JPH0895580A - Noise controller - Google Patents

Abstract

PURPOSE: To control the tone of a noise by updating a filter coefficient by means of a reference signal and a difference signal. CONSTITUTION: A noise controller comprising a speaker 4 outputting a tone control sound and a first microphone 5 detecting the noise to be tone controlled in the noise whose tone is controlled and forming an error signal is provided with an adapter 6 inputting a reference signal including noise components, forming a tone control signal and outputting it to the speaker 4 and a first target signal forming means 8 for forming a target signal having frequency components for obtaining the target tone of the noise. A first addition means 9 forms the difference signal between the error signal and the target signal. A filter coefficient updating part inputs the reference signal and the difference signal and updates the filter coefficient of the adaptive filter 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a noise control device for canceling noise, and more particularly to a noise control device for controlling the timbre of noise.

[0002]

2. Description of the Related Art Conventionally, there are techniques described in the following fields. FIG. 17 is a diagram showing a conventional noise control device. As shown in the figure, a cancel space 3 is provided in a stage subsequent to the muffler 2 that consumes the acoustic energy of the exhaust gas from the engine 1, which is a power source. A speaker 4 that outputs a cancel sound that cancels noise from the muffler 2 is provided in the cancel space 3. This cancellation sound is equal to the noise level and is in antiphase with the noise phase. The noise from the muffler 2 is reduced in level due to the interference between the noise from the muffler 2 and the speaker 4, and the tail pipe 3-is generated as residual noise.
It is released to the atmosphere from 1. A microphone 5 is provided near the residual noise emitted to the outside air, and the microphone 5 converts the residual noise into an error signal Sm (n).
A power source such as a motor may be used instead of the engine 1, and in this case, the muffler 2 will be an air conditioning duct or the like instead.

An adaptive filter 6 for forming a cancel signal Sc (n) for outputting a cancel sound to the speaker 4 receives a reference signal which is a controlled signal, and a non-cyclic filter FIR (Finite) whose filter coefficient is variable. Impulse R
esponse). The filter coefficient updating unit 7 which receives the error signal and the reference signal from the microphone 5 controls the variable filter coefficient of the adaptive filter 6 so that the error signal is minimized. The adaptive filter 6 and the filter coefficient updating unit 7 are DSPs (Digital Signal Proces).
sor).

FIG. 18 is a diagram showing the structure of the adaptive filter shown in FIG. As shown in the figure, the adaptive filter 6 is provided with a plurality of delay devices for inputting the reference signal q (n) and sequentially delaying the reference signal q (n), each of the delay devices being provided with a multiplier, and the output of the multiplier. Is added to form a cancellation signal. Here, the multiplication coefficients (filter coefficients) of each of the plurality of multipliers are C0, C1, C2, ..., Ck.

The filter coefficient updating unit 7 in FIG. 17 updates the multiplication coefficient as follows. Cp (n + 1) = Cp (n) + α × q (np) × Sm (n) (p = 0,1,2,
, K) where Sm (n) is an error signal from the microphone 5 and α is a convergence coefficient.

FIG. 19 is a diagram showing frequency components of noise before and after noise control. As shown in this figure (a), the frequency component before control is the primary frequency f1 and 2 of this harmonic component.
It is assumed that the frequencies are second and third frequencies f2 and f3. By the noise control device, the frequency spectrum (component) before the noise control shown in this figure (a) becomes the frequency spectrum after the noise control shown in this figure (b).

[0007]

By the way, the sound emitted from the muffler 2 is an exhaust note which is a sound which is appropriately intense and pleasant and does not generate noise, and an exhaust noise which is a sound of noise. However, sports cars require exhaust notes rather than being quiet. However, since the electronic muffler such as the noise control device is intended only for cancellation, there is a problem that not only exhaust noise but also exhaust note is canceled.

Therefore, in view of the above problems, it is an object of the present invention to provide a noise control device capable of forming an exhaust note by controlling the tone color of the sound from the muffler 2.

[0009]

In order to solve the above problems, the present invention provides a noise control device having the following configuration. That is, a noise control device including a speaker for outputting a tone color control tone for tone color controlling noise and a first microphone for detecting tone color controlled tone color controlled noise and forming an error signal includes a frequency component of noise. An adaptive filter which inputs a reference signal to form a tone color control signal and outputs the tone color control signal to the speaker, and a first signal which forms a target signal having a peak value of sound pressure corresponding to the frequency component of the noise as a target value. Target signal forming means is provided. First microphone connected to the first microphone and first target signal forming means
Means for forming a difference signal between the error signal and the target signal. A filter coefficient updating unit that receives the reference signal and the difference signal updates the filter coefficient of the adaptive filter. Further, the second adding means on the input side of the adaptive filter and the filter coefficient updating section adds the reference signal and the target signal from the first target signal forming means.

