JP3287747B2 - Noise sensitive automatic volume control - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a noise-sensitive automatic volume control device mounted on an automobile and automatically adjusting the volume of a sound source signal reproduced and reproduced in the vehicle compartment in accordance with the amount of noise in the vehicle compartment. About.

[0002]

2. Description of the Related Art Conventionally, an audio device is mounted on a vehicle so that sound such as music can be reproduced in a vehicle. Noise such as road noise, wind noise, or engine noise that accompanies the running of the vehicle enters the cabin, and when the noise level increases, sound reproduction in the cabin cannot be performed in a good listening state. Would. Noise is heard differently before and after the passenger compartment. Focusing on this point, a prior art that detects the amount of noise and changes the volume distribution of speakers provided on the front and rear sides of the vehicle compartment according to the noise level is disclosed in, for example, JP-A-4-108207. I have. This prior art is disclosed in Japanese Patent Application Laid-Open No. 58-175400, for example, in which a plurality of speakers are installed in a vehicle compartment and the volume reproduced from the speakers is controlled in accordance with the arrangement of occupants in the vehicle compartment. Is based on

[0003] Further, the prior art for actively reducing the noise in a vehicle cabin by reproducing an acoustic signal that cancels the noise is disclosed in Japanese Patent Application Laid-Open No. H10-157,086.
For example, it is disclosed in JP-A-3-203492. Also, in conjunction with the navigation device mounted on the vehicle,
Prior art techniques for reducing the sound output in a vehicle cabin while traveling in a specific place include, for example, Japanese Patent Application Laid-Open Nos.
305847. More generally,
For example, Japanese Patent Application Laid-Open No. 1-189215 discloses a prior art in which sound output is controlled in accordance with the amount of ambient noise so that the sound output does not become a noise source when nighttime noise is small. This prior art discloses a concept in which an input system for noise detection has a specific frequency characteristic that excludes an acoustic output generated by the input system.

[0004]

Problems to be Solved by the Invention
The seventh prior art aims at eliminating the sense of incongruity by noise-sensitive control due to a difference in the listening position in the passenger compartment. However, there is no disclosure of a specific configuration for control switching, and in particular, there is no idea of performing switching under a long time constant. If the noise responsive control is performed frequently, the reproduction level of the sound source signal being listened to frequently changes, which causes a sense of incongruity. JP-A-5-2155
According to the prior art disclosed in Japanese Patent Application Laid-Open No. H05-305847 and Japanese Patent Application Laid-Open No. 5-305847, it is possible to reduce the sound output in the cabin when the vehicle is traveling or present in a specific place, but to control the volume so that it is easy to hear in response to noise. I can't.

An object of the present invention is to provide a noise-sensitive automatic volume control device capable of appropriately performing automatic volume control based on noise sensitivity based on digital signal processing.

[0006]

SUMMARY OF THE INVENTION The present invention relates to a noise-sensitive automatic volume control device for automatically adjusting the volume of sound reproduced in a vehicle compartment according to the amount of noise in the vehicle compartment so as to make it easy to hear. Volume operation means for performing an operation for adjusting the reproduction volume of a sound source signal to be sound-reproduced, a sound source signal to be sound-reproduced is input as a digital signal, and the sound source signal is subjected to arithmetic processing based on a vehicle interior transfer function and In response to an operation on the sound volume operation means, a gain is controlled in accordance with a reproduction sound volume, a sound source signal processing means for deriving a reference signal for noise level detection, and a sound signal in a vehicle interior, and a digital signal A vehicle interior sound input means for converting and inputting the sound signal, a vehicle signal processing means for digitally processing an acoustic signal input by the vehicle interior sound input means, and deriving a comparison signal for noise level detection, Volume control means for responding to outputs from the source signal processing means and the vehicle interior signal processing means, detecting a noise amount as a difference between a comparison signal with respect to a reference signal, and controlling a sound volume for sound reproduction. It is a noise-sensitive automatic volume control device. The sound signal input to the vehicle interior sound input means is affected by a vehicle interior transfer function on a sound source signal reproduced in the vehicle interior. Even if a sound signal to which the influence of the vehicle interior transfer function is added is subjected to digital signal processing and used as a comparison signal for noise detection, the difference between the comparison signal and the reference signal cannot be reduced to zero in the absence of noise. . For example, when the comparison signal is detected to be larger than the reference signal, control is performed to reduce the volume of the sound reproduced in the vehicle cabin. Although the level of the comparison signal is reduced, the level of the reference signal is further reduced. It will drop and the volume limit will be repeated indefinitely. When the level of the reference signal is higher than the level of the comparison signal, even if noise is applied, the amount of noise is not detected unless the level of the comparison signal is higher than the level of the reference signal, and the volume of the noise is not limited. Since the sound source signal processing means performs an arithmetic process for multiplying the transfer function in the vehicle compartment, the level of the comparison signal and the reference signal in the absence of noise can be matched to make the difference zero. In addition, the reproduction volume for listening to the sound source signal reproduced in the vehicle cabin can be adjusted by operating the volume operation means from the user side. In response to the operation on the volume operation means, the gain of the sound source signal processing means is controlled in accordance with the reproduction volume. Thereby, even if the operation is performed on the volume operation means, the level difference between the reference signal and the comparison signal becomes
In a state without noise, control can be performed so as to be always 0, and it is possible to prevent a situation in which the volume control is repeated indefinitely based on an operation on the volume operation means.

Further, in the present invention, the vehicle compartment signal processing means and the sound source signal processing means limit a frequency band of the detected sound signal and the sound source signal in the vehicle compartment. According to the present invention, the vehicle interior signal processing means and the sound source signal processing means limit the frequency band of the acoustic signal detected in the vehicle interior and the sound source signal. Correspondence with the amount to be detected can be taken. In a very low frequency band, the noise in the passenger compartment is almost constant and has a relatively high sound pressure level regardless of the traveling speed. On the other hand, an acoustic signal in a frequency band that is easily perceived as noise has a low sound pressure level when the vehicle is stopped or running at a low speed. By limiting the frequency band of the acoustic signal in the vehicle compartment detected by the vehicle interior acoustic input means, it is possible to detect an appropriate amount of noise.

[0008]

Further, in the present invention, the sound source signal processing means and the vehicle interior signal processing means perform integration processing on the reference signal and the comparison signal to derive the respective signals. According to the present invention, since the sound source signal processing means and the vehicle interior signal processing means for deriving the reference signal and the comparison signal for detecting the noise amount respectively perform the integration operation processing by the digital signal processing, it is realized by the analog signal processing. It is possible to easily perform an integral operation corresponding to an impossible long time constant. For example, in an analog integrating circuit, if the time constant is set to several seconds, a large-capacity capacitor is prepared and the output level is reduced, so that the practicality is lost. Digital signal processing enables long-term integration, for example, a few seconds, to set the time constant, so that the control waveform of the volume control is smoothed for instantaneous noise changes, and the volume does not cause discomfort in the sense of hearing. Control can be performed.

