JP2007104407A - Audible signal processing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To increase sound volume feeling even when performing a reproduction by using a small-diameter speaker or the like without unnecessarily cutting a low-pitched sound and increasing the distortion feeling of a reproduced sound. <P>SOLUTION: In the audible signal processing apparatus 100, the dynamic range of a low-pitch signal S103 is compressed by using a low-pitch signal compressor unit 103 on the basis of a result measuring the power of an input audible signal S101 using an input signal power calculation unit 101. A compressed low-pitch signal S105 and a middle-pitch/high-pitch signal S104 are composited by a composition unit 104, further, the dynamic range of a composite signal is then compressed by a composite signal compressor unit 106, and the compressed signal is amplified by an amplifier unit 107 thereafter. Thus, the low pitch is appropriately cut while considering entire volume, the influence caused by the dynamic range compression of middle and high pitches is suppressed to a minimum and average power can be amplified, thereby obtaining an audible signal optimal for performing the reproduction by the small-diameter speaker. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an acoustic signal processing apparatus used for a device that sounds an acoustic signal with a small-diameter speaker such as a mobile phone.

  In recent years, portable small-sized sound reproduction devices such as mobile phones with a music reproduction function are becoming widespread. However, it is difficult to mount a large-diameter speaker in a cellular phone or the like because of the size, and it is difficult to reproduce a low frequency sound such as a so-called bass, that is, a low frequency sound. Even if the bass sound is forcibly reproduced, the speaker such as a cellular phone is hardly audible in terms of audibility, and as a result, the level of the input signal exceeds the upper limit of the ability of the speaker, causing a sense of distortion. In addition, it is difficult to produce a loud sound due to limitations of the speaker and the housing.

  FIG. 11 is a block diagram showing a configuration example of a conventional acoustic signal processing apparatus. In such an acoustic signal processing apparatus 900 of the conventional example, a low-pass that cannot be reproduced by a speaker such as a mobile phone is cut by a high-pass filter (HPF) unit 901, and an acoustic signal is once transmitted by a compressor unit 902 in order to increase the volume feeling. A configuration is adopted in which compression is performed and then the overall volume is increased by the amplifier unit 903.

  In addition, although the purpose is different from the above, a configuration that uses means for separating low and middle and high sounds with a filter and controlling the volume only on the low sound side (see, for example, Patent Document 1) or divided into a plurality of frequency bands, respectively. For example, a configuration for controlling the volume (see, for example, Patent Document 2) has been proposed.

Japanese Utility Model Publication No. 2-123120 JP-A-1-198818

  However, in the conventional acoustic signal processing apparatus, by processing the input signal with a high-pass filter, the low frequency is unnecessarily cut even when the input acoustic signal is sufficiently small and can be reproduced as it is. There was a problem. Even when a method is used in which the input sound signal is divided into bands and the volume is controlled only by the low sound, since the entire sound signal level is not taken into consideration, the low sound may be cut more than necessary.

  The present invention has been made in view of the above circumstances, and can increase the volume feeling even when reproducing with a small-diameter speaker or the like without unnecessarily cutting the bass or increasing the sense of distortion of the reproduced sound. It is an object of the present invention to provide an acoustic signal processing device that can improve sound quality on hearing.

  An acoustic signal processing device according to the present invention is an acoustic signal processing device that performs predetermined gain control on an acoustic signal, an input signal power measuring unit that measures the power of the input acoustic signal, Filtering means for separating a low-frequency signal and a mid-high frequency signal in a frequency band, and gain adjusting means for multiplying the low-frequency signal by an appropriate gain based on the power of the input acoustic signal measured by the input signal power measuring means And combining means for combining the low-frequency signal whose gain has been adjusted and the middle-high frequency signal, combined signal power measuring means for measuring the power of the combined acoustic signal, and measurement by the combined signal power measuring means Compression means for compressing the dynamic range of the synthesized acoustic signal based on the power of the synthesized acoustic signal, and an amplifying unit for multiplying the compressed synthesized acoustic signal by a gain It is those with a door.

  With the above configuration, it is possible to amplify the average power of the acoustic signal while controlling the volume of the low frequency range that causes distortion when reproduced by a small-diameter speaker or the like. For this reason, it is possible to increase the volume feeling even when music or the like is reproduced with a small-diameter speaker or the like without unnecessarily cutting the bass or increasing the distortion of the reproduced sound.

