 91 operates the second actuator 22, which vibrates the reed 4, and the second signal processing unit 93 acquires a waveform related to the displacement of the reed 4 from the second sensor unit 32 as the vibration information of the reed 4. In this way, the second signal processing unit 93 can also be said to be a reed state estimation unit that estimates the change state of the shape of the reed 4 based on the detection result by the second sensor unit 32.

[0062] FIG. 6 is a cross-sectional view showing the mouthpiece 2 and the reed 4. FIG. 7 is a diagram showing the shape of the vibrating part of the reed 4. As shown in FIG. 6, the x-axis is an axis passing through the origin O when the tip of the mouthpiece 2 is set as the origin O, and is parallel to the axis of the mouthpiece 2. That is, the x-axis is an axis parallel to the central axis C1 of the tube 3 when the mouthpiece 2 and the tube 3 are connected. The y-axis is an axis passing through the origin O and along the direction of the tip opening. That is, the x-axis and the y-axis are perpendicular to each other. The positive direction of the y-axis is downward in FIG. 6, that is, the direction in which the reed 4 moves away from the mouthpiece 2 when the reed 4 vibrates.

[0063] In Figure 7, l r is the effective vibration length of the reed 4, that is, the length of the portion of the reed 4 that actually contributes to vibration. b is the width of the tip of the reed 4. In FIG. ext is the external force in the y direction that the player applies to the reed 4 through the player's lips. H is the external force F extis 0. y0 is the y coordinate value of the tip of the lead 4 when the external force F ext is applied to the reed 4. In other words, y0 indicates the static opening degree of the reed 4. S1 is the area of ​​the gap between the reed 4 and the mouthpiece 2. Hereinafter, S1 will be referred to as the reed gap area.

[0064] m r is the effective vibrating mass of the reed 4, i.e., the mass of the part of the reed 4 that vibrates. In the following, m r is called the reed effective seismic mass. S r is the effective vibration area of ​​the lead 4. r is called the effective reed vibration area. r is the effective mass of the lead 4 per unit area. r is called the lead unit effective mass. H is the external force F ext is 0. In other words, H is the initial value of the static opening degree of the lead 4.

[0065] The second signal processing unit 93 calculates the lead resonance characteristic based on the acquired waveform related to the displacement of the lead 4 along the y-axis, and outputs it as lead resonance characteristic information. The lead resonance characteristic information includes the resonant frequency f r and the opening y0 of lead 4 along the y axis.

[0066] The second signal processing unit 93 also passes the acquired waveform relating to the displacement of the lead 4 along the y-axis through an LPF to calculate the static displacement of the lead 4 at the contact position between the lead 4 and the second sensor unit 32. Furthermore, the second signal processing unit 93 calculates the opening degree y0 of the tip portion of the lead 4 based on the static displacement at the contact position between the lead 4 and the second sensor unit 32.

[0067] The displacement of the tip of the lead 4 may be detected using a photocoupler. In this case, the static opening of the lead tip may be obtained by applying a low-pass filter to the detection signal of the photocoupler. This allows the displacement of the tip of the lead 4 to be detected more accurately.

[0068] The third signal processing unit 94 estimates the shape of the performer's oral cavity in real time based on the reflected waves reflected in the oral cavity of the performer, and outputs information on the estimated oral cavity shape as oral cavity shape information to the physical model sound source unit 96. In this way, the third signal processing unit 94 can also be said to be an oral cavity shape estimation unit that estimates the shape of the oral cavity based on the detection result by the third sensor unit 33.

[0069] More specifically, when the player holds the mouthpiece 2 in his / her mouth and the control unit 91 vibrates the third actuator 23, the third signal processing unit 94 acquires from the third sensor unit 33 a sound pressure signal detected by the third sensor unit 33. At this time, the sound pressure signal acquired by the third signal processing unit 94 includes a signal due to a reflected wave reflected in the mouth and airway of the player.

[0070] For example, the Ware and Aki algorithm is used as a method for estimating the oral cavity shape in real time in the third signal processing unit 94. Since the oral cavity and the airway are continuous, the oral cavity shape estimated by the above algorithm also includes the airway shape.

[0071] Fig. 8 is an explanatory diagram of incident and reflected waves in a simple-shaped oral cavity. In the oral cavity shown in Fig. 8, the cross-sectional area of ​​the oral cavity changes stepwise from the inlet cross-sectional area A0 to the first cross-sectional area A1 at a position x0 from the oral cavity entrance. Under the condition that the pressure and volumetric flow rate are conserved even at the change point of the cross-sectional area, i.e., the discontinuous point, the reflection coefficient r of sound is expressed as the ratio of the incident wave to the reflected wave P i , the reflected wave is P r This can be calculated as shown in the following equation (1).

[0072] r=(P r / P i ) × (A0-A1) / (A0+A1) (1)

[0073] Here, since the inlet cross-sectional area A0 is known, the first cross-sectional area A1 inside the oral cavity is calculated according to the following formula (2).

[0074] A1=[(P r -r×P i ) / (P r +r×P i )] × A0 (2)

[0075] Fig. 9 is an explanatory diagram of incident waves and reflected waves in an oral cavity with a more complicated shape. In the oral cavity shown in Fig. 8, the cross-sectional areas of the oral cavity at positions x0, 2x0, 3x0, and 4x0 from the entrance of the oral cavity are A0, A1, A2, and A3, respectively. Fig. 10 is a schematic explanatory diagram of incident waves, reflected waves, and transmitted waves in an oral cavity with a more complicated shape. An incident wave P i is incident, a reflected wave P(T) reflected by the cross section at position x0 is observed at time T, and a reflected wave P(2T) reflected by the cross section at time 2T and position 2x0 is observed.

[0076] Here, by using equation (2), the first cross-sectional area A1 and the second cross-sectional area A2 are calculated. At time 3T, a mixed wave of the reflected wave Pr1 from the cross section at position 3x0 and the multiple reflected wave Pr2 shown by the dashed line is observed. Since the multiple reflected wave Pr2 is calculated from the entrance cross-sectional area A0, the first cross-sectional area A1, and the second cross-sectional area A2, the component of the multiple reflected wave Pr2 can be removed from the mixed wave. Therefore, since the reflected wave Pr1 is separated from the mixed wave, the third cross-sectional area A3 can be calculated from equation (2). In the Ware and Aki algorithm, the oral cavity shape is estimated taking into account the effect of such multiple reflections.

[0077] The fourth signal processing unit 95 acquires from the fourth sensor unit 34 a breath pressure signal detected by the fourth sensor unit 34. The fourth signal processing unit 95 extracts information related to breath pressure based on the acquired breath pressure signal, and outputs the extracted information related to breath pressure as breath pressure information to the physical model sound source unit 96. In this way, the fourth signal processing unit 95 can also be said to be a breath pressure information generating unit that generates breath pressure information based on the detection result by the fourth sensor unit 34.

[0078] More specifically, the signal generated by the second actuator 22, the signal generated by the third actuator 23, and the signal generated from the mouth of the performer are superimposed on the signal detected by the fourth sensor unit 34. The signals generated by the second actuator 22 and the third actuator 23 are mainly signals of frequencies in the audible range, but the signal related to the breath pressure generated from the mouth of the performer is a signal having frequency components lower than the frequencies in the audible range.