Further, in place of the first processing means for extracting a target frequency component from the pulsed rotation signal of the power source and the first target signal forming means, the sound pressure peak of the extracted frequency component is obtained. A second target signal forming means for setting a value to a target sound pressure value may be provided, and the target signal may be output to the first and second adding means.

Further, a rotational speed detecting means for detecting the rotational angular speed from the pulsed rotational signal of the power source and an integer angular order or a non-integer order rotational angular speed of the detected rotational angular speed are formed,
Second setting the rotation angular velocity in the first target signal forming means
The processing means may be provided. Further, instead of the first processing means, a second processing means for enhancing or weakening the frequency component of the error signal may be provided.

Further, as an input signal to the second processing means, a first microphone for detecting noise near the power source may be provided instead of the error signal. Also, instead of the first processing means for extracting a target frequency component from the pulsed rotation signal of the power source and the first target signal forming means, the sound pressure peak value of the extracted frequency component is Second target signal forming means for setting a target sound pressure value is provided, the target signal is output to the first and second adding means, and the reference signal is a pulsed rotation signal of a power source. May be

Further, a transfer characteristic simulating means for simulating a transfer characteristic of sound between the speaker and the first microphone, and a tone color control signal from the adaptive filter are passed to allow the timbre control signal to pass from the first microphone. Third addition means for forming a difference signal from the error signal and using it as a reference signal may be provided. The speaker and the first microphone may be provided in the vehicle compartment to control the timbre of noise in the vehicle compartment.

[0014]

According to the noise control device of the present invention, a target signal having a frequency spectrum for obtaining a target noise timbre is formed, a difference signal between the error signal and the target signal is formed, and the reference signal is generated. Also, by updating the filter coefficient with the difference signal, not only the tone color control of the noise but also the tone color of the noise can be adjusted for the exhaust note that is close to the target signal.

Further, by adding the reference signal and the target signal, the target signal is added to the reference signal even if the reference signal does not have a part of the target signal component. It becomes possible to adjust the timbre of noise by approximating it to the exhaust note. Further, the target frequency component is extracted from the pulsed rotation signal of the power source, and the sound pressure peak value of the extracted frequency component is set to the target sound pressure value, so that the non-integer frequency component is By removing the noise and approximating it to the target exhaust note, it is possible to adjust the timbre of the noise.

Further, the rotational angular velocity is detected from the pulse-shaped rotational signal of the power source, an integer angular order or a non-integer order rotational angular speed of the detected rotational angular velocity is formed, and the target signal corresponding to the rotation of the power source is generated. The frequency can be made variable, and the signal of non-integer order can be used as the target signal.
It is possible to adjust the timbre of noise by approximating it to the target exhaust note.

Further, by emphasizing or weakening only a certain band of the error signal to emphasize or weaken the frequency component, the noise is approximated to the target exhaust note based on the error signal. Thus, the tone color of noise can be adjusted. By detecting noise near the power source instead of the error signal, responsiveness is improved when the frequency sweeps quickly such as when the power source is accelerated.

By forming the reference signal as a pulsed rotation signal of the power source, it is not necessary to form the reference signal, and the structure is simplified. Further, the timbre control signal from the adaptive filter is passed through the transfer simulation characteristic to form a difference signal from the error signal to form a feedback which is used as a reference signal, thereby increasing versatility of use.

By providing the speaker and the first microphone inside the vehicle compartment and controlling the tone color of the noise inside the vehicle compartment, not only the noise from the exhaust pipe but also the tone color of the noise inside the vehicle compartment can be controlled. .

[0020]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a noise control device according to a first embodiment of the present invention. In this figure, the configuration different from the conventional configuration of FIG. 17 is a target signal forming means for forming a target signal so that the tone color of the noise from the muffler 2 can be adjusted in order to obtain an exhaust note that gives a smooth rotation feeling of the engine 1. 8 and the target signal T from the target signal forming means 8.
Error signal S from microphone 5 by inverting (n)
and the addition means 9 for outputting the signal E (n) added to m (n) to the filter coefficient updating unit 7.