Further, in the present invention, the time constant in the integration operation processing can be adjusted by an input operation. According to the present invention, since the time constant of the integration operation process can be adjusted by operation, the state of volume control can be adjusted according to the preference of a user who listens to sound reproduction in the vehicle cabin. If the time constant is long, loose control is performed, and if the time constant is short, sharp control is performed.

[0011]

Further, in the present invention, the sound volume control means controls the sound volume for sound reproduction when the detected noise amount exceeds a preset threshold value. According to the present invention, the volume control for sound reproduction is performed when the noise amount exceeds a preset threshold value, and the control is not performed when the noise amount does not exceed the threshold value. , The number of program steps for digital signal processing can be reduced.

Further, in the present invention, the volume control based on the threshold value is performed with a predetermined time constant. According to the present invention, the control of the volume based on the threshold is performed with a predetermined time constant. Even if the noise level exceeds the threshold value, the volume does not change suddenly, and the control is performed slowly according to the time constant. It does not cause such discomfort in hearing.

The present invention further comprises road information detecting means for detecting road information on which the vehicle is traveling, wherein the sound volume control means controls the sound volume for sound reproduction according to the detected road information. Features. According to the present invention,
Road information on which the vehicle is traveling is detected by the road information detecting means. Since the sound volume control means controls the sound volume for sound reproduction in accordance with the detected road information, appropriate sound volume control can be performed according to road information such as a tunnel, an expressway, or traffic congestion.

Also, the present invention responds to a noise amount calculated by a difference between a reference signal of the sound volume control means or the sound source signal processing means and a comparison signal of the vehicle interior signal processing means, and maximizes a sound source signal reproduced by sound. A compressor is provided which controls the level difference between the signal level and the minimum signal level so as to be compressed in conjunction with the noise amount. According to the present invention, when the noise amount calculated by the volume control means is large and the volume of the sound source signal to be reproduced is increased, the level difference between the maximum signal level and the minimum signal level of the sound source signal by the compressor means is increased. Compress. In general, a sound reproducing device has an upper limit on a reproducible sound output, and even if an input signal becomes larger than a certain value, the sound output is saturated, the distortion is increased, and the sound quality is deteriorated. When the sound pressure level to be reproduced is increased by the sound volume control corresponding to the noise amount by the sound volume control means, there is a possibility that the level of the sound source signal is saturated in a high range. Since the level difference between the maximum signal level and the minimum signal level is compressed by the compressor means in conjunction with the noise amount, it is possible to prevent sound quality deterioration due to saturation of the sound source signal. Also, when the input level of the sound source signal is low, the output level is set higher than the input level, so that masking of the sound source signal due to noise can be avoided and sound reproduction can be performed without impairing the dynamic range of the sound source signal. it can.

The present invention further comprises a test signal generating means, wherein the sound source signal processing means and the vehicle interior signal processing means comprise:
The gain is adjusted so that the frequency characteristics and the output levels of the reference signal and the comparison signal respectively derived based on the output from the test signal generating means become equal. According to the present invention, the gain is adjusted based on the signal generated from the test signal generating means so that the outputs of the reference signal and the comparison signal respectively derived from the sound source signal processing means and the passenger compartment signal processing means become equal. By doing so, the volume control can be appropriately performed regardless of the type of the vehicle. Also, acoustic characteristics such as frequency characteristics can be automatically adjusted.

Further, in the present invention, the control amount of the sound volume by the sound volume control means can be adjusted by an operation input. According to the present invention, since the control amount of the sound volume by the sound volume control means can be adjusted by an operation input, the correction amount can be adjusted according to the preference of the user who reproduces and listens to the sound source signal in the passenger compartment. .

Further, the present invention is characterized in that it includes an ON / OFF switching means for switching ON or OFF the control for automatically adjusting the sound volume reproduced in the vehicle compartment. According to the present invention, the control for automatically adjusting the volume of sound reproduced in the vehicle compartment according to the amount of noise can be switched ON or OFF, so that the control can be switched according to the need of the user.

Further, the present invention includes a volume control means for performing an operation for adjusting a reproduction volume of a sound source signal reproduced in a vehicle cabin, wherein the volume control means and the ON / OFF switching means are switched to ON. The control is performed based on the sound volume corresponding to the operation position of the sound volume operation means at the time. According to the present invention, the volume control corresponding to the noise amount is O
Volume control is performed based on the volume corresponding to the operation position of the volume operation means at the time of switching to N. Sound reproduction can be continued while ensuring a sound volume according to the preference of the user who listens to the signal reproduced in the vehicle cabin.

The present invention further comprises a volume control means for performing an operation for adjusting a reproduction volume of a sound source signal reproduced in a vehicle cabin, wherein the volume control means switches the ON / OFF switching means to ON. The control is performed by adding a control amount based on a noise signal to a sound volume based on an operation position of the sound volume operation means when the sound is operated. According to the present invention, the operation position of the volume operation means is adjusted so that the volume corresponding to the noise amount increases based on the ON state of the volume control corresponding to the noise amount, so that a new volume operation means is used. Automatic adjustment of the volume corresponding to the noise amount can be performed without the need.

Further, the present invention comprises a sound volume operation means for performing an operation for adjusting a reproduction volume of a sound source signal reproduced sound in the vehicle interior, and performs a predetermined operation on the sound volume operation means so that the sound is reproduced in the vehicle interior. It is characterized in that the control for automatically adjusting the reproduced volume can be switched on or off. According to the present invention, control for automatic adjustment of the volume is performed by performing a predetermined operation on the volume operation means for performing an operation for adjusting the reproduction volume of the sound source signal reproduced in the vehicle cabin. It can be switched on or off. Thus, there is no need to provide control operation means for switching the control for automatic adjustment of the volume ON or OFF, and the volume operation means can be shared.

The present invention is characterized in that the control is switched to ON when the volume operation means is not operated for a predetermined time or more.
According to the present invention, when the operation on the volume operation means is not performed for a predetermined time or more, the control for automatically adjusting the volume is switched to ON. Once the user's preferred volume for reproducing the sound signal in the vehicle cabin is set, only by not operating the volume operation means, even if the noise becomes loud,
Sound reproduction that is easy to hear can be continued.

Further, the present invention is characterized in that when the volume operation means is operated to a lower volume side than a predetermined operation state, the control is switched to OFF. According to the present invention, when the sound volume operation means is operated to the low sound volume side, the control of the sound volume corresponding to the noise amount is switched to OFF. As a result, a situation in which a loud sound source signal is suddenly input and the volume of the sound reproduced in the vehicle interior is low and the volume is increased is performed, thereby preventing a situation where the sound is reproduced at a very high volume. be able to.