[0079] To separate the signal detected by the second actuator 22 from the signal detected by the fourth sensor unit 34, the second actuator 22 may vibrate the reed 4 with a small amplitude so as not to interfere with air vibrations. To separate the signal detected by the third actuator 23 from the signal detected by the fourth sensor unit 34, a low-pass filter may be used. Therefore, the signal related to breath pressure is separated from the signal generated by the second actuator 22 and the signal generated by the third actuator 23 by vibrating the reed 4 with a small amplitude by the second actuator 22 and using a low-pass filter. This makes it possible to extract a breath pressure signal that is not affected by resonance in the oral cavity.

[0080] The fourth signal processing unit 95 can extract only the breath pressure information by passing the acquired breath pressure signal through a low-pass filter.

[0081] The physical model sound source unit 96 calculates a radiated sound waveform based on the output signal from the tubular body shape model estimation unit 92b, the output signal from the second signal processing unit 93, the output signal from the third signal processing unit 94, and the output signal from the fourth signal processing unit 95. The radiated sound waveform output from the physical model sound source unit 96 is output to the amplifier AM and amplified in the amplifier AM. The radiated sound waveform amplified in the amplifier AM is output to the speaker SP and converted into a sound signal in the speaker SP. Note that headphones, earphones, etc. may be used instead of the speaker SP. The configuration and operation of the physical model sound source unit 96 will be described below with reference to Figs. 11 and 12.

[0082] Fig. 11 is a block diagram showing the configuration of the physical model sound source unit 96. As shown in Fig. 11, the physical model sound source unit 96 has a reed dynamic characteristics block 961, a tube propagation realization block 962, an oral cavity propagation realization block 963, and a radial propagation realization block 964.

[0083] Fig. 12 is a configuration diagram of a lead dynamic characteristics block 961. The lead dynamic characteristics block 961 includes a model related to the dynamic characteristics of a single lead. As shown in Fig. 12, the lead dynamic characteristics block 961 includes a subtraction unit 961a, an inversion unit 961b, a lead dynamic characteristics filter unit 961c, a first calculation unit 961d, a constant multiplication unit 961e, a second calculation unit 961f, and a multiplication unit 961g.

[0084] The reed dynamics block 961 receives the breath pressure signal p0(t) and the pressure signal p(t) immediately below the reed 4. The subtractor 961a subtracts the pressure signal p(t) immediately below the reed 4 from the breath pressure signal p0(t) and outputs Δp(t) which is the difference between the breath pressure signal p0(t) and the pressure signal p(t) immediately below the reed 4. The difference value Δp(t) is input to the inverter 961b and the second calculator 961f. The output signal from the inverter 961b is input to the reed dynamics filter 961c. The breath pressure signal acquired by the fourth signal processor 95 is associated with p0 input to the oral cavity side waveguide model. In the case of a configuration without an oral cavity propagation realization block, the breath pressure signal acquired by the fourth signal processor 95 is associated with the breath pressure signal p0(t) input to the reed dynamics block 961.

[0085] The reed dynamic characteristic filter section 961c further includes a resonant frequency f r , Q factor Q r , lead unit effective mass μ r , the static opening degree y0 of the lead 4, and the initial value H of the static opening degree of the lead 4. The lead dynamic characteristic filter unit 961c is r , Q factor Q r , lead unit effective mass μ r , the static opening y0 of the lead 4, and an initial value H of the static opening of the lead 4 as parameters. In this example, a second-order IIR filter (Infinite Impulse Response Filter) is used as the digital filter.

[0086] The output y of the reed dynamic characteristic filter section 961c is y0 when the difference value Δp(t) is 0, and decreases monotonically as the breath pressure signal p0(t) increases.

[0087] The output y of the lead dynamic characteristic filter unit 961c is input to the first calculation unit 961d. The first calculation unit 961d outputs an output G(y) as a calculation result. The output G(y) is a function that limits the displacement of the lead 4. The output G(y) is an output in which the displacement along the y axis in the area where the difference value Δp(t) indicates a negative value is limited. Furthermore, the output G(y) clips values ​​in the area where the y coordinate value is negative to 0. In other words, the output G(y) limits the y value to a value equal to or greater than 0.

[0088] The output G(y) is input to a constant multiplication unit 961e. The constant multiplication unit 961e multiplies the output G(y) by b. This calculation corresponds to calculating the area S1 of the gap between the reed 4 and the mouthpiece 2. The coefficient b corresponds to the width of the tip of the reed 4.

[0089] The second calculation unit 961f calculates and outputs the flow velocity u of the air in the gap between the reed 4 and the mouthpiece 2 according to the following equation (3).

[0090] u = (2 × Δp(t) / ρ) 1 / 2 (3)

[0091] The multiplication unit 961g multiplies the area S1 of the gap between the reed 4 and the mouthpiece 2 by the flow velocity u, and outputs the multiplication result as the volumetric flow velocity U(t) in the gap between the reed 4 and the mouthpiece 2.

[0092] 11 again, the tube propagation realization block 962 has a tube side waveguide model 962a. The tube shape information estimated by the tube shape model estimator 92b is input to the tube side waveguide model 962a. This forms a tube side waveguide model. The volume flow velocity U(t) in the gap between the reed 4 and the mouthpiece 2 is input to the tube propagation realization block 962 from the reed dynamics block 961. The tube propagation realization block 962 outputs a pressure signal p(t) directly below the reed 4 to the reed dynamics block 961. The transfer function Z of the tube propagation realization block 962 is in (f) is expressed as p(f) / U(f).

[0093] In addition, the tube-side waveguide model 962a calculates the sound pressure signal p out (t) is output to the radial propagation realization block 964.

[0094] The oral cavity propagation realization block 963 has an oral cavity side waveguide model 963a. Oral cavity shape information estimated in the third signal processing unit 94 is input to the oral cavity side waveguide model 963a. In this way, an oral cavity side waveguide model is formed. The oral cavity propagation realization block 963 receives a volume flow velocity U(t) from the reed dynamics block 961. The oral cavity propagation realization block 963 outputs a breath pressure signal p0(t) to the reed dynamics block 961.

[0095] The radiation propagation realization block 964 includes a sound pressure signal p out (t) is input. The radiation propagation realization block 964 calculates the sound pressure signal p out Based on (t), the radiated sound pressure signal p rad (t). The radial propagation realization block 964 is realized, for example, by an IIR filter.

[0096] In this way, the processing device 90 estimates a tube shape model based on the tone hole opening and closing pattern estimated by the pattern estimation unit 92a, and calculates a waveform related to the sound emitted from the clarinet 1 based on the estimated tube shape model, the estimated changes in the shape and characteristics of the reed 4, the estimated shape of the oral cavity, and the generated breath pressure information. With this configuration, the physical model sound source unit 96 can handle changes in tone color due to embouchure including bending, flaxen playing, etc. The processing device 90 estimates whether bending is being performed based on the distortion of the reed 4, and estimates whether flaxen playing is being performed based on the shape of the player's oral cavity.

[0097] A3: Summary of the first embodiment As described above, detection device 20 according to the first embodiment includes first actuator 21 and first sensor section 31. First actuator 21 generates sound waves that propagate within the tube 3 of clarinet 1. First sensor section 31 has a number of sensors 31a-31h that detect the sound waves. First actuator 21 and first sensor section 31 are disposed within the tube 3. The multiple sensors 31a-31h are disposed at intervals from one another in the longitudinal direction of tube 3.