  The acoustic signal processing device of the present invention is an acoustic signal processing device that performs predetermined gain control on an acoustic signal, and includes an input signal power measuring unit that measures the power of the input acoustic signal, and the input acoustic signal. Filtering means for separating a low-frequency signal and a mid-high frequency signal in a predetermined frequency band, and a gain for multiplying the low-frequency signal by an appropriate gain based on the power of the input acoustic signal measured by the input signal power measuring means Adjusting means, combining means for combining the low-frequency signal with the adjusted gain and the middle-high frequency signal, and the power of the input acoustic signal measured by the input signal power measuring means Compression means for compressing the dynamic range, and amplification means for multiplying the compressed synthesized acoustic signal by a gain are provided.

  With the above configuration, it is possible to amplify the average power of the acoustic signal while controlling the volume of the low frequency range that causes distortion when reproduced by a small-diameter speaker or the like. For this reason, it is possible to increase the volume feeling even when music or the like is reproduced with a small-diameter speaker or the like without unnecessarily cutting the bass or increasing the distortion of the reproduced sound.

  Also, the present invention is the above acoustic signal processing device, wherein the gain adjusting means includes low-frequency compression means for compressing a dynamic range of the low-frequency signal. With this configuration, the low frequency range gain can be adjusted by compressing the dynamic range of the low frequency signal.

  Moreover, this invention is said acoustic signal processing apparatus, Comprising: The said compression means shall change the various parameters of a compression process with reference to the power of the said input acoustic signal. With this configuration, various parameters of the compression process are changed according to the power of the input sound signal, and the dynamic range of the appropriate low-frequency signal can be compressed.

  Also, the present invention is the above acoustic signal processing device, wherein the gain adjusting unit multiplies a value corresponding to the power of the input acoustic signal as a gain by using preset gain information. With this configuration, the gain in the low frequency range can be adjusted by multiplying the gain corresponding to the power of the input acoustic signal.

  Further, the present invention is the above acoustic signal processing device, wherein the gain information is 1 when the power of the input acoustic signal is smaller than a first threshold value, and becomes smaller when the first threshold value is exceeded. It decreases in the direction and becomes 0 when exceeding the second threshold. With this configuration, the gain in the low sound range can be appropriately adjusted according to the power of the input acoustic signal by the gain information set based on the two threshold values.

  Further, the present invention is the above-described acoustic signal processing device, and includes at least one of a diameter of a speaker connected to the output side of the acoustic signal processing device or a shape of a housing on which the acoustic signal processing device is mounted. It is assumed that the crossover frequency when the input acoustic signal is separated into the low-frequency signal and the mid-high frequency signal can be changed according to the characteristics of the mounted device. With this configuration, it is possible to set the crossover frequency according to the characteristics of the on-board equipment and appropriately separate the input acoustic signal into a low-frequency signal and a mid-high frequency signal.

  Further, the present invention is the above acoustic signal processing device, wherein volume information related to a set volume is received from a volume adjustment unit of a mounted device on which the acoustic signal processing device is mounted, and based on the volume information, the compression unit It is assumed that compression ratio changing means for determining a parameter for adjusting the compression ratio of the dynamic range is provided, and the compression ratio is changed in conjunction with a volume adjustment function of the mounted device. With this configuration, it is possible to change the operation characteristics such as the compression ratio of the dynamic range in conjunction with the volume setting of the mounted device. Therefore, for example, when the volume setting is small, there is less possibility of distortion, so it is possible to set the compression rate low, and when the set volume is high, it is possible to set the compression rate higher. Appropriate processing operations can be performed.

  According to the present invention, it is possible to increase the volume feeling even when reproducing with a small-diameter speaker or the like without unnecessarily cutting the bass or increasing the sense of distortion of the reproduced sound, and the sound quality on hearing is improved. An acoustic signal processing device that can be improved can be provided.

  In the present embodiment, a configuration example of an acoustic signal processing device arranged to be applied to a small device such as a music playback device, an information terminal, or a mobile phone is shown.

  FIG. 1 is a block diagram showing the configuration of an acoustic signal processing apparatus according to the first embodiment of the present invention. The acoustic signal processing apparatus 100 according to the first embodiment includes an input signal power calculation unit (corresponding to an example of an input signal power measurement unit) 101 that calculates the power of an input acoustic signal, a low-frequency signal, and a medium-high signal. A filter unit (corresponding to an example of a filtering unit) 102 that separates a low-frequency signal and a low-frequency signal compressor unit (corresponding to an example of a low-frequency compressing unit as a gain adjusting unit) 103 that compresses the dynamic range of the low-frequency signal And a synthesis unit (corresponding to an example of the synthesis unit) 104 that synthesizes the low-frequency signal and the high-frequency signal, and a synthesis signal power calculation unit (corresponding to an example of the synthesis signal power measurement unit) that calculates the power of the synthesis signal. ) 105, a synthesized signal compressor unit (corresponding to an example of compression means) 106 for compressing the dynamic range of the synthesized signal, and a synthesized signal with the compressed dynamic range. (Corresponding to an example of the amplifying means) amplifier portion for the width configured by a 107. The filter unit 102 includes an LPF (low-pass filter) unit 108 and an HPF (high-pass filter) unit 109.