Further, the present invention is characterized in that the operation of the vehicle interior sound input means is stopped when the control for automatically adjusting the volume is switched to OFF. According to the present invention, since the operation of the vehicle interior sound input means is stopped,
Apparently, no noise is detected, and the state substantially shifts to the state before control. Because there is no sudden change in volume,
Switching without discomfort can be performed.

Further, the present invention provides a method for controlling the volume of the noise with respect to the amount of noise by the volume control means before the start of the control when the control for automatically adjusting the volume is turned off. It is characterized in that any of the given control amounts is set to 0, all the thresholds are set to a very high level, and the level coefficient before integration is set to -∞. According to the present invention, in order to set the volume to a state before the start of control, all control amounts provided for each threshold are set to 0, and all thresholds are at a very high level, that is, a level at which noise does not theoretically increase. Or setting the level coefficient before integration to -∞. As a result, since the state is returned to the state before the start of the volume control for the noise amount in the OFF state, the switching can be performed quickly.

Further, the present invention is characterized in that there is provided a sound volume processing means for adjusting a sound volume of a sound source signal reproduced and reproduced by digital signal processing in response to a noise amount from the sound volume control means. According to the present invention, the volume processing unit adjusts the volume of the sound source signal reproduced and reproduced by the digital signal processing in response to the amount of noise from the volume control unit. This is unnecessary, and the electrical configuration can be simplified.

Further, the present invention is characterized in that there is provided independent volume adjusting means for adjusting the volume of the sound source signal reproduced by digital signal processing in response to the amount of noise from the volume controlling means. According to the present invention, since the volume control is performed by the independent volume control means, the configuration of software for digital signal processing by the volume control means can be simplified.

Further, in the present invention, the volume control means can set an upper limit of a volume adjustment amount in advance. According to the present invention, it is possible to set an upper limit on the volume adjustment amount, prevent a situation in which the volume increases further with an increase in noise and give fear, and also prevent the occurrence of distortion due to saturation of the sound output.

According to the present invention, there is provided a parameter storage means for setting and storing a plurality of sets of parameters respectively defining the operation states of the sound source signal processing means, the vehicle interior signal processing means, and the volume control means, The apparatus further includes parameter selection means for selecting operating parameters of the sound source signal processing means, the vehicle interior signal processing means, and the volume control means by selecting parameters stored in the means.
According to the present invention, for example, by preparing and storing parameters necessary for digital signal processing in advance for a vehicle that may be mounted, parameters are selected according to the vehicle, and an appropriate operation state is selected. Can be switched.

The present invention further comprises a speaker for sound reproduction arranged at a plurality of places in the vehicle interior, and a position selector for selecting a sound field reproduced from the speakers at the plurality of places in accordance with a listening position. , The sound field control means,
In accordance with the sound field selected by the position selector, the sound volume reproduced from the speakers at the respective positions is controlled. According to the present invention, the reproduction volume from each speaker can be controlled in conjunction with the sound field in the vehicle interior selected by the position selector, and the volume can be adjusted regardless of the listening position.

Also, in the present invention, the sound source signal processing means includes:
Digital signal processing for deriving a reference signal is performed after all of the acoustic characteristic change processing for the sound source signal to be reproduced is completed. According to the present invention,
When the parameters are changed in the sound characteristic change processing of the sound source signal, the effect is reflected in the sound output to the vehicle interior, and the vehicle is processed by the vehicle interior signal processing means from the vehicle interior sound input means for detecting the sound signal from the vehicle interior. It is also reflected in the room signal.
Since the influence of the change is reflected also on the input signal to the sound source signal processing means, it is not necessary to change the parameters for digital signal processing for deriving the reference signal.

Further, in the present invention, the vehicle interior sound input means is provided with a microphone not only for detecting the vehicle interior sound signal but also for other uses. According to the present invention, a microphone for detecting an acoustic signal in a vehicle compartment can be switched to another use, for example, a hands-free car telephone, an input microphone for a voice recognition device, or the like.

Further, in the present invention, the vehicle interior sound input means includes a microphone integrally formed with an illumination lamp on a ceiling portion of the vehicle interior for detecting a vehicle interior sound signal. According to the present invention, since the microphone is arranged on the ceiling of the passenger compartment, the acoustic signal in the passenger compartment can be appropriately detected. By being formed integrally with the illumination lamp, the microphone can be stably supported, and can be fixed without impairing the aesthetic appearance in the vehicle interior.

[0034]

FIG. 1 shows an outline of an electrical configuration related to a noise-sensitive automatic volume control device 1 as one embodiment of the present invention. The noise-sensitive automatic volume control device 1 controls the main control by a digital signal processor (hereinafter referred to as “DS”).
P ") by digital operation processing. Based on an input signal from the vehicle interior sound input device 3,
The DSP 2 calculates a comparison signal by digital signal processing of the vehicle interior signal processing means 4. The comparison signal is generated by the sound source signal processing unit 5.
Is compared with the reference signal calculated by the digital signal processing of
It is detected as a noise amount in the arithmetic processing by the sound volume control means 6, and control for adjusting the sound volume is performed. Volume control means 6
Is also adjusted according to the road information from the navigation device 7.

The noise-sensitive automatic volume control device 1 is ON / O
It can be switched between ON state and OFF state by the FF switching means 8, can be set by inputting various parameters by the adjusting means 9, and is incorporated in the on-vehicle audio device 10 which reproduces sound in the cabin of the automobile. When sound reproduction of the program source from the sound source 11 is performed in the vehicle cabin, the sound volume adjustment for correcting the amount of noise is digitized and performed. By digitizing the control, it is possible to increase the detection accuracy of the noise amount, adjust parameters such as an arbitrary time constant and a method of correcting the volume, and perform an automatic volume adjustment without a sense of discomfort in terms of hearing.

FIG. 2 is a diagram showing the on-vehicle audio device 10 shown in FIG.
2 shows the internal configuration of FIG. The sound source 11 includes a compact disk (abbreviated as “CD”), a cassette tape (abbreviated as “CS”),
Alternatively, a broadcast or the like is used as a source. Sound source 11
Output from the DSP as a digital signal source signal
2 is input. If the source is an analog signal, the signal is converted from analog to digital (hereinafter abbreviated as “A / D”).
The signal is converted into a digital signal using a converter and input.
The DSP 2 includes an auto volume loudness circuit 12 and a front, rear and woofer fixed equalizer (high-pass filter,
Low-pass filter, band-pass filter) circuit 13f,
13r and 13w are formed. The sound source signal input to the DSP 2 is a left and right two-channel stereo signal,
In the automatic volume and loudness circuit 12, volume adjustment and loudness correction for preventing masking at a low volume are performed for each channel. Outputs from the auto volume and loudness circuit 12 are output from fixed equalizer (high-pass filter, low-pass filter, band-pass filter) circuits 13f and 13 provided for each of the left and right channels.
r, 13w, which are divided into front, rear and woofer, respectively.
"D / A" is input to the converter 14,
It is converted to an analog signal.