FIG. 2 is a diagram showing the configuration of the target signal forming means 8 of FIG. As shown in this figure, the target signal forming means 8
Is an angular velocity storage unit 8 for storing angular velocity ω1, ω2, ω3 data for the primary, secondary, and tertiary frequency spectra f1, f2, f3 (f1 <f2 <f3) included in the reference signal.
1, 82 and 83 are provided. Each of the angular velocity storage units 81 and 8
The sine wave forming units 84, 85, 86 connected to the Nos. 2, 83 form sine waves at their respective angular velocities. Multipliers 87, 88, 8 connected to the sine wave forming units 84, 85, 86, respectively.
9 is the gain g1, g2, g for the sine wave input to each
3 (g1>g2> g3) is multiplied. The multipliers 87, 8
An adding means 90 connected to 8, 89 adds these outputs to form a target signal and outputs it to the adding means 9. Therefore, the following relational expression holds as E (n) =-T (n) + Sm (n). Since the adaptive filter 6 operates so that E (n) = 0 and controls the timbre of noise, E (n) = − T (n) + Sm (n) = 0, that is, Sm (n) = T (n). Therefore, the target signal forming means 8 allows the tone color control noise at the position of the microphone 5 to approximate the target signal, and enables adjustment of the tone color of the tone color control noise.

FIG. 3 is a diagram showing frequency characteristics of an exhaust note whose tone color is controlled by the first embodiment. As shown in this figure (a), the frequency spectrum of the noise before control is irregular in the peak values p1, p2, p3 of the sound pressure for the primary, secondary, and tertiary frequencies f1, f2, f3. , That is, p3>p1> p2. As shown in this figure (b), the output of the target signal forming means 8 is adjusted by adjusting the gains g1, g2 and g3 of the multipliers 87, 88 and 89 so that the peak value of the sound pressure with respect to the frequency becomes regular. , That is, change to p1>p2> p3. That is, it is aimed to form an exhaust note in which the peak value of the sound pressure decreases as the frequency increases. As shown in this figure (c), the frequency spectrum of the tone-color-controlled noise after control becomes an exhaust note, and the exhaust noise before control is converted into an exhaust note.

Therefore, according to this embodiment, not only the noise can be canceled by the noise control, but also the tone color of the noise can be adjusted to the exhaust note which is close to the target signal. By the way, when there is no part of the target signal component of the target signal forming means 8 in the reference signal, there is a problem that some of the target signal component corresponding to the output of the adaptive filter 6 is not output. explain.

FIG. 4 is a diagram showing a noise control device according to a second embodiment of the present invention. In the figure, the different configuration is to add the target signal forming means 8 to the reference signal, so that the adding means 10 is provided on the input side of the adaptive filter 6 and the filter coefficient updating unit 7.
Is to be provided. FIG. 5 is a diagram showing frequency characteristics of an exhaust note whose tone color is controlled by the second embodiment. This figure (a) shows the frequency spectrum in which the sound pressure peaks exist at the frequencies f1 and f2 before control, and the figure (b) shows the frequency spectrum of the target signal from the target signal forming means 8, which is frequencies f1 and f2. , F3 has a sound pressure peak, and this figure (c) shows the frequency spectrum of the tone color control noise after control. However, this figure (d) is the spectrum of the to-be-controlled color control noise after control in the case where the target signal is not added to the reference signal. Compared with this figure (c), the frequency f3
There is no sound pressure peak corresponding to. Therefore, according to the present embodiment, even if the reference signal does not have a part of the target signal spectrum, by adding the target signal to the reference signal, the noise is approximated to the target exhaust note,
The tone of noise can be adjusted.

By the way, in the tail pipe 3-1 which is the outlet of the noise, in addition to the integer harmonics caused by the engine speed, the non-integer frequency spectrum generated due to the structure of the muffler 2 is generated. , This is exhaust noise, so there is a problem that it should be removed. The improvement for this problem will be described below. FIG. 6 is a diagram showing a noise control device according to a third embodiment of the present invention. In this figure, FIG.
The second embodiment differs from the second embodiment in that processing means 11 for inputting a pulsed rotation signal from the engine 1 is provided, and the processing means 11 is a band-pass filter for passing signals of frequencies f1, f2 and f3 of integer orders. (BPF). In this case, the configuration of the target signal forming means 8'is configured by removing the angular velocity storage sections 81, 82, 83 and the sine wave forming sections 84, 85, 86, and comprising multipliers 87, 88, 89 and an adding means 90, The multipliers 87, 88, 89 are the frequency f of the processing means 11.
They are connected to band pass filters that pass 1, f2 and f3, respectively.