[0098] According to the detection device 20 of the first embodiment, by having a plurality of sensors 31a to 31h, it is possible to detect the distribution of standing waves related to the sound pressure generated in the tube 3, and from the distribution of the standing waves, it is possible to estimate the open / closed state of each of the plurality of sound holes, that is, the sound hole opening / closing pattern. Therefore, according to the detection device 20 of the first embodiment, it is possible to more accurately detect the playing state of the clarinet 1. More specifically, by estimating the sound hole opening / closing pattern, it is possible to obtain parameters necessary for accurately calculating the radiated sound waveform of the clarinet 1. For example, even if the frequency of the sound produced is the same, it is possible to identify a playing style that results in fingering that has a different sound hole opening / closing pattern. In addition, since each of the plurality of sensors 31a to 31h is arranged at intervals from each other in the longitudinal direction of the tube 3, it is possible to more accurately detect the standing waves generated in the tube 3. Therefore, it is possible to more accurately estimate the sound hole opening / closing pattern.

[0099] In the first embodiment, the clarinet 1 is an example of a "wind instrument", and the first actuator 21 is an example of a "generator".

[0100] The detection device 20 further includes a second actuator 22 and a second sensor unit 32. The second actuator 22 vibrates the reed 4 of the clarinet 1. The second sensor unit 32 has a sensor that detects the vibration of the reed 4. The second actuator 22 and the second sensor unit 32 are disposed on the reed 4.

[0101] This makes it possible to detect the resonance characteristics and static opening of the reed 4, and therefore, even if the tone hole opening and closing pattern is the same, it is possible to accommodate playing styles that produce different pitches or timbres due to the resonance characteristics and static opening of the reed 4. As a result, the playing state of the clarinet 1 can be detected more accurately.

[0102] The detection device 20 further includes a third actuator 23 and a third sensor unit 33. The third actuator 23 vibrates the air in the mouth of the player playing the clarinet 1. The third sensor unit 33 has a sensor that detects the vibration of the air in the mouth. The third actuator 23 and the third sensor unit 33 are disposed in the mouthpiece 2 of the clarinet 1.

[0103] This allows the shape of the player's mouth to be detected, so that the playing state of the clarinet 1 can be detected more accurately.

[0104] Moreover, the detection device 20 further includes a fourth sensor unit 34. The fourth sensor unit 34 has a sensor that detects the breath pressure of a player playing the clarinet 1. The fourth sensor unit 34 is disposed within the mouthpiece 2 of the clarinet 1.

[0105] This makes it possible to detect the breath pressure of the player, thereby making it possible to detect the playing state of the clarinet 1 more accurately.

[0106] The generator generates sound waves by vibrating the air in the tube 3 of the clarinet 1. The first actuator 21 generates sound waves by vibrating the air in the tube 3 of the clarinet 1.

[0107] According to this, sound waves propagating within pipe 3 are detected by a plurality of sensors 31a-31h spaced apart from one another in the longitudinal direction of pipe 3. Since sound waves propagating within pipe 3 appear as standing waves, each of sensors 31a-31h can detect a sound pressure level according to the sound pressure distribution of the standing waves within pipe 3. The sound pressure distribution of the standing waves can be estimated from the detection results of the sound pressure levels by each of sensors 31a-31h.

[0108] The detection device 20 according to the first embodiment includes a first actuator 21 and a first sensor unit 31. The first actuator 21 and the first sensor unit 31 are disposed inside the tube 3. The first actuator 21 generates sound waves by vibrating the air inside the tube 3 of the clarinet 1. The first sensor unit 31 has a number of sensors 31a-31h that detect sound waves.

[0109] Sound waves propagating inside the pipe appear as standing waves, and in order to detect the sound pressure distribution of the standing waves, it is preferable to detect the sound waves at a position close to the central axis C1 of the pipe 3. In this way, since multiple sensors 31a-31h are disposed inside the pipe 3, even if the position of the first attachment part is shifted, a sensor close to the central axis C1 of the pipe can be selectively used, and the sound pressure distribution of the standing waves can be detected more accurately.

[0110] Moreover, the sensors 31a to 31h are arranged in the longitudinal direction of the pipe 3 at intervals from one another.

[0111] According to this, since each of the plurality of sensors 31a to 31h is arranged at intervals from one another in the longitudinal direction of the pipe 3, the sound pressure distribution of the standing waves generated within the pipe 3 can be detected more accurately.

[0112] The mute device 10 for a wind instrument according to the first embodiment includes a detection device 20 and a cutoff device 50. The cutoff device 50 is provided between a mouthpiece 2 and a tube 3 of a clarinet 1. The cutoff device 50 cuts off air flowing from the mouthpiece 2 into the tube 3.

[0113] According to this, the space inside the tube 3 is not connected to the space inside the blocking device 50 that blocks the air flowing into the tube 3 from the mouthpiece 2. Therefore, the air blown by the player into the mouthpiece 2 does not flow into the tube 3. As a result, the clarinet 1 is muted.

[0114] The method for calculating a radiated sound waveform according to the first embodiment estimates a tube shape model based on standing wave information, and calculates a waveform related to the radiated sound from the clarinet 1 based on the estimated tube shape model and breath pressure information. The standing wave information is information related to the distribution of standing waves generated within the tube 3 of the clarinet 1. The tube shape model is a model that indicates the tube shape of the clarinet 1. The breath pressure information is information related to the breath pressure of the performer playing the clarinet 1.

[0115] According to this, a tube shape model is determined from the detected standing waves. The tube shape model is a model that estimates pitch information and timbre information from the tube shape according to the player's fingering on the clarinet 1, so a sound waveform that more accurately reproduces the playing state of the clarinet 1 is calculated. Furthermore, according to the above aspect, breath pressure information is generated based on the detected breath pressure of the player, so a sound waveform that matches the playing timing, strength of breath pressure, etc. of the player can be calculated based on the breath pressure information.

[0116] Moreover, estimating the tube shape model includes inputting standing wave information and outputting a tone hole opening and closing pattern for the clarinet 1, and determining the tube shape model based on the output tone hole opening and closing pattern. The tone hole opening and closing pattern is a pattern that indicates a combination of the open and closed states of each of a plurality of tone holes.

[0117] According to this, a tone hole opening and closing pattern is estimated from the detected standing waves, and a tube shape model is determined based on the estimated tone hole opening and closing pattern. Since the tube shape model is a model that estimates pitch information and timbre information from the tube shape according to the player's fingering on clarinet 1, a waveform that more accurately reproduces the playing state of clarinet 1 can be calculated.

[0118] Furthermore, the frequency of the standing wave is included in the audible sound band.

[0119] According to this, waves in the audible sound band, i.e., sound waves, are less likely to attenuate within the tube 3 and are more likely to appear as standing waves. Therefore, the tone hole opening and closing pattern can be estimated by generating sound waves within the tube 3 and detecting the standing waves with multiple sensors. Furthermore, since the audible sound band is the same as the sound production band of the clarinet 1, the tone hole opening and closing pattern can be easily estimated.

[0120] In addition, the method for calculating the radiated sound waveform in the first embodiment estimates the state of change in the shape of the reed 4 based on the reed vibration information, and calculates a waveform related to the radiated sound based on the estimated tubular shape model, the estimated state of change in the shape of the reed 4, and the generated breath pressure information. The reed vibration information is information relating to the vibration of the reed 4 of the clarinet 1.