  The operation of the acoustic signal processing apparatus according to the first embodiment configured as described above will be described with reference to FIG. First, the power of the input acoustic signal S101 is measured and calculated by the input signal power calculator 101 to obtain input signal power information S102. The power measurement may be performed, for example, by calculating the square root after squaring the input acoustic signal.

  Next, the input acoustic signal S101 is separated by the filter unit 102 into a low-frequency signal S103 and a middle-high frequency signal S104. The signal is separated by a method in which the LPF unit 108 extracts the low frequency signal S103 and the HPF unit 109 extracts the mid-high frequency signal S104. As shown in FIG. 2, the LPF unit 108 and the HPF unit 109 at this time have characteristics that are equal to the original input acoustic signal when the outputs of each other are simply added. Here, the cut-off frequency fc in FIG. 2 is determined by the acoustic characteristics of the actually used speaker and casing. Therefore, if the cut-off frequency fc can be freely controlled, various devices can be supported. That is, the frequency characteristics of the pass band of the filter unit 102 are made variable so that the crossover frequency when the input acoustic signal is separated into the low-frequency signal and the mid-high frequency signal can be changed. Therefore, the low frequency signal can be separated appropriately. At this time, it is provided in the mounted device on which the acoustic signal processing device is mounted, and includes at least one of these, such as the diameter of the speaker connected to the output side of the acoustic signal processing device or the shape of the housing of the mounted device Change the crossover frequency according to the characteristics of the installed device.

  Next, in the low frequency signal compressor unit 103, the dynamic range of the low frequency signal S103 is compressed using the input signal power information S102 to obtain a compressed low frequency signal S105. The operation characteristic of the low-frequency signal compressor unit 103 is such that, for example, as shown in FIG. 3, the output level is kept low when the input level exceeds a threshold value. It should be noted here that the threshold determination of the input level is not performed using the low frequency signal S103. The advantage of performing the threshold determination using the input signal power information S102 is that the sound signal output from the small-diameter speaker even if the power of the input sound signal S101 is sufficiently small and the low frequency signal S103 is not compressed. Is not unnecessarily compressed, the low frequency signal S103 is not compressed.

  Next, the synthesizing unit 104 synthesizes the compressed low-frequency signal S105 and the mid-high frequency signal S104 to obtain a synthesized acoustic signal S106. Then, the synthesized signal power calculation unit 105 calculates the power of the synthesized acoustic signal S106 to obtain synthesized signal power information S107.

  Next, the synthesized signal compressor unit 106 compresses the dynamic range of the synthesized signal S106 using the synthesized signal power information S107 to obtain a compressed synthesized signal S108. The operational characteristics of the combined signal compressor unit 106 are the same as the operational characteristics of the low-frequency signal compressor unit 103 shown in FIG. Note that the compression ratio of the output level when the threshold value and the combined signal power information S107 exceed the threshold value can be set independently. Then, the amplifier unit 107 amplifies the compression synthesized signal S108 to obtain an output acoustic signal S109.

  Note that the internal state of the low-frequency signal compressor unit 103 can be changed depending on the magnitude of the input signal power information S102. For example, various parameters of the compression process are changed such that the threshold value in FIG. 3 is set to a high level when the input signal power information S102 is small and to a low level when the input signal power information S102 is large. When such control is performed, when the input acoustic signal S101 is small, the low frequency signal S103 is not compressed so much, and conversely, when the input acoustic signal S101 is large, it is compressed at a high ratio.

  According to the acoustic signal processing apparatus of the first embodiment as described above, by controlling the power of the low frequency signal according to the power of the input signal, a natural low frequency is included when the input signal is small. A sound signal of sound can be obtained, and when the input signal is large, the low range is compressed, and an acoustic signal with less sense of distortion is obtained even when reproduced by a small-diameter speaker. Also, by combining the low-frequency signal and the high-frequency signal with adjusted gain, a synthesized signal that minimizes the influence of the low-frequency signal that does not contribute much to the volume feeling can be obtained. Later, the dynamic range is further compressed. Then, after amplification, it is possible to increase the sound pressure when a music signal is sounded by a small-diameter speaker.