The output from the D / A converter 14 is input to the electronic volume 15. The electronic volume 15
This volume adjusts the volume based on the operation of the user who listens to the audio signal reproduced in the vehicle interior, and can change the degree of attenuation of the input signal according to the electrical control input. A manually operable variable resistor can also be used. The output of the electronic volume 15 is power-amplified by the power amplifier 16 and drives the speaker 17 to be reproduced in the passenger compartment. In the present embodiment, the speakers 17 for both the left and right channels are arranged on the front and the rear, respectively, and the woofer for low-frequency sound is also provided for the speakers 17
It is arranged as. Although various forms are conceivable for the arrangement of the speaker 17 in the vehicle cabin, the basic concept of adjusting the volume corresponding to noise is the same.

The acoustic signal in the cabin is received by the microphone 18 of the cabin acoustic input device 3. The acoustic signal includes a source component sound-reproduced into the vehicle interior by the speaker 17 and a noise component generated inside and outside the vehicle interior. The acoustic signal captured by the microphone 18 is amplified by the microphone amplifier 19, and is amplified by the A / D converter 2.
The signal is converted into a digital signal by 0 and input to the DSP 2 as a vehicle interior signal.

The output from the auto volume and loudness circuit 12 is subjected to digital signal processing by the sound source signal processing means 5. In the sound source signal processing means 5, the DSP 2
Band-pass filter circuit 21 based on program operation of
s, the vehicle interior transfer characteristic equalizer circuit 22, the gain adjustment circuit 23, the rectifier circuit 24s, the gain adjustment circuit 25s, and the integration circuit 26s are equivalently included. In the band-pass filter circuit 21s, the frequency band of the sound source signal is set to, for example, 4
Limit to 0-400 Hz. Are sequentially performed and input to the subtraction circuit 27. The vehicle interior transfer characteristic equalizer circuit 22 eliminates a difference in acoustic characteristics between the sound signal in the vehicle interior and the sound source signal input to the microphone 18 in a noise-free state. In the gain adjustment circuit 23,
The amplification gain is changed according to the operation of the electronic volume 15. If the gain adjustment is not performed, even if the volume in the passenger compartment increases due to the operation of the electronic volume 15, it is treated as an increase in noise, and the auto volume / loudness circuit 12 performs control to increase the volume. Is generated.

The vehicle signal processing means 4 also has a band-pass filter circuit 21n based on the program operation of the DSP 2,
Rectifier circuit 24n, gain adjustment circuit 25n, and integration circuit 26n are included. The frequency band of the bandpass filter circuit 21n is basically the same as that of the bandpass filter circuit 21s of the sound source signal processing circuit 5. The rectifier circuit 25n
Together with the rectification circuit 25s, the vehicle compartment signal and the sound source signal are respectively rectified. The gain adjustment circuit 25n, together with the gain adjustment circuit 25s, performs fine adjustment of the gain for eliminating the difference between the output levels from the vehicle interior signal processing means 4 and the sound source signal processing means 5 when there is no noise. Integration circuit 26n
Together with the integration circuit 26s smoothes the rectified and gain-adjusted output, and makes the comparison signal and the reference signal change smoothly. Since the integration circuits 26n and 26s are realized by digital signal processing, it is possible to easily realize a time constant of several seconds, which is practically impossible with an analog circuit.

The comparison signal and the reference signal from each of the integration circuits 26n and 26s are input to the volume control means 6, respectively. The volume control means 6 includes a subtraction circuit 27 and a noise detection circuit 28 based on the program operation of the DSP 2. The subtraction circuit 27 subtracts the output level of the reference signal from the output level of the comparison signal. Noise detection circuit 28
Calculates the noise amount based on the level difference from the subtraction circuit 27.

The noise amount calculated by the volume control means 6 is given to the selection circuit 29. The selection circuit 29 determines whether the noise amount exceeds a preset threshold value,
Select an operation coefficient of the auto volume and loudness circuit 12 prepared in advance in the parameter table 30,
Controls volume and loudness correction characteristics. The output from the auto volume loudness circuit 12 is
By 1, the signals for both the left and right channels are added and the power is averaged.

The parameter table 30 stores various parameters that can be changed by the program operation of the DSP 2 as a combination pattern, and can be arbitrarily called.
A combination of parameters optimally set for each vehicle that may be equipped with the noise-sensitive automatic volume control device 1 is stored in advance, and can be switched by a hardware switch.
The wiring pattern on the circuit board can be switched by a jumper line, and the result can be input and selected by software.
In addition, a signal for selection can be externally provided via a communication function such as RS-232C. With such a selectable configuration, the optimum parameters can be easily called for each vehicle, and D is changed every time the mounted vehicle changes.
The trouble of rewriting the coefficient for the program operation of SP2 can be saved.

The electronic volume 15 is a dedicated semiconductor IC
The volume of the sound source signal reproduced in the vehicle compartment is increased or decreased according to a control signal corresponding to an operation from a user. The control signal corresponding to the operation position of the electronic volume 15 is detected by the microcomputer 32.
The microcomputer 32 adjusts the gain of the gain adjustment circuit 23 of the sound source signal processing means 5 according to the operation on the electronic volume 15. That is, the electronic volume 15
When the volume of the acoustic signal reproduced by the microphone is increased, the cabin signal input to the microphone 18 also increases, and the auto volume and loudness circuit 12 increases the reproduced volume in the same manner as when the noise increases. Is controlled. As a result, the output level of the comparison signal from the vehicle interior signal processing means 4 further increases, and a situation in which the correction for increasing the volume is repeated indefinitely may occur. If the gain of the gain adjustment circuit 23 is increased, the output level of the reference signal from the sound source signal processing means 5 is correspondingly increased, and control is performed such that the level difference from the comparison signal when there is no noise is kept at 0. be able to.

The operation input for the electronic volume 15 is performed by, for example, angularly displacing a knob or the like attached to a rotary shaft such as a rotary encoder or a variable resistor. In general, the in-vehicle audio device 10 or the like generally operates as a power ON / OFF switch when a knob is pressed in the axial direction. On such a rotating shaft, ON of FIG.
The ON / OFF control of the volume adjustment is performed by incorporating the ON / OFF switching means 8 and pressing in different directions in the axial direction.
May be switched. As the noise-sensitive automatic volume control device 1 arranged in a limited space in the vehicle interior, it is not possible to provide a configuration for inputting too many operations on the front panel or the like. Also, the front panel can be easily seen.