[0121] According to this, the resonance characteristics of the reed 4 and the static opening of the reed 4 are estimated from the detected vibration information. Therefore, since it is possible to reflect whether or not the performer is performing a bend technique, a sound waveform that more accurately reproduces the performance state of the clarinet 1 can be calculated.

[0122] Furthermore, the method for calculating a radiated sound waveform according to the first embodiment estimates a tubular shape model using a trained model in which the correlation between the standing wave sound pressure distribution information and the sound hole opening and closing pattern OCP(i) is trained.

[0123] According to this, when the standing wave sound pressure distribution information is input to the trained model, the sound hole opening and closing pattern OCP(i) corresponding to the standing wave sound pressure distribution information is output, and the tube shape model is estimated from the sound hole opening and closing pattern OCP(i) output from the trained model. Therefore, since there is no need to develop a complex program for estimating the sound hole opening and closing pattern OCP(i) from the standing wave sound pressure distribution information, the tube shape model is easily estimated. Note that the standing wave sound pressure distribution information is an example of "standing wave information".

[0124] Furthermore, the method for calculating a radiated sound waveform according to the first embodiment estimates the shape inside the oral cavity based on vibration information, and calculates a waveform related to the radiated sound from the clarinet 1 based on operation information, the estimated shape inside the oral cavity, and breath pressure information. The vibration information is information related to the vibration of air inside the oral cavity of a player playing the clarinet 1 having the controls 6a to 6e. The operation information is information indicating the player's operation of the controls. The breath pressure information is information related to the breath pressure of the player.

[0125] According to this, the shape of the mouth of the player is estimated based on the detected vibration of the air in the mouth. Therefore, it is possible to reflect the state of the player's embouchure and whether or not the player is using the flute technique, so that a sound waveform that more accurately reproduces the playing state of the clarinet 1 can be calculated. The flute technique is a playing style that can produce different pitches due to the resonance characteristics of the mouth caused by different mouth shapes, even if the tone hole opening and closing patterns are the same.

[0126] Moreover, the method for calculating a radiated sound waveform according to the first embodiment outputs a waveform relating to the radiated sound as an electrical signal.

[0127] According to this, a sound waveform that reproduces the performance state of the clarinet 1 is output as an electrical signal, so that the performer can listen to the reproduced performance using a speaker SP, headphones, etc.

[0128] In this embodiment, the sound pressure distribution of the standing wave is observed and the sound hole opening and closing pattern is estimated from the sound pressure distribution of the standing wave, but it is also possible to observe the density distribution of ultrasonic or electromagnetic standing waves instead of sound waves and estimate the sound hole opening and closing pattern from this. It is difficult for ultrasonic or electromagnetic standing waves to be generated inside the tube 3. However, it is possible to observe the density distribution of the standing wave by installing a reflector at the bell outlet, for example, and generating a reflected wave by the reflector. Therefore, in the case of ultrasonic or electromagnetic waves, a reflector may be installed.

[0129] Furthermore, there may be multiple reflectors inside the tube 3. In the case of electromagnetic waves, each of the multiple reflectors is preferably made of metal. In the case of ultrasonic waves, each of the multiple reflectors is preferably circular, and the material of each reflector is not particularly limited. The installation position of each of the multiple reflectors is preferably immediately behind each sound hole. In this case, the installation positions of the multiple sensors are preferably immediately before and immediately after each sound hole.

[0130] Here, "just before each sound hole" refers to a position between each sound hole and the sound hole immediately before each sound hole. The sound hole immediately before each sound hole means a sound hole next to each sound hole that is closer to the entrance of the tube 3 than each sound hole. Also, "just after each sound hole" refers to a position between each sound hole and the sound hole immediately beyond each sound hole. The sound hole immediately beyond each sound hole means a sound hole next to each sound hole that is closer to the exit of the tube 3 than each sound hole. In other words, the sensor installed just before each sound hole and the sensor installed just after each sound hole are arranged in the longitudinal direction of the tube 3 with each sound hole between them. Also, the diameter of each of the multiple reflectors is preferably large enough to leave a gap between the inner diameter of the tube 3 so that ultrasonic waves or electromagnetic waves can pass through the entire tube 3.

[0131] B: Second embodiment Hereinafter, a wind instrument mute device, a detection device, and a calculation method for a radiated sound waveform according to the second embodiment will be described with reference to Fig. 13 and Fig. 14. In the following description, for the sake of simplicity, the same reference numerals are used for the same components as in the first embodiment, and the description of their functions may be omitted. In addition, in the following description, for the sake of simplicity, differences between the second embodiment and the first embodiment will be mainly described.

[0132] B1: Configuration of the detection device Hereinafter, the configuration of the detection device according to the second embodiment will be described with reference to Fig. 13. Fig. 13 is a block diagram showing an example of the configuration of the detection device according to the second embodiment. The detection device 20A includes a first actuator 21, a second actuator 22, a third actuator 23, a first sensor unit 31, a second sensor unit 32, a third sensor unit 33, a fourth sensor unit 34, a storage device 80A, and a processing device 90A.

[0133] The storage device 80A is a computer-readable recording medium, similar to the storage device 80. The storage device 80A includes a nonvolatile memory and a volatile memory. The nonvolatile memory is, for example, a ROM, an EPROM, and an EEPROM. The volatile memory is, for example, a RAM.

[0134] The storage device 80A stores a program p2 and various information. The program p2 defines the operation of the detection device 20A. The storage device 80A may store the program p2 read from a storage device in a server (not shown). In this case, the storage device in the server is an example of a computer-readable recording medium. The storage device 80A differs from the storage device 80 in that it stores the program p2 instead of the program p1 and does not have the sound hole opening and closing pattern database 81, but is the same in other respects.

[0135] The processing device 90A includes one or more CPUs. The one or more CPUs are an example of one or more processors. Each of the processing device, processor, and CPU is an example of a computer.

[0136] The processing device 90A reads the program p2 from the storage device 80A. The processing device 90A executes the program p2 to function as a control unit 91, a first signal processing unit 92, a tube shape estimation unit 92c, a second signal processing unit 93, a third signal processing unit 94, a fourth signal processing unit 95, and a physical model sound source unit 96. At least one of the control unit 91, the first signal processing unit 92, the tube shape estimation unit 92c, the second signal processing unit 93, the third signal processing unit 94, the fourth signal processing unit 95, and the physical model sound source unit 96 may be realized by a circuit such as a DSP, an ASIC, a PLD, or an FPGA. The processing device 90A differs from the processing device 90 in that the processing device 90A functions as the tube shape estimation unit 92c instead of the pattern estimation unit 92a and the tube shape model estimation unit 92b, but is the same in other respects.

[0137] The tubular shape estimating unit 92c acquires amplitude information of the sound pressure levels at the sensors 31a to 31h from the first signal processing unit 92. The tubular shape estimating unit 92c estimates the tubular shape based on the amplitude information of the sound pressure levels at the sensors 31a to 31h.

[0138] The estimation model in the tube shape estimation unit 92c is trained by a machine learning method using a regression technique described below.

[0139] Fig. 14 is a cross-sectional view showing a simple physical model according to the second embodiment. As shown in Fig. 1, the tube shape of a clarinet 1 is originally a shape having multiple tone holes whose positions are fixed, but the simple physical model shown in Fig. 14 assumes a tube shape having a single tone hole 5 whose position in the longitudinal direction is variable, and the distance between the single tone hole 5 and the bell outlet portion 3a is variable.