FIG. 7 is a diagram showing the frequency characteristics of an exhaust note whose tone color is controlled by the third embodiment. As shown in FIG. 4A, it is assumed that the frequency spectrum of noise before control includes a non-integer order spectrum in addition to an integer order spectrum. As shown in FIG. 7B, the target signal forming means 8'forms an integer-order target signal by the rotation signal of the engine 1. As shown in FIG. 7C, the non-integer-order spectrum is removed from the frequency spectrum of the tone-color-controlled noise after control.

Therefore, according to this embodiment, it is possible to adjust the tone color of noise by removing the non-integer-order spectrum and approximating the tone color control noise to the target exhaust note. By the way, when the rotation speed of the engine 1 changes, there is a problem that the frequency of the target signal forming means 8 should be controlled corresponding to this change, and an improvement therefor will be described below.

FIG. 8 is a diagram showing a noise control device according to a fourth embodiment of the present invention. As shown in this figure, the second part of FIG.
The configuration different from that of the embodiment is provided with a rotational angular velocity detecting means 12 for inputting a rotational signal from the engine 1, and the rotational angular velocity detecting means 12 obtains the rotational angular velocity ω of the engine 1. The processing means 13 is provided after the rotational angular velocity detection means 12.
The processing means 13 sets the rotational angular velocity of the engine 1 to the angular velocity ω1 = ω with respect to the primary frequency f1.
Angular velocity ω2 = 2 of frequencies f2 and f3 of this harmonic component
With ω, ω3 = 3ω, these are stored in the angular velocity storage units 81, 82, 83 of the target signal forming means 8, respectively. In this way, the frequency of the target signal can be controlled according to the rotation speed of the engine 1. Further, the frequency of the target signal is set to a non-integer frequency according to the rotation speed of the engine 1,
That is, the angular velocity of the primary frequency is multiplied by a non-integer to calculate the angular velocity of the non-integer order, which can be used as follows.

FIG. 9 is a diagram showing frequency characteristics of an exhaust note whose tone color is controlled by the fourth embodiment. This figure (a) shows the frequency spectrum before control, this figure (b) shows the frequency spectrum of the rotation signal of the engine 1, and this figure (c) shows the frequency spectrum of the target signal of the target signal forming means 8. This figure (d) shows the frequency spectrum of the tone-color-controlled noise after control. According to the present embodiment, the frequency of the target signal can be made variable in accordance with the rotation of the engine 1, and a non-integer-order signal can also be used as the target signal, and the toned color control noise is targeted. It becomes possible to adjust the tone color of noise by approximating it to an exhaust note.

FIG. 10 is a diagram showing a noise control device according to a fifth embodiment of the present invention. As shown in this figure, the configuration different from that of the third embodiment of FIG. 6 is that a processing means 14 for inputting an error signal obtained by converting the tone-color control noise by the microphone 5 is provided. Is
For example, it is composed of a band elimination filter. FIG. 11 is a diagram showing frequency characteristics of an exhaust note whose tone color is controlled by the fifth embodiment. The figure (a) shows the frequency spectrum before control, the figure (b) shows the frequency spectrum of the target signal processed by the processing means 14, and the figure (c).
Shows the frequency spectrum of the tone color control noise after control.
As shown in FIGS. 3B and 3C, the secondary frequency is weakened. Thus, according to the present embodiment, based on the error signal corresponding to the tone color control noise, it is possible to emphasize or weaken only a certain band, the tone color control noise to the target exhaust note, It becomes possible to adjust the timbre of noise by approximating it.

FIG. 12 is a diagram showing a noise control system according to the sixth embodiment of the present invention. As shown in this figure, a configuration different from that of the fifth embodiment in FIG. 10 is that a microphone 15 in which an input signal of the processing means 14 is attached in the middle of the exhaust pipe 1-1 of the engine 1 is provided. The signal from the microphone 15 is processed by the processing means 14,
It is used to form the target signal, and it can emphasize or weaken only a certain band to reduce noise to the target exhaust
It becomes possible to adjust the tone color of the to-be-controlled color control noise by approximating it to a note. Since this embodiment can be obtained earlier in time than the fifth embodiment, the response is improved when the frequency is swept quickly such as when the engine 1 is accelerated.