From the user side, for example, the adjusting means 9 of FIG.
The time constant and the correction amount of the sound volume can also be adjusted using, for example, the above. The time constant may be increased if the user prefers a slow change, and the time constant may be decreased if the user prefers a sensitive response. The correction amount can also reflect the user's preference. Further, the control of the volume adjustment is performed by the ON / OFF switching means 8 to be ON or OFF.
Can be switched to The control can be switched according to the needs of the user. Further, when the operation on the adjusting means 9 is not performed for a certain period of time, the control may be switched on, or when the operation position is on the minimum side, the control may be switched off. Furthermore, the control can be turned on if the operation for adjusting the volume of the electronic volume 15 is not performed for a certain period of time. With such a configuration, control switching can be performed without intentionally operating the ON / OFF switching means 8. Further, when the user sets a desired volume and continues sound reproduction, the volume adjustment for noise sensitivity is automatically performed based on the volume.

FIG. 3 shows an example of a state in which the noise-sensitive automatic volume control device 1 shown in FIGS. The noise-sensitive automatic volume control device 1 is disposed on the console in front of the vehicle compartment 41 together with the navigation device 7. A front speaker 17f is provided in front of the front seat 42.
Are arranged on the left and right, and the rear speaker 17r is arranged on the left and right behind the rear seat 43. Near the front of the door 44,
Woofers 17w are arranged on the left and right. Power amplifier 16
Is installed in a trunk room at the rear of the vehicle 40.
The microphone 18 is integrated with a room lamp 45 arranged on the ceiling for illumination in the passenger compartment 41. Thus, the microphone 18 can be stably and reliably installed on the ceiling without deteriorating the beauty of the interior of the passenger compartment 41. If the connector of the wiring line for the microphone 18 is formed integrally with the connector for the room lamp 45, the mounting becomes easy. Microphone 18
Can be incorporated in the noise-sensitive automatic volume control device 1. Further, the microphone 18 may be integrated with the noise-sensitive automatic volume control device 1.

The microphone 18 can be used for other purposes. For example, it can be switched and used as a hands-free telephone or a microphone for voice recognition. It can also be used for input of an active noise suppression device for keeping the interior of the vehicle compartment 41 quiet.

The navigation device 7 can use the communication function to obtain road information on the road on which the vehicle 40 is traveling. For example, when the vehicle 40 is traveling on a tunnel or an expressway, noise such as road noise and wind noise increases, so that the volume is controlled to increase. When the vehicle is involved in traffic congestion, the running speed is reduced, so that the volume is controlled to be attenuated.

FIG. 4 shows the bandpass filter circuit 2 of FIG.
The measurement result for determining the lower limit of the pass frequency band of 1n and 21s is shown. Each graph shows the low cutoff frequency at 20 Hz, 25 Hz, 31.5 Hz, and 40H.
The noise levels in the vehicle cabin when low-cut filters of z, 50 Hz and 63 Hz are used are shown. The microphone for measurement (MIC) is located at the center room lamp (ROOF) in the center of the ceiling of the cabin,
The measurements are taken at two places, the center console (CONSOLE) on the driver's seat side. The window (WINDOW), which is the window of the passenger compartment, is in the closed state (C
(LOSE) and open (OPEN). In a relatively low speed range from idling to 40 km / h, in a frequency band lower than 40 Hz, there is no remarkable difference in sound pressure level when driving at higher speeds, and wind noise and road noise increase in hearing. I can't respond to what I feel. In order to make it easier to distinguish between the idling state and the running state, it is possible to detect noise that matches the audibility by cutting the low frequency range of less than 40 Hz rather than taking in the entire band.

Regarding the upper limit of the pass frequency band of the band-pass filter circuits 21n and 21s, 200 to 1.6 kHz
If it is set between, there is no change in the noise level. The larger the amount of information, the better, and the equalization circuit 2
In consideration of not increasing the number of correction points in Step 2, a frequency of about 400 Hz is appropriate.

FIG. 5 shows an equalizer circuit 2 for a vehicle interior transfer characteristic.
2 shows the principle effect of using. FIG. 5A shows an example of a sound source signal output from the rectifier circuit 24s when the correction is not performed based on the vehicle interior transfer characteristic, and FIG. 5B shows an integration circuit 26s.
The output of FIG. 5C shows the cabin signal output from the rectifier circuit 24n, and FIG. 5D shows the output of the integration circuit 26n. FIG. 5E shows the difference between the integration circuits 26s and 26n shown in FIGS. 5B and 5D. This difference cannot be eliminated only by adjusting the gain, and the noise amount may be erroneously detected. This difference is mainly due to the transfer function of the vehicle interior, and the transfer function can be applied to the sound source signal by using the vehicle interior transfer characteristic equalizer circuit 22 to eliminate the difference. Further, the difference can be similarly eliminated by applying an inverse function of the transfer function of the vehicle compartment to the vehicle compartment signal.

FIG. 6 shows the operation of the selection circuit 29 of FIG. When the noise amount is calculated by the noise amount detection circuit 28 in step a0, the threshold level 1 which is the first threshold is subtracted in step a1. When the result is minus, that is, when the threshold level 1 is larger than the noise amount, a combination of G1 as a gain and L1 as a loudness characteristic is selected from the parameter table 30 in step a1p, and given to the auto volume and loudness circuit 12 as a coefficient. . If the result of the subtraction in step a1 is positive, the threshold level 2 which is the second threshold is subtracted in step a2. If the result is negative, the gain is G2 and the loudness is L2 in step a2p.
Select the combination of Similarly, in step aM, the threshold level M that is the Mth threshold value is subtracted,
Step aMp, depending on whether the result is negative or positive
Alternatively, in step aNp, GM or G
N and LM or LN are selected as N and loudness, respectively. Since the volume correction amount of the automatic volume and loudness circuit 12 is adjusted stepwise using the coefficients stored in the parameter table 30 in advance, the program steps as the DSP 2 are simplified as compared with the case where the correction amount is continuously adjusted. Can be

In the volume adjustment by changing the coefficient of the auto volume and loudness circuit 12, since a sudden change may cause a sense of incongruity, it is preferable to provide a time constant. Auto volume loudness circuit 12 is also D
Since it is realized by the program operation of SP2, it is easy to change the time constant with a time constant of about several seconds. When the volume is instantaneously adjusted when the noise amount exceeds the threshold value, it is easy for the user to feel uncomfortable in hearing. By slowly adjusting the volume, natural control can be realized. Furthermore, if the time constant can be set independently when the sound volume rises and when the sound volume drops, natural control can be realized, for example, by setting the time constant when rising to be longer and the time constant when lowering to be shorter. can do. The reason is that a human can detect and react sensitively when the sound volume increases, but slows down when the sound volume decreases.