[0140] 14 shows an operator 6 for opening and closing a single sound hole 5. In the simple physical model, a state in which the single sound hole 5 is closed represents a state in which all sound holes are closed. Note that in the simple physical model, a state in which all sound holes are closed may be represented as a state in which there are no sound holes at all.

[0141] For example, in the case of pitch C4, as shown in Figure 5, of the open tone holes in an actual clarinet 1, the closest tone hole to the mouthpiece 2 is the ninth tone hole. To express a shape that can produce the pitch C4 using a simple physical model, it is sufficient to open only one hole at the location of the ninth tone hole and then adjust the position of the bell outlet.

[0142] The positions of the tone holes and the bell outlet that can produce the pitch C4 are given as continuous-value parameters. In the second embodiment, combinations of the tone hole positions, the bell outlet positions, and the corresponding pitch C4 are prepared in advance as output data of a trained model using a neural network. The tone hole positions and the bell outlet positions indicate characteristic shape parameters of the simple physical model. Hereinafter, the tone hole positions and the bell outlet positions are referred to as model shape parameters. Similarly, for other pitches, combinations of model shape parameters and corresponding pitches are prepared in advance as output data of a trained model using a neural network.

[0143] A machine learning device for a neural network model inputs standing wave sound pressure distribution information I1 to In as input data to a neural network model, and trains the neural network model to have a correlation between the standing wave sound pressure distribution information I1 to In as input data and model shape parameters as output data.

[0144] More specifically, the machine learning device inputs the standing wave sound pressure distribution information I1(L1(1), L2(1), . . ., Lm(1)), . . ., and In(L1(n), L2(n), . . ., Lm(n)) constituting the training data to the input layer of the neural network as input data.

[0145] The machine learning device repeatedly adjusts the weights associated with each synapse so as to reduce the value of the evaluation function by using an evaluation function that compares the output data output as an inference result from the output layer of the neural network, i.e., the model shape parameters of the pitch corresponding to the standing wave sound pressure distribution information I1 to In, with the output data constituting the teaching data, i.e., the model shape parameters. Here, adjusting the weights associated with each synapse is called backpropagation.

[0146] When the machine learning device determines that a predetermined training end condition is satisfied, the machine learning device ends the machine learning and stores the neural network model at that point as a trained model in the storage device 80A. The predetermined training end condition is, for example, that the number of iterations of the series of training processes described above reaches a predetermined number, and that the value of the evaluation function becomes smaller than an allowable value.

[0147] C: Modification The present invention is not limited to the above embodiment, and various modified examples can be adopted within the scope of the present invention. Specific modified examples are exemplified below. Two or more aspects arbitrarily selected from the following examples can be appropriately combined within a range that does not contradict each other. In the modified examples exemplified below, the symbols used in the above explanation are used for elements whose actions and functions are equivalent to those of the above embodiment, and detailed explanations of each are appropriately omitted.

[0148] C1: First modified example In the above embodiment, the multiple sensors of the first sensor unit 31 were arranged at intervals from each other in the longitudinal direction of the pipe 3, but the multiple sensors may also or instead be arranged at intervals in the circumferential direction of the pipe 3.

[0149] Ideally, the sound pressure distribution of standing waves occurring inside the tube 3 is detected on the central axis C1 of the tube 3. In a configuration in which multiple sensors are arranged in the circumferential direction, even if the fixed positions of the multiple sensors are shifted for some reason, good detection of standing waves is possible by selectively using a sensor closer to the central axis C1. Furthermore, even if there is an obstacle such as a protrusion inside the tube 3, good detection of standing waves is possible by selectively using a sensor that is less affected by the obstacle.

[0150] C2: Second modified example In the above embodiment, the first actuator 21 is an actuator that generates waves in the audible sound band, which is a frequency band of 20 Hz to 20 kHz, but it may be an actuator that generates ultrasonic waves, which are a frequency band higher than the audible sound band. For example, a piezoelectric element may be used as the actuator that generates ultrasonic waves. In this case, the sensors of the first sensor unit 31 may be piezoelectric elements.

[0151] Ultrasonic waves are more likely to attenuate inside the tube 3 than sound waves. Therefore, the ultrasonic waves attenuate from the position of the first actuator 21 towards the bell outlet 3a, and the component reflected at the bell outlet 3a decreases. Therefore, ultrasonic waves are easily observed as traveling waves inside the tube 3. Ultrasonic waves are also easily attenuated at open sound holes. For this reason, multiple sensors are placed at intervals in the longitudinal direction of the tube 3, and the intensity of the ultrasonic waves is detected by each sensor, thereby measuring the attenuation pattern of the ultrasonic waves.

[0152] Since the ultrasonic attenuation pattern is affected by the open / closed state of each tone hole, the tone hole open / close pattern can be estimated from the ultrasonic attenuation pattern. In this way, by using a plurality of sensors arranged at intervals in the longitudinal direction of the tube 3 inside the tube 3, the ultrasonic attenuation pattern can be measured, thereby further improving the accuracy of estimating the tone hole open / close pattern. Furthermore, according to this modification, since no audible sound is generated, when the detection device 20 of this modification is applied to a wind instrument mute device 10, the player can play the clarinet 1 with the sound generated around the clarinet 1 reduced.

[0153] Each sensor is preferably located as close as possible to each sound hole, and at least one of the sensors is preferably located at bell outlet portion 3a.

[0154] As described above, it is possible to observe the density distribution of ultrasonic standing waves by installing one or more reflectors at the outlet of the pipe 3 or inside the pipe 3. Therefore, the density distribution of ultrasonic standing waves may be detected by the detection device according to this modified example.

[0155] C3: Third modified example In the above embodiment, the first actuator 21 that vibrates the air in the pipe 3 is used as a generator of waves that propagate inside the pipe 3, but an oscillator that generates electromagnetic waves and an antenna may be used. In this case, a plurality of antennas may be used as the plurality of sensors of the first sensor unit 31.

[0156] Like ultrasonic waves, electromagnetic waves are likely to attenuate within the pipe 3. Therefore, electromagnetic waves are likely to be observed as traveling waves within the pipe 3. Furthermore, electromagnetic waves are likely to attenuate at open sound holes. For this reason, a number of sensors are arranged at intervals within the pipe 3 in the longitudinal direction of the pipe 3, and the electromagnetic wave intensity of the electromagnetic waves is detected by each sensor, thereby measuring the attenuation pattern of the electromagnetic waves.

[0157] Since the attenuation pattern of the electromagnetic waves is affected by the open / closed state of each sound hole, the sound hole open / close pattern can be estimated from the attenuation pattern of the electromagnetic waves. In this way, by using a plurality of sensors arranged at intervals in the longitudinal direction of the tube 3 inside the tube 3, the attenuation pattern of the electromagnetic waves can be measured, thereby further improving the accuracy of estimating the sound hole open / close pattern. Furthermore, according to this modified example, since no audible sound is generated, when the detection device 20 of this modified example is applied to a wind instrument mute device 10, the player can play the clarinet 1 with reduced sound generated around the clarinet 1. In this case, the output of the generating unit is set to 100 mW / cm2 in consideration of the effect of electromagnetic waves on the human body. 2 It is preferable to do the following (https: / / acoustics.jp / qanda / answer / 78.html).

[0158] As described above, it is possible to observe the density distribution of the standing wave of the electromagnetic wave by installing one or more reflectors at the outlet of the tube 3 or inside the tube 3. Therefore, the density distribution of the standing wave of the electromagnetic wave may be detected by the detection device according to this modified example.