  FIG. 4 is a block diagram showing a configuration of an acoustic signal processing apparatus according to the second embodiment of the present invention. The acoustic signal processing apparatus 400 of the second embodiment includes an input signal power calculation unit 101 that calculates the power of an input acoustic signal, a filter unit 102 that separates the input acoustic signal into a low-frequency signal and a mid-high frequency signal, and a low-frequency signal A low-frequency signal gain control unit 401 that multiplies the signal by a gain, a gain table unit 402 that stores a table of gain information, a synthesis unit 104 that synthesizes the low-frequency signal and the high-frequency signal, and a synthesis that calculates the power of the synthesized signal The signal power calculation unit 105, a combined signal compressor unit 106 that compresses the dynamic range of the combined signal, and an amplifier unit 107 that amplifies the combined signal with the compressed dynamic range. The filter unit 102 includes an LPF unit 108 and an HPF unit 109. In the second embodiment, a low-frequency signal gain control unit 401 is provided as an example of a gain adjusting unit.

  In the case of the second embodiment, instead of compressing the dynamic range of the low frequency signal S103, the low frequency signal S103 is multiplied by a gain, and the low frequency is cut when the power of the input acoustic signal S101 is large. In the acoustic signal processing apparatus of the first embodiment shown in FIG. 1, a low-frequency signal gain control unit 401 is disposed instead of the low-frequency signal compressor unit 103, and gain related to the gain multiplied by the low-frequency signal S103. A gain table unit 402 storing an information table is added. In the gain table unit 402, gain information indicating gains set in advance corresponding to the respective powers of the input acoustic signal is stored as a table. Other components are the same as those of the acoustic signal processing apparatus of the first embodiment.

  The operation of the acoustic signal processing apparatus according to the second embodiment configured as described above will be described with reference to FIG. Here, the processing method of the low-frequency signal S103 will be mainly described.

  The low frequency signal gain control unit 401 uses the input signal power information S102 to obtain gain information S401 from the gain table unit 402, and multiplies the low frequency signal S103 by the gain to generate a compressed low frequency signal S105. As shown in FIG. 5, the characteristic of the gain information S401 is 1 in the sense that the gain is not changed when the input signal power information S102 is lower than the first threshold, and when the input signal power information S102 is lower than the first threshold and lower than the second threshold. Is a characteristic that decreases in the direction of decreasing from 1 to 0, and is 0 in the sense that the sound is silenced if it is greater than or equal to the second threshold. In the case of this processing, when the input acoustic signal S101 is sufficiently large, the compressed low frequency signal S105 becomes silent and the low frequency is lost, but it is possible to more reliably cut the low frequency that causes distortion during reproduction. It becomes. The operations of the other blocks are the same as those in the first embodiment described above.

  According to the acoustic signal processing device of the second embodiment as described above, by controlling the power of the low-frequency signal according to the power of the input signal, a natural low-frequency signal is included when the input signal is small. A sound signal of sound can be obtained. When the input signal is large, the low frequency range is compressed. Especially when the input signal is sufficiently large, the low frequency range is completely cut to reduce distortion even when played back on a small-diameter speaker. An acoustic signal is obtained. Also, by combining the low-frequency signal and the high-frequency signal with adjusted gain, a synthesized signal that minimizes the influence of the low-frequency signal that does not contribute much to the volume feeling can be obtained. Later, the dynamic range is further compressed. Then, after amplification, it is possible to increase the sound pressure when a music signal is sounded by a small-diameter speaker.

  FIG. 6 is a block diagram showing the configuration of an acoustic signal processing apparatus according to the third embodiment of the present invention. The acoustic signal processing apparatus 600 according to the third embodiment includes an input signal power calculation unit 101 that calculates the power of an input acoustic signal, a filter unit 102 that separates the input acoustic signal into a low-frequency signal and a mid-high frequency signal, The dynamic range is compressed by a low-frequency signal compressor unit 103 that compresses the dynamic range of the signal, a synthesis unit 104 that synthesizes the low-frequency signal and the high-frequency signal, a synthesized signal compressor unit 106 that compresses the dynamic range of the synthesized signal. And an amplifier unit 107 that amplifies the combined signal. The filter unit 102 includes an LPF unit 108 and an HPF unit 109.

  In the third embodiment, the composite signal power calculation unit 105 in the first embodiment is omitted, and the composite signal power information S107 necessary for the processing of the composite signal compressor unit 106 is replaced with the input signal power information S102. It is. Other configurations and operations of the respective blocks are the same as those of the acoustic signal processing apparatus of the first embodiment. In the third embodiment, since the combined signal power calculation unit 105 can be omitted, the processing load can be reduced.

  According to the acoustic signal processing device of the third embodiment, it is possible to realize the same effect as that of the first embodiment with a smaller processing load.