FIG. 7 shows a partial configuration of a noise-sensitive automatic volume control device according to another embodiment of the present invention. Parts corresponding to the embodiment of FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. The speaker arrangement as shown in FIG.
The position selector 50 is provided so that an optimum sound field at a specific position in the area 1 is formed with good sound quality.
The position selector 50 is provided for each fixed equalizer 1.
The coefficients are given to 3f, 13r, and 13w, and the coefficients are transferred and given to auto volume loudness circuits 51f, 51r, and 51w provided independently for each channel. Auto volume and loudness circuits 51f and 5
Coefficients given to 1r and 51w are selected and given by a front selection circuit 52f, a rear selection circuit 52r, and a woofer selection circuit 52w based on the noise amount from the noise amount detection circuit 28. Therefore, in conjunction with the position selector 50, it is possible to provide an optimum sound field and sound quality at a specific position in the vehicle compartment 41 and obtain an effect of volume correction.

Also, the fader 51 can be controlled by the volume control means 6 as a second electronic volume so that the auto volume and loudness circuit 12 is not used. By using such independent volume adjustment means, the load on the software of the operation program of the DSP 2 is reduced. On the other hand, if the auto volume and loudness circuit 12 is used, there is no need to provide an external volume control means, and the correction amount of the volume is added to the volume corresponding to the operation position of the electronic volume 15 when the control is OFF. By performing the control, there is no need to provide an independent volume control means, and the hardware configuration is simplified.

FIG. 8 shows, as still another embodiment of the present invention, a test signal generating circuit 60 for generating a test signal such as white noise by a changeover switch 61.
A configuration in which the sound source 11 and the sound source 11 are switchably added is shown. Parts corresponding to the embodiment of FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. The transfer characteristic used in the vehicle interior transfer characteristic equalizer circuit 22 in FIG. 2 is a frequency characteristic of an acoustic signal detected by the microphone 18 by reproducing white noise from the speakers 17f, 17r, and 17w in the vehicle interior 41 in FIG. Can be determined by analyzing The white noise is a signal in which an acoustic signal having a uniform amplitude is randomly generated over a wide frequency band, and the acoustic signal detected by the microphone reflects acoustic transfer characteristics in the vehicle interior 41. As a test signal, a single sine wave whose frequency continuously changes can be used.

The test signal is reproduced when there is no noise or when there is very little noise, and the vehicle interior transfer characteristic equalizer circuit 22 and the gain adjustment circuits 25s and 25n are adjusted so that the level difference between the reference signal and the comparison signal does not occur. This makes it possible to realize a state in which appropriate noise correction can be performed including the acoustic characteristics of the vehicle interior. The vehicle interior transfer characteristics change depending on the arrangement of the occupants in the vehicle interior 41, and the speakers 17f, 17f.
It also changes depending on the arrangement and orientation of r and 17w. If the test signal generation circuit 60 is mounted, it is possible to perform a sound volume adjustment accurately adapted to the vehicle interior transfer characteristics even when the vehicle 40 is changed.

In each of the embodiments described above, when performing the correction for increasing the sound volume, it is preferable to link the compressor processing for compressing the dynamic range between the maximum output level and the minimum output level of the sound source signal. In the power amplifier 16 and the like, the output has an upper limit, and when the input voltage level rises due to the volume adjustment, the output level is immediately saturated on the high-level high-output side, and the distortion increases to deteriorate the sound quality. As a compressor process that uses the amount of noise as a parameter, the volume correction is increased on the low-level, low-output side to prevent masking due to noise, and the output is compressed by reducing the volume correction on the high-level, high-output to reduce sound quality degradation. Can be prevented.

In the volume correction, an upper limit may be given to the control for increasing the volume. If the upper limit is set, the reproduction output of the sound source signal also increases with the increase in noise, the sound pressure level in the vehicle interior increases, and the power amplifier 16
It is possible to prevent the sound cracking due to the saturation of the sound and the state that gives a feeling of discomfort or fear. Further, when the volume set in the electronic volume 15 is 0 or a very small volume, it is preferable to turn off the volume control. When the volume control is ON, if a high-level sound source signal is suddenly input in a state where the correction amount of the volume is large, the time constant of the change of the correction amount is large, so that the sound is reproduced at an extremely high volume. It is.

The operation of switching off the volume control can be performed by turning off the input from the microphone 18. This is equivalent to a state in which there is no noise, and the sound volume set by the electronic volume 15 can be gradually restored according to the large time constant of the integration circuit 26n. Further, if the coefficient before the start of control is transferred to the DSP 2 or the temporary data of the integration circuits 26s and 26n is cleared, the state before the start of control can be instantaneously returned.

The position where the sound source signal processing means 5 takes out the sound source signal is preferably after all the frequency characteristic changing processes such as various equalizers are completed. If there is a change in the equalizer, the frequency distribution characteristics of the signal reproduced in the vehicle compartment change, and the vehicle compartment signal also changes. If the sound source signal similarly changes, it is not necessary to change the parameters.

[0063]

As described above, according to the present invention, the adjustment of the sound volume corresponding to the noise amount can be automatically performed by digital signal processing. Therefore, the control accuracy can be improved without the influence of the variation of the components constituting the electronic circuit as in the case of the analog signal processing. Also,
Since the operating state can be changed by changing the parameters of the signal processing without replacing parts, the degree of freedom of the operating state is large, and it is easy to set appropriate parameters and operate as necessary. is there. In addition, since the sound source signal processing means performs an arithmetic process based on the transfer function in the vehicle compartment, the level of the comparison signal and the reference signal in the absence of noise can be matched to make the difference zero. Further, the volume of listening to the sound source signal reproduced in the vehicle cabin can be adjusted by operating the volume operation means from the user side. Even if an operation is performed on the volume operation means, it is possible to control the level difference between the reference signal and the comparison signal so that the level difference always becomes 0 in a state where there is no noise. It is possible to prevent the control from falling into an infinitely repeating state.

Further, according to the present invention, it is possible to detect an appropriate amount of noise by limiting the frequency band of the sound signal and the sound source signal in the vehicle cabin detected by the cabin signal processing means and the sound source signal processing means. it can.

[0065]

Further, according to the present invention, since the integration operation is performed by digital signal processing, the integration operation corresponding to a long time constant that cannot be realized by analog signal processing can be easily performed. For example, in an analog integrating circuit, if the time constant is set to several seconds, a large-capacity capacitor is prepared and the output level is reduced, so that the practicality is lost. Digital signal processing enables long-term integration, for example, a few seconds, to set the time constant, so that the control waveform of the volume control is smoothed for instantaneous noise changes, and the volume does not cause discomfort in the sense of hearing. Control can be performed.

Further, according to the present invention, the time constant of the integral operation can be adjusted by the user's operation, so that the state of the volume control is adjusted according to the preference of the user who listens to the sound reproduction in the passenger compartment. be able to. If the time constant is long, loose control is performed, and if the time constant is short, sharp control is performed.