[0159] C4: Fourth modified example The attenuation of the traveling waves in the audible sound band may be observed, and the sound hole open / close pattern may be estimated based on the traveling wave information. The traveling wave information is information on the distribution of traveling waves. For example, traveling waves in the audible sound band are relatively hard to attenuate, but tend to attenuate easily behind the open sound holes. Therefore, by installing sensors of the first sensor unit 31 just before each sound hole and just after each sound hole, and comparing the outputs of the installed sensors, the open / closed state of each sound hole can be determined.

[0160] For example, the output of the immediately preceding sensor may be compared with the output of the immediately following sensor, and when the output of the immediately following sensor is greater than the output of the immediately preceding sensor and the difference between the output of the immediately following sensor and the output of the immediately preceding sensor is equal to or greater than a certain value, it may be determined that the sound hole to be distinguished is open. The immediately preceding sensor is a sensor provided at a position immediately preceding the sound hole to be distinguished. The immediately following sensor is a sensor provided at a position immediately following the sound hole to be distinguished. The immediately preceding sensor and the immediately following sensor are disposed on either side of the sound hole to be distinguished.

[0161] According to this configuration, the open / closed state of each sound hole is determined by comparing the output of the immediately preceding sensor with the output of the immediately succeeding sensor, so there is no need to estimate the sound hole opening / closing pattern using a machine learning device. This makes it possible to estimate the sound hole opening / closing pattern with a simpler configuration.

[0162] C5: Fifth variant In the above embodiment, the second actuator 22 is used to vibrate the lead 4, and the second sensor unit 32 is used to detect the vibration of the lead 4. The second sensor unit 32 may be a contact type vibration sensor such as a piezoelectric element or an acceleration sensor, or a non-contact type vibration sensor such as a photocoupler, but is not limited thereto, and the displacement of the lead 4 may be detected using a strain sensor. When a strain sensor is used, there is no need to vibrate the lead 4, and the second actuator 22 is not required.

[0163] C6: 6th variant In the first embodiment, a tube shape model is estimated based on the sound hole opening and closing pattern estimated by the pattern estimation unit 92a, and a radiated sound waveform is calculated by the physical model sound source unit 96 based on the estimated tube shape model. In the second embodiment, a radiated sound waveform is calculated by the physical model sound source unit 96 based on the tube shape estimated by the tube shape estimation unit 92c. In contrast, in the fifth modified example, a pitch is determined based on the estimated tube shape model or tube shape, and a recorded waveform corresponding to the pitch may be reproduced as a radiated sound waveform by a PCM (Pulse Code Modulation) sound source unit instead of the physical model sound source unit 96.

[0164] The wind instrument mute device according to this modified example may include both the physical model sound source section 96 and the PCM sound source section. For example, the wind instrument mute device may be configured so that the performer can decide whether to calculate the radiated sound waveform using the physical model sound source section 96 or the PCM sound source section.

[0165] C7: 7th variant In the above embodiment, the clarinet 1 is exemplified as a wind instrument, but the wind instrument may be another reed instrument such as an oboe, a saxophone, a bassoon, etc. In the case of a double reed instrument such as a bassoon, the model relating to the dynamic characteristics of a single reed used in the reed dynamic characteristics block 961 may be changed to a model relating to the dynamic characteristics of a double reed.

[0166] D: Notes From the above-described exemplary embodiments, the following configurations can be understood, for example.

[0167] A detection device according to one aspect (aspect 1) of the present disclosure comprises a generating unit that generates waves that propagate within a tube of a wind instrument, and a first sensor unit having a plurality of sensors that detect the waves, wherein the generating unit and the first sensor unit are disposed within the tube, and each of the plurality of sensors is disposed at intervals from one another in the longitudinal direction of the tube.

[0168] According to this aspect, by having multiple sensors, it is possible to detect the distribution of standing waves occurring within the tube, and to infer the open / closed state of each of the multiple tone holes from the distribution of the standing waves. Since the pitch is detected from the inferred open / closed state of the multiple tone holes, the detection result is less susceptible to the influence of resonance characteristics, such as the strength of resonance of a fingered pitch being weaker than the strength of resonance of other pitches. Therefore, erroneous detection of pitch is suppressed. Furthermore, since each of the multiple sensors is arranged at intervals from each other in the longitudinal direction of the tube, it is possible to more accurately detect standing waves occurring within the tube. Therefore, it is possible to more accurately detect pitch.

[0169] A detection device according to one aspect (aspect 2) of the present disclosure further includes a second actuator that vibrates a reed of the wind instrument, and a second sensor unit having one or more sensors that detect vibration of the reed, the second actuator and the second sensor unit being positioned on the reed.

[0170] According to this aspect, the resonance characteristics of the reed and the static opening of the reed can be detected, so that the playing state of the wind instrument can be detected more accurately.

[0171] A detection device according to one aspect (aspect 3) of the present disclosure further includes a third actuator that vibrates the air in the mouth of a player playing the wind instrument, and a third sensor unit having one or more sensors that detect the vibration of the air in the mouth, the third actuator and the third sensor unit being positioned within the mouthpiece of the wind instrument.

[0172] According to this aspect, the shape of the inside of the mouth of the player can be detected, so that the playing state of the wind instrument can be detected more accurately.

[0173] A detection device according to one embodiment (embodiment 4) of the present disclosure further includes a fourth sensor unit having one or more sensors for detecting the breath pressure of a player playing the wind instrument, the fourth sensor unit being positioned within the mouthpiece of the wind instrument.

[0174] According to this aspect, the breath pressure of the player can be detected, so that the playing state of the wind instrument can be detected more accurately.

[0175] In a detection device according to one aspect (aspect 5) of the present disclosure, the generating unit is a first actuator that generates sound waves by vibrating the air inside a tube of the wind instrument, and each of the multiple sensors detects the sound waves.

[0176] According to this aspect, sound waves propagating in the pipe are detected by a plurality of sensors spaced apart from one another in the longitudinal direction of the pipe. Since sound waves propagating in the pipe appear as standing waves, each sensor can detect a sound pressure level according to the sound pressure distribution of the standing waves in the pipe. The sound pressure distribution of the standing waves can be estimated from the detection results of the sound pressure levels by each sensor.

[0177] A detection device according to one aspect (aspect 6) of the present disclosure comprises a first actuator that generates sound waves by vibrating the air inside a tube of a wind instrument, a first sensor unit having a plurality of sensors that detect the sound waves, and a first mounting unit that positions the first actuator and the first sensor unit inside the tube.

[0178] Sound waves propagating inside a pipe appear as standing waves, and in order to detect the sound pressure distribution of the standing waves, it is preferable to detect the sound waves at a position close to the central axis of the pipe. According to this embodiment, since multiple sensors are disposed inside the pipe, even if the position of the first attachment part is shifted, the sensor close to the central axis of the pipe can be selectively used, and the sound pressure distribution of the standing waves can be detected more accurately.

[0179] In a detection device according to one aspect (aspect 7) of the present disclosure, each of the multiple sensors is disposed at intervals from one another in the longitudinal direction of the pipe.

[0180] According to this aspect, the multiple sensors are arranged at intervals from one another in the longitudinal direction of the pipe, so that the sound pressure distribution of standing waves generated within the pipe can be detected more accurately.

[0181] In a detection device according to one aspect (aspect 8) of the present disclosure, the wind instrument has one or more tone holes, and the multiple sensors are arranged in the longitudinal direction on either side of the tone holes.