FIG. 13 is a diagram showing a noise control system according to the seventh embodiment of the present invention. As shown in this figure, a configuration different from that of the third embodiment of FIG. 6 is that a pulsed rotation signal of the engine 1 is used as a reference signal. The reference signal may be anything that approximates a noise signal,
By using the rotation signal of the engine 1, it is not necessary to form a reference signal, and the configuration is simplified.

FIG. 14 is a diagram showing a noise control device according to the eighth embodiment of the present invention. As shown in the figure, the configuration different from the third embodiment of FIG. 6 is provided with a transfer characteristic simulating means 16 simulating the transfer characteristic Hd1 of the sound from the speaker 4 to the microphone 5 at the output stage of the adaptive filter 6. The
A tone color control signal passes through the transfer characteristic simulating means 16 and is influenced by the transfer characteristic Hd1 to provide an adder means 17 for forming an error signal and a difference signal. The adder means 17 outputs the noise reproduction signal RNoise. It is to be used as a reference signal for feedback. According to the present embodiment, the formation of the reference signal is unnecessary and the structure is simplified.

FIG. 15 shows a ninth embodiment of the present invention,
It is a figure which shows the noise control apparatus concerning what is used for the tone color control of the noise in a vehicle interior. The noise control device shown in this figure is the one according to the seventh embodiment of FIG. 13 in which the speaker 4 and the microphone 5 are provided in the vehicle interior and used for tone color control in the vehicle interior. In this way, it can be used not only for the tone color control of the exhaust noise but also for the tone color control of the vehicle interior.

FIG. 16 is a diagram showing a noise control system according to a tenth embodiment of the present invention, which is used for tone color control of noise in a vehicle compartment. The noise control device shown in this drawing is the one according to the eighth embodiment of FIG. 14 in which the speaker 4 and the microphone 5 are provided in the vehicle interior and used for tone color control in the vehicle interior. In the same manner as described above, it can be used not only for the tone color control of the exhaust noise but also for the tone color control of the vehicle interior.
Although the use of the seventh and eighth embodiments has been described, it is obvious that the other embodiments can also be used.

In the fifth embodiment of FIG. 10, the reproduction signal RNoise of the eighth embodiment of FIG. 14 may be used instead of the error signal which is the input signal of the processing means 14.

[0037]

As described above, according to the present invention, a target signal having a frequency component for obtaining a target noise tone color is formed, and a difference signal between the error signal and the target signal is formed. Since the filter coefficient is updated by the reference signal and the difference signal, it is possible not only to cancel the noise but also to adjust the tone color of the noise to the exhaust note that is close to the target signal. Furthermore, by adding the reference signal and the target signal, it is possible to adjust the timbre even if the reference signal has no target signal component. It becomes possible to adjust the timbre by removing the frequency component of non-integer order, the frequency of the target signal can be changed according to the rotation of the power source, and the signal of non-integer order can also be used as the target signal. The components can be emphasized or weakened, the response is improved when the frequency is swept quickly such as when accelerating the power source, the configuration can be simplified, feedback can be configured, and not only the noise from the exhaust pipe, It is possible to control the timbre of noise in the passenger compartment.

[Brief description of drawings]

FIG. 1 is a diagram showing a noise control device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a target signal forming means 8 of FIG.

FIG. 3 is a diagram showing frequency characteristics of an exhaust note whose tone color is controlled by the first embodiment.

FIG. 4 is a diagram showing a noise control device according to a second embodiment of the present invention.

FIG. 5 is a diagram showing frequency characteristics of an exhaust note whose tone color is controlled by the second embodiment.

FIG. 6 is a diagram showing a noise control device according to a third embodiment of the present invention.

FIG. 7 is a diagram showing frequency characteristics of an exhaust note whose tone color is controlled by the third embodiment.

FIG. 8 is a diagram showing a noise control device according to a fourth embodiment of the present invention.

FIG. 9 is a diagram showing frequency characteristics of an exhaust note whose tone color is controlled by the fourth embodiment.

FIG. 10 is a diagram showing a noise control device according to a fifth embodiment of the present invention.

FIG. 11 is a diagram showing frequency characteristics of an exhaust note whose tone color is controlled by the fifth embodiment.

FIG. 12 is a diagram showing a noise control device according to a sixth embodiment of the present invention.

FIG. 13 is a diagram showing a noise control device according to a seventh embodiment of the present invention.

FIG. 14 is a diagram showing a noise control device according to an eighth embodiment of the present invention.

FIG. 15 is a diagram showing a noise control device according to a ninth embodiment of the present invention, which is used for tone color control of noise in a vehicle compartment.