[0068]

Further, according to the present invention, the sound reproduction volume is controlled when the noise amount exceeds a preset threshold value, and is not performed when the noise amount does not exceed the threshold value. It is possible to reduce the number of program steps for digital signal processing as compared with the case where volume control is performed inclusively.

Further, according to the present invention, the road information on which the vehicle is traveling is detected, and the volume for sound reproduction is controlled in accordance with the detected road information. , Appropriate volume control can be performed.

Further, according to the present invention, the level difference between the maximum signal level and the minimum signal level is compressed by the compressor means in conjunction with the amount of noise, so that sound quality deterioration due to saturation of the sound source signal can be prevented. Also, when the input level of the sound source signal is low, the output level is set higher than the input level, so that masking of the sound source signal due to noise can be avoided and sound reproduction can be performed without impairing the dynamic range of the sound source signal. it can.

Further, according to the present invention, the output of the reference signal and the output of the comparison signal are adjusted based on the signal generated from the test signal generating means so as to be equal.
The volume control can be appropriately performed. Also, acoustic characteristics such as frequency characteristics can be automatically adjusted.

Further, according to the present invention, since the control amount of the sound volume can be adjusted by the operation input from the user, the correction amount is adjusted according to the preference of the user who reproduces and listens to the sound source signal in the passenger compartment. be able to.

Further, according to the present invention, the control for automatically adjusting the volume according to the noise level can be switched ON or OFF according to the user's need.

Further, according to the present invention, since the volume control is performed based on the volume corresponding to the operation position of the volume operation means at the time when the volume control corresponding to the noise amount is turned on, the user's preference can be obtained. Sound reproduction can be continued while ensuring a corresponding volume for noise.

According to the present invention, the volume is adjusted so as to increase the volume in accordance with the amount of noise, based on the operation position of the volume operation means when the control is switched to ON. Automatic adjustment of the volume corresponding to the amount of noise can be performed without using any means.

Further, according to the present invention, the control for automatic volume adjustment can be switched ON or OFF by performing a predetermined operation on the volume operation means. Control ON or O
There is no need to provide control operation means for switching to the FF, and the volume control means can also be used.

Further, according to the present invention, once the user's favorite volume is set, the user does not perform any operation on the volume control means. Sound reproduction can be continued.

Further, according to the present invention, when the sound volume operation means is operated to the lower sound volume side, the control of the sound volume corresponding to the noise amount is switched to OFF, so that a loud sound source signal is suddenly input. Since the volume of sound reproduced in the vehicle compartment is low, control for increasing the volume is performed, and it is possible to avoid a situation where the volume is reproduced at a very high volume.

Further, according to the present invention, by stopping the operation of the vehicle interior sound input means, it is possible to perform switching without a sense of incongruity so that a sudden change in volume does not occur.

Further, according to the present invention, the control amount for each threshold value is set to 0, the threshold value is set to a very high value, the level coefficient before integration is set to -∞, and the state before the volume control for the noise amount is started. , The control can be quickly switched to OFF.

Further, according to the present invention, since the sound volume processing means adjusts the sound volume of the sound source signal to be reproduced by digital signal processing, circuits and components for independent sound volume adjustment become unnecessary, and the electric configuration is reduced. It can be simplified.

Further, according to the present invention, since the volume control is performed by the independent volume control means, the configuration of software for digital signal processing by the volume control means can be simplified.

Further, according to the present invention, since the upper limit is set for the volume adjustment amount, it is possible to prevent a situation in which the volume increases further with an increase in noise and gives fear, and distortion occurs due to saturation of the sound output. Can be prevented.

According to the present invention, parameters required for digital signal processing are prepared and stored in advance, so that parameters can be selected according to, for example, a vehicle and easily switched to an appropriate operation state. it can.

According to the present invention, the sound volume can be adjusted independently of the listening position in conjunction with the sound field in the vehicle compartment selected by the position selector.

According to the present invention, even if the parameters are changed in the process of changing the acoustic characteristics of the sound source signal, it is not necessary to change the parameters in the digital signal processing for deriving the reference signal.

Further, according to the present invention, a microphone for detecting an acoustic signal in a vehicle compartment is switched to another use, for example, a hands-free car telephone, an input microphone for a voice recognition device, etc., and is effectively used. Can be.

Further, according to the present invention, since the microphone is arranged on the ceiling of the passenger compartment, the acoustic signal in the passenger compartment can be appropriately detected. By being formed integrally with the illumination lamp, the microphone can be stably supported, and can be securely fixed without impairing the aesthetic appearance in the vehicle interior.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a schematic electrical configuration of an embodiment of the present invention.

FIG. 2 is a block diagram showing an electrical configuration of the on-vehicle audio device 10 of FIG.

FIG. 3 is a simplified plan view showing a state in which the noise-sensitive automatic volume control device 1 of FIG. 1 is mounted on a vehicle.

FIG. 4 is a graph showing measurement results of noise in a vehicle cabin.

FIG. 5 is a graph showing the necessity of the vehicle interior transmission equalizer circuit 22 of FIG. 2;

FIG. 6 is a flowchart illustrating an operation of the selection circuit 29 of FIG. 2;

FIG. 7 is a partial block diagram showing a part of another embodiment of the present invention.

FIG. 8 is a block diagram showing a schematic electrical configuration of still another embodiment of the present invention.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 noise-sensitive automatic volume control device 2 DSP 3 vehicle interior sound input device 4 vehicle compartment signal processing means 5 sound source signal processing means 6 volume control means 7 navigation device 8 ON / OFF switching means 9 adjustment means 10 in-vehicle audio device 11 sound source 12 , 51f, 51r, 51w Auto volume and loudness circuit 15 Electronic volume 17, 17f, 17r, 17w Speaker 18 Microphone 21s, 21n Bandpass filter circuit 22 Vehicle interior transfer characteristic equalizer circuit 23, 25s, 25n Gain adjustment circuit 26s, 26n Integration Circuit 27 Subtraction circuit 28 Noise level detection circuit 29 Selection circuit 30 Parameter table 32 Microcomputer 40 Vehicle 41 Vehicle cabin 45 Room lamp 50 Position selector 52f Front selection circuit 52r Rear selection circuit 5 w woofer selection circuit 60 test signal generating circuit

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-7-46069 (JP, A) JP-A-6-334457 (JP, A) JP-A-6-303063 (JP, A) JP-A-7-460 30347 (JP, A) Japanese Utility Model Showa 57-182911 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) H03G 3/32

Claims (26)