[0182] According to this aspect, each of the multiple sensors is disposed immediately before and immediately after the sound hole, and the open / closed state of each sound hole is determined by comparing the output of the immediately before sensor with the output of the immediately after sensor, so there is no need to use a machine learning device to estimate the sound hole open / close pattern. This makes it possible to estimate the sound hole open / close pattern with a simpler configuration.

[0183] A mute device for a wind instrument according to one embodiment (embodiment 9) of the present disclosure comprises the detection device and a blocking device arranged between the mouthpiece and the tube of the wind instrument, blocking air flowing from the mouthpiece into the tube.

[0184] According to this embodiment, the space inside the tube is not connected to the space inside the blocking device that blocks the air from flowing into the tube from the mouthpiece. Therefore, the breath blown into the mouthpiece by the player does not flow into the tube. As a result, the wind instrument is muted.

[0185] A method for calculating a radiated sound waveform according to one embodiment (embodiment 10) of the present disclosure estimates a tube shape model indicating the tube shape of a wind instrument based on standing wave information regarding the distribution of standing waves generated within the tube of the wind instrument, and calculates a waveform related to the radiated sound from the wind instrument based on the estimated tube shape model and breath pressure information related to the breath pressure of the player playing the wind instrument.

[0186] According to this aspect, a tube shape model is determined from the detected standing waves. The tube shape model is a model that estimates pitch information and timbre information from the tube shape according to the fingering of the player of the wind instrument, so a sound waveform that more accurately reproduces the playing state of the wind instrument is calculated. Also, according to this aspect, breath pressure information is generated based on the detected breath pressure of the player, so a sound waveform that matches the playing timing, strength of breath pressure, etc. of the player is calculated based on the breath pressure information.

[0187] In a method for calculating a radiated sound waveform according to one embodiment (embodiment 11) of the present disclosure, estimating the tube shape model includes inputting the standing wave information and outputting a sound hole opening / closing pattern indicating a combination of the open / closed states of each of a plurality of sound holes in the wind instrument, and determining the tube shape model based on the output sound hole opening / closing pattern.

[0188] According to this aspect, a tone hole opening and closing pattern is estimated from the detected standing waves, and a tube shape model is determined based on the estimated tone hole opening and closing pattern. The tube shape model is a model that estimates pitch information and timbre information from the tube shape according to the fingering of the player on the wind instrument, so that a sound waveform that more accurately reproduces the playing state of the wind instrument is calculated.

[0189] In the method for calculating a radiated sound waveform according to one embodiment (embodiment 12) of the present disclosure, the frequency of the standing wave is included in the audible sound band.

[0190] According to this aspect, waves in the audible range, i.e., sound waves, are less likely to attenuate within the tube and tend to appear as standing waves. Therefore, by generating sound waves within the tube and detecting the standing waves with a plurality of sensors, the sound hole opening and closing pattern can be estimated.

[0191] A method for calculating a radiated sound waveform according to one embodiment (embodiment 13) of the present disclosure estimates the tube shape model using a trained model in which the correlation between the standing wave information and a sound hole opening / closing pattern indicating a combination of the open / closed states of each of a plurality of sound holes in the wind instrument has been trained.

[0192] According to this aspect, when the standing wave information is input to the trained model, the sound hole opening and closing pattern corresponding to the standing wave information is output, and the tube shape model is estimated from the sound hole opening and closing pattern output from the trained model. Therefore, since there is no need to develop a complex program for estimating the sound hole opening and closing pattern from the standing wave information, the tube shape model can be easily estimated.

[0193] A method for calculating a radiated sound waveform according to one embodiment (embodiment 14) of the present disclosure estimates a tube shape model indicating the tube shape of a wind instrument based on traveling wave information regarding the distribution of traveling waves generated within the tube of the wind instrument, and calculates a waveform related to the radiated sound from the wind instrument based on the estimated tube shape model and breath pressure information related to the breath pressure of the player playing the wind instrument.

[0194] According to this aspect, a tube shape model is determined from the detected traveling wave. The tube shape model is a model that estimates pitch information and timbre information from the tube shape according to the fingering of the player of the wind instrument, so a sound waveform that more accurately reproduces the playing state of the wind instrument is calculated. Also, according to this aspect, breath pressure information is generated based on the detected breath pressure of the player, so a sound waveform that matches the playing timing, strength of breath pressure, etc. of the player is calculated based on the breath pressure information.

[0195] In a method for calculating a radiated sound waveform according to one embodiment (embodiment 15) of the present disclosure, estimating the tube shape model includes inputting the traveling wave information and outputting a sound hole opening / closing pattern indicating a combination of the open / closed states of each of a plurality of sound holes in the wind instrument, and determining the tube shape model based on the output sound hole opening / closing pattern.

[0196] According to this aspect, a tone hole opening and closing pattern is estimated from the detected traveling wave, and a tube shape model is determined based on the estimated tone hole opening and closing pattern. The tube shape model is a model that estimates pitch information and timbre information from the tube shape according to the fingering of the player on the wind instrument, so that a sound waveform that more accurately reproduces the playing state of the wind instrument is calculated.

[0197] In the method for calculating a radiated sound waveform according to one aspect (aspect 16) of the present disclosure, the frequency of the traveling wave is equal to or higher than the ultrasonic band.

[0198] According to this aspect, waves above the ultrasonic band are likely to attenuate in the pipe and appear as traveling waves. Therefore, by generating ultrasonic waves or electromagnetic waves in the pipe and detecting the traveling waves with multiple sensors, the sound hole opening and closing pattern can be estimated.

[0199] A method for calculating a radiated sound waveform according to one embodiment (embodiment 17) of the present disclosure estimates a change in the shape of the reed based on reed vibration information related to the vibration of the reed of the wind instrument, and calculates a waveform related to the radiated sound based on the estimated tube shape model, the estimated change in the shape of the reed, and the generated breath pressure information.

[0200] According to this aspect, the resonance characteristics and the static opening of the reed are estimated from the detected vibration information, and therefore it is possible to estimate whether the performer is performing a bend technique, and a sound waveform that more accurately reproduces the performance state of the wind instrument is calculated.

[0201] A method for calculating a radiated sound waveform according to one embodiment (embodiment 18) of the present disclosure estimates the shape of the oral cavity of a player playing a wind instrument having a manipulator based on vibration information related to the vibration of air in the oral cavity, and calculates a waveform related to the radiated sound from the wind instrument based on operation information indicating the player's operation of the manipulator, the estimated shape of the oral cavity, and breath pressure information related to the player's breath pressure.

[0202] According to this aspect, the shape of the mouth of the player is estimated based on the detected vibration of the air in the mouth, and therefore the state of the embouchure of the player and whether or not the player is using the flute technique can be estimated, so that a sound waveform that more accurately reproduces the playing state of the wind instrument can be calculated.

[0203] A method for calculating a radiated sound waveform according to one embodiment (embodiment 19) of the present disclosure determines a pitch based on the operation information, the shape of the oral cavity, and the breath pressure information, and calculates a recorded waveform corresponding to the determined pitch as a waveform related to the radiated sound.

[0204] According to this embodiment, the pitch is determined based on the operation information of the wind instrument by the player, the shape of the inside of the mouth of the player, and the breath pressure information of the player. When a PCM sound source is prepared that records waveforms corresponding to each pitch, the radiated sound waveform can also be calculated based on the waveforms corresponding to each pitch recorded in the PCM sound source.