FIG. 16 is a diagram showing a noise control device according to a tenth embodiment of the present invention, which is used for tone color control of noise in a vehicle compartment.

FIG. 17 is a diagram showing a conventional noise control device.

18 is a diagram showing a configuration of the adaptive filter 6 of FIG.

FIG. 19 is a diagram showing frequency spectra of noise before and after noise control.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Engine, motor, power source 2 ... Muffler 3 ... Cancellation space 3-1 ... Tail pipe 4 ... Speaker 5, 15 ... Microphone 6 ... Adaptive filter 7 ... Filter coefficient update part 8, 8 '... Target signal forming means 9 10, 17 ... Addition means 11, 13, 14 ... Processing means 12 ... Rotational angular velocity detection means 16 ... Transfer simulation characteristics

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Internal reference number FI Technical display location F16L 55/04 G10K 11/16 H03H 21/00 8842-5J (72) Inventor Toshiaki Kusano Kobe, Hyogo Prefecture 1-22 Gosho-dori, Hyogo-ku, Yokohama

Claims (9)

[Claims] 1. A noise control having a speaker (4) for outputting a tone color control tone for controlling a tone color of noise and a first microphone (5) for detecting an tone color controlled tone-controlled noise and forming an error signal. In the apparatus, an adaptive filter (6) for inputting a reference signal containing a frequency component of noise and forming a tone color control signal and outputting the control signal to the speaker (4), and a target having a target value of the frequency component of the noise First target signal forming means (8) for forming a signal, and first for forming a difference signal between the error signal and the target signal
And a filter coefficient updating unit (7) for updating the filter coefficient of the adaptive filter (6) by inputting the reference signal and the difference signal. . 2. A noise control having a speaker (4) for outputting a tone color control tone for controlling a tone color of noise, and a first microphone (5) for detecting an tone color controlled tone-controlled noise and forming an error signal. In the apparatus, an adaptive filter (6) for inputting a reference signal containing a frequency component of noise and forming a tone color control signal and outputting the control signal to the speaker (4), and a target having a target value of the frequency component of the noise First target signal forming means (8) for forming a signal, and first for forming a difference signal between the error signal and the target signal
Adder means (9), a filter coefficient updating section (7) for updating the filter coefficient of the adaptive filter (6) by inputting the reference signal and the difference signal, the adaptive filter (6) and the The input side of the filter coefficient updating unit (7) is provided with a second adding means (10) for adding the reference signal and the target signal from the first target signal forming means (8). Noise control device. 3. A first processing means (11) for extracting a target frequency component of noise from a pulsed rotation signal of a power source (1) and the first target signal forming means (8) instead of the first processing means (8). And a second target signal forming means (8 ′) for setting a sound pressure peak of the frequency component of the extracted noise to a target sound pressure value, and adding the target signal to the first and second additions. A noise control device according to claim 1 or 2, characterized in that it outputs to means (9, 10). 4. A rotation speed detecting means (1) for detecting a rotation angular speed from a pulsed rotation signal of the power source (1).
2), and second processing means (13) for forming an integer-order or non-integer-order rotation angular velocity of the detected rotation angular velocity and setting the rotation angular velocity in the first target signal forming means (8). The noise control device according to claim 1 or 2, further comprising: 5. The third processing means (14) for emphasizing or weakening the frequency component of an error signal is provided in place of the first processing means (11), according to claim 3. The described noise control device. 6. A second microphone (15) for detecting noise near the power source (1) is provided as an input signal to the second processing means (14) instead of an error signal. The noise control device according to claim 5. 7. A first processing means (1) for extracting a target frequency component from a pulsed rotation signal of a power source (1).
1), instead of the first target signal forming means (8), a second target signal forming means (8 ') for setting the sound pressure of the extracted component to a target sound pressure peak value. The provision target signal is output to the first and second adding means (9, 10), and the reference signal is used as a pulsed rotation signal of the power source (1). The noise control device described in. 8. A transfer characteristic simulating means (16) simulating a transfer characteristic of sound between the speaker (4) and the first microphone (5), and tone color control from the adaptive filter (6). A third adding means (17) is provided, which allows the signal to pass through the transfer characteristic simulating means (16) and forms a difference signal with the error signal from the microphone (5) to be a reference signal. The noise control device according to claim 1, 2, or 5. 9. The speaker according to claim 1, wherein the speaker (4) and the first microphone (5) are provided in a vehicle compartment to control the timbre of noise in the vehicle compartment. The noise control device described in.