(57) [Claims] 1. A noise-sensitive automatic volume control device for automatically adjusting the volume of sound reproduced in a vehicle compartment in accordance with the amount of noise in the vehicle compartment so as to make it easy to hear. Volume control means for performing an operation for adjusting the reproduction volume, and a sound source signal to be reproduced as a digital signal,
Sound source signal processing for calculating a sound source signal based on a vehicle interior transfer function and responding to an operation on the sound volume operation means, wherein a gain is controlled in accordance with a reproduction sound volume, and a reference signal for noise level detection is derived. Means for detecting an acoustic signal in the passenger compartment, converting the digital signal into a digital signal, and inputting the digital signal; and performing digital signal processing on the audio signal input by the audio input means in the passenger compartment to detect a noise amount. A vehicle signal processing means for deriving a comparison signal of the following; and, in response to outputs from the sound source signal processing means and the vehicle signal processing means, a noise amount is detected as a difference of the comparison signal with respect to the reference signal, and a volume for sound reproduction is determined. A noise-sensitive automatic volume control device, comprising: a volume control means for controlling the volume. 2. The noise-sensitive automatic volume control according to claim 1, wherein the vehicle compartment signal processing unit and the sound source signal processing unit limit the frequency bands of the detected sound signal and the sound source signal in the vehicle compartment. apparatus. 3. The noise-sensitive automatic volume control according to claim 1, wherein the sound source signal processing means and the vehicle interior signal processing means perform integration processing on the reference signal and the comparison signal to derive the reference signal and the comparison signal, respectively. apparatus. 4. The noise-sensitive automatic volume control device according to claim 3, wherein a time constant in the integration operation processing can be adjusted by an input operation. 5. The volume control unit according to claim 1, wherein the volume control unit controls the volume of the sound to be reproduced when the detected noise amount exceeds a preset threshold. Noise sensitive automatic volume control device. 6. The volume control based on the threshold value is performed with a predetermined time constant.
The described noise-sensitive automatic volume control device. 7. A vehicle comprising: road information detection means for detecting road information on which a vehicle is traveling; wherein the sound volume control means controls the sound reproduction sound volume according to the detected road information. The noise-sensitive automatic volume control device according to claim 1. 8. A maximum signal level of a sound source signal to be reproduced in response to a noise amount calculated by a difference between a reference signal of the volume control means or the sound source signal processing means and a comparison signal of the vehicle interior signal processing means. The noise-sensitive automatic adjusting device according to any one of claims 1 to 7, further comprising a compressor means for controlling a level difference between the signal level and the minimum signal level so as to be reduced in conjunction with a noise amount. 9. A test signal generating means, wherein the sound source signal processing means and the vehicle interior signal processing means have frequency characteristics and output levels of a reference signal and a comparison signal respectively derived based on outputs from the test signal generating means. The noise-sensitive automatic volume control device according to any one of claims 1 to 8, wherein the gains are respectively adjusted so that? 10. The noise-sensitive automatic volume controller according to claim 1, wherein a control amount of the volume by the volume controller is adjustable by an operation input. 11. An ON / OF switch for automatically turning on or off control for automatically adjusting the volume of sound reproduced in a vehicle compartment.
11. The noise-sensitive automatic volume control device according to claim 1, further comprising an F switching unit. 12. A volume control means for performing an operation for adjusting a reproduction volume of a sound source signal reproduced in a vehicle cabin, wherein said volume control means includes an ON / OFF switching means which is ON.
12. The noise-sensitive automatic volume control device according to claim 11, wherein the control is performed based on a volume corresponding to an operation position of the volume operation means at the time when the volume is switched to. 13. A volume control means for performing an operation for adjusting a reproduction volume of a sound source signal reproduced in a vehicle cabin, wherein said ON / OFF switching means is ON.
12. The noise-sensitive automatic volume control device according to claim 11, wherein control is performed by adding a control amount based on a noise signal to a volume based on an operation position of the volume operation means when the mode has been switched to. 14. The apparatus according to claim 1, wherein a control for automatically adjusting the volume of sound reproduced in the vehicle compartment can be switched on or off by performing a predetermined operation on said volume operation means. Noise sensitive automatic volume control. 15. The noise-sensitive automatic volume control device according to claim 14, wherein the control is switched to ON when the volume control means is not operated for a predetermined time or more. 16. When the volume operation means is operated to a lower volume side than a predetermined operation state, the control is turned off.
15. The noise-sensitive automatic volume control device according to claim 14, wherein the device is switched to F. 17. The control for automatically adjusting the volume is OFF.
The noise-sensitive automatic volume control device according to any one of claims 11 to 16, wherein the operation of the vehicle interior sound input means is stopped when the mode is switched to (1). 18. The control for automatically adjusting the volume is OFF.
When is switched to, in order to set the volume for the noise amount by the volume control means to the state before the control start,
11. The method according to claim 11, wherein any of the control amounts provided for each threshold value is set to 0, all the threshold values are set to a very high level, and the level coefficient before integration is set to -∞. 16. The noise-sensitive automatic volume control device according to any one of 16. 19. The apparatus according to claim 1, further comprising a volume processing unit that adjusts a volume of a sound source signal reproduced by digital signal processing in response to a noise amount from the volume control unit. 2. The noise-sensitive automatic volume control device according to item 1. 20. An apparatus according to claim 1, further comprising independent volume adjusting means for adjusting the volume of a sound source signal reproduced by digital signal processing in response to the amount of noise from said volume control means. 19. The noise-sensitive automatic volume control device according to any one of 18. 21. An apparatus according to claim 1, wherein an upper limit of a volume adjustment amount can be set in said volume control means in advance.
21. The noise-sensitive automatic volume control device according to any one of items 20 to 20. 22. Parameter storage means for setting and storing a plurality of sets of parameters respectively defining operation states of the sound source signal processing means, the vehicle compartment signal processing means and the volume control means, and storing the parameter storage means in the parameter storage means. The noise according to any one of claims 1 to 21, further comprising parameter selection means for selecting operating parameters to switch operation states of the sound source signal processing means, the vehicle interior signal processing means, and the volume control means. Sensitive automatic volume control. 23. A sound reproducing speaker disposed at a plurality of places in the vehicle interior, and a position selector for selecting a sound field reproduced from the plurality of speakers in accordance with a listening position. 23. The noise according to any one of claims 1 to 22, wherein the field control means controls the volume of sound reproduced from a speaker at each position in conjunction with the sound field selected by the position selector. Sensitive automatic volume control. 24. The sound source signal processing means performs digital signal processing for deriving a reference signal after all sound characteristic change processing for a sound source signal to be reproduced is completed. 24. The noise-sensitive automatic volume control device according to any one of 1 to 23. 25. The noise according to any one of claims 1 to 24, wherein the vehicle interior sound input means includes a microphone not only for detecting a vehicle interior sound signal but also for other purposes. Sensitive automatic volume control. 26. The apparatus according to claim 1, wherein the vehicle interior sound input means includes a microphone integrally formed with an illumination lamp on a ceiling portion of the vehicle room for detecting a vehicle interior sound signal. The noise-sensitive automatic volume control device according to any one of the above.