[0205] A method for calculating a radiated sound waveform according to one aspect (aspect 20) of the present disclosure outputs a waveform related to the radiated sound as an electrical signal.

[0206] According to this aspect, a sound waveform that reproduces the performance state of a wind instrument is output as an electrical signal, so that the performer can listen to the reproduced performance using a speaker or headphones.

[0207] According to the above aspect, a mute device for a wind instrument according to one aspect (aspect 21) of the present disclosure comprises a processing device having the detection device, a blocking device provided between the mouthpiece and the tube of the wind instrument and blocking air flowing into the tube from the mouthpiece, a pattern estimation unit that estimates a sound hole opening and closing pattern indicating a combination of the open and closed states of each of a plurality of sound holes in the wind instrument based on the detection results by the first sensor unit, a reed state estimation unit that estimates a change state of the shape of the reed based on the detection results by the second sensor unit, an oral cavity shape estimation unit that estimates the shape of the oral cavity based on the detection results by the third sensor unit, and a breath pressure information generation unit that generates breath pressure information, which is information regarding breath pressure, based on the detection results by the fourth sensor unit, and the processing device estimates a tube shape model based on the sound hole opening and closing pattern estimated by the pattern estimation unit, and calculates a waveform related to the sound radiated from the wind instrument based on the estimated tube shape model, the estimated change state of the reed shape, the estimated shape of the oral cavity, and the generated breath pressure information.

[0208] According to this aspect, the tone hole opening and closing pattern is estimated, and a tube shape model is determined based on the estimated tone hole opening and closing pattern. Also, according to this aspect, the resonance characteristics of the reed, the static opening of the reed, and the shape of the player's mouth are estimated. Also, according to this aspect, a sound waveform is calculated based on the breath pressure information, in accordance with the player's performance timing, the strength of the breath pressure, and the like. Therefore, it is possible to estimate the state of the player's embouchure, and whether or not the player is using a bend technique or a flute technique, and therefore a sound waveform that more accurately reproduces the performance state of the wind instrument is calculated. [Explanation of symbols]

[0209] 1...clarinet, 2...mouthpiece, 3...tube, 4...reed, 5a, 5b, 5c, 5d, 5e...tone holes, 6a, 6b, 6c, 6d, 6e...controllers, 10...mute device for wind instrument, 20, 20A...detection device, 21...first actuator, 22...second actuator, 23...third actuator, 31...first sensor portion, 32...second sensor portion, 33...third sensor portion, 34...fourth sensor portion, 41...first mounting portion, 42...second mounting portion, 43...third mounting portion, 44...fourth mounting portion, 50...shutoff device, OCP...tone hole opening and closing pattern.

Claims

1. A generator for generating waves that propagate through a tube of a wind instrument; a first sensor unit having a plurality of sensors for detecting the waves; Equipped with the generating unit and the first sensor unit are disposed within the pipe, each of the plurality of sensors being spaced apart from one another along the length of the tube; Detection device.

2. a second actuator for vibrating a reed of the wind instrument; a second sensor unit having one or more sensors for detecting vibration of the reed; Further equipped with the second actuator and the second sensor portion are disposed on the lead; The detection device according to claim 1 .

3. A third actuator that vibrates air in a mouth of a player who plays the wind instrument; A third sensor unit having one or more sensors for detecting vibration of air in the oral cavity; Further equipped with the third actuator and the third sensor unit are disposed within a mouthpiece of the wind instrument; The detection device according to claim 1 .

4. a fourth sensor unit having one or more sensors for detecting a breath pressure of a player playing the wind instrument, The fourth sensor unit is disposed in a mouthpiece of the wind instrument. The detection device according to claim 1 .

5. the generating unit is a first actuator that generates sound waves by vibrating air in a tube of the wind instrument, Each of the plurality of sensors detects the acoustic waves. The detection device according to claim 1 .

6. a first actuator that generates sound waves by vibrating air within a tube of a wind instrument; a first sensor unit having a plurality of sensors for detecting the sound waves; a first mounting portion that disposes the first actuator and the first sensor portion within the pipe; Equipped with Detection device.

7. each of the plurality of sensors being spaced apart from one another along the length of the tube; 7. The detection device according to claim 6.

8. The wind instrument has one or more tone holes, The plurality of sensors are arranged in the longitudinal direction with the sound hole therebetween. The detection device according to claim 1 .

9. A detection device according to any one of claims 1 to 8, a blocking device provided between a mouthpiece of the wind instrument and the tube, for blocking air flowing from the mouthpiece into the tube; A mute device for a wind instrument comprising:

10. estimating a tube shape model representing a tube shape of a wind instrument based on standing wave information relating to a distribution of standing waves generated within the tube of the wind instrument; calculating a waveform related to a sound radiated from the wind instrument based on the estimated tube shape model and breath pressure information related to a breath pressure of a player playing the wind instrument; A method for calculating radiated sound waveforms.

11. estimating the tube shape model includes inputting the standing wave information and outputting a tone hole opening / closing pattern indicating a combination of open / closed states of each of a plurality of tone holes in the wind instrument; determining the tube shape model based on the output sound hole opening and closing pattern; The method for calculating a radiated sound waveform according to claim 10.

12. The method for calculating a radiated sound waveform according to claim 10 or 11, wherein the frequency of the standing wave is included in an audible sound band.

13. the tube shape model is estimated using a trained model in which a correlation between the standing wave information and a tone hole opening / closing pattern indicating a combination of opening / closing states of each of a plurality of tone holes in the wind instrument has been trained. The method for calculating a radiated sound waveform according to claim 10.

14. estimating a tube shape model representing a tube shape of the wind instrument based on traveling wave information relating to a distribution of traveling waves generated within the tube of the wind instrument; calculating a waveform related to a sound radiated from the wind instrument based on the estimated tube shape model and breath pressure information related to a breath pressure of a player playing the wind instrument; A method for calculating radiated sound waveforms.

15. estimating the tube shape model includes inputting the traveling wave information and outputting a tone hole opening / closing pattern indicating a combination of open / closed states of each of a plurality of tone holes in the wind instrument; determining the tube shape model based on the output sound hole opening and closing pattern; The method for calculating a radiated sound waveform according to claim 14.

16. The method for calculating a radiated sound waveform according to claim 13 or 14, wherein the frequency of the traveling wave is equal to or higher than an ultrasonic frequency band.

17. estimating a change in shape of the reed based on reed vibration information relating to vibration of the reed of the wind instrument; calculating a waveform related to the radiated sound based on the estimated tubular body shape model, the estimated change in the shape of the reed, and the generated breath pressure information; The method for calculating a radiated sound waveform according to claim 10 or 14.

18. estimating a shape of an interior of a mouth of a player who plays a wind instrument having a manipulator based on vibration information related to vibration of air in the mouth of the player; calculating a waveform related to a sound radiated from the wind instrument based on operation information indicating an operation of the player on the operator, the estimated shape of the oral cavity, and breath pressure information related to the breath pressure of the player; A method for calculating radiated sound waveforms.

19. determining a pitch based on the operation information, the shape of the oral cavity, and the breath pressure information, and calculating a recorded waveform corresponding to the determined pitch as a waveform related to the radiated sound. The method for calculating a radiated sound waveform according to claim 18.

20. A waveform relating to the radiated sound is output as an electrical signal. The method for calculating a radiated sound waveform according to claim 10 or 14.

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