  FIG. 7 is a block diagram showing a configuration of an acoustic signal processing apparatus according to the fourth embodiment of the present invention. In the fourth embodiment, a volume adjustment unit (corresponding to an example of a volume adjustment unit) 701 is provided outside the acoustic signal processing device 700, and the acoustic signal processing device 700 includes a parameter storage unit (an example of a compression rate changing unit). (Corresponding) 702. The volume adjustment unit 701 is for the user to adjust the volume output from the on-board device on which the acoustic signal processing device 700 is mounted. The parameter storage unit 702 stores threshold values that the low-frequency signal compressor unit 103 and the synthesized signal compressor unit 106 refer to when operating, and sets parameters for adjusting the compression rate according to the volume information set by the volume adjustment unit 701. It is determined and output. The other components are the same as those in the first embodiment, and are omitted.

  The operation of the acoustic signal processing apparatus according to the fourth embodiment configured as described above will be described with reference to FIGS.

  Since the normal operation is the same as that of the first embodiment, the description thereof is omitted. When the user of the device operates the volume adjustment unit 701 to change the volume reproduced from the device on which the acoustic signal processing device 700 is mounted, the volume adjustment unit 701 transmits the volume information S701 to the parameter storage unit 702. The parameter storage unit 702 holds a table in which threshold values corresponding to individual values of the volume information S701 are recorded as shown in FIG. 10, and an appropriate threshold value corresponding to the volume information S701 is set to a low-frequency signal compressor. To the unit 103 and the combined signal compressor unit 106, respectively.

  Here, an operation when the user changes the volume setting shown in FIG. 10 from 4 to 3 is shown. FIG. 10 shows an example in which the device volume setting has seven levels from 0 to 6, the minimum volume is 0, and the maximum volume is 6. First, the user of the device operates the volume adjustment unit 701 to change the volume from 4 to 3. The volume adjustment unit 701 transmits volume information S701, which is information indicating that the volume is 3, to the parameter storage unit 702.

  The parameter storage unit 702 reads the threshold value for the low-frequency signal compressor unit 103 and the threshold value for the synthesized signal compressor unit 106 when the volume setting value is 3, from the table data recorded therein. According to FIG. 10, when the volume setting value is 3, the threshold for the low-frequency signal compressor unit 103 is “−6 [dB]” and the threshold for the synthesized signal compressor unit 106 is “−3 [dB]”. Is transmitted as low-frequency signal compressor threshold signal S702, and information that the threshold is "-3 [dB]" is transmitted as combined signal compressor threshold signal S703.

  The low-frequency signal compressor unit 103 applies the received low-frequency signal compressor threshold signal S702 as a new threshold to the processing. In the case of this example, the operating characteristics of the low-frequency signal compressor unit 103 change as shown in FIGS. Similarly, the synthesized signal compressor unit 106 applies the received synthesized signal compressor threshold signal S703 as a new threshold to the process. Subsequent operations are the same as those in the first embodiment, and a description thereof will be omitted. In this description, the case where the threshold value of the compressor is changed has been described, but other parameters for changing the compression rate may be used.

  According to the acoustic signal processing device of the fourth embodiment, it is possible to change the operation characteristics such as the compression ratio of the dynamic range described in the first embodiment in conjunction with the volume setting of the mounted device. It is. As a result, for example, when the volume setting is small, there is less possibility of distortion, so the compression rate can be lowered, and when the set volume is large, the compression rate can be set higher. In addition to the operations described in the embodiments, it is possible to perform an appropriate processing operation according to the volume setting status of the device.

  As described above, according to this embodiment, when the level of the input sound signal is sufficiently low, the low frequency range is not cut, and when the level of the input sound signal is large, the reproduced sound from the speaker does not have a sense of distortion. Thus, it is possible to provide an acoustic signal processing apparatus that can increase the sense of volume. For this reason, even when the acoustic signal processing device of this embodiment is applied to a small device such as a music reproducing device capable of reproducing music, an information terminal, or a mobile phone, and a small-diameter speaker is used as the sound output means. In addition, the sound pressure can be appropriately increased during the reproduction of the music signal, and the audible sound quality can be improved.

  The present invention can increase the sense of volume even when reproduced by a small-diameter speaker or the like without unnecessarily cutting the bass or increasing the sense of distortion of the reproduced sound, thereby improving the sound quality on hearing. Therefore, the present invention is useful for an acoustic signal processing apparatus or the like used for a device that sounds an acoustic signal with a small-diameter speaker such as a mobile phone.

The block diagram which shows the structure of the acoustic signal processing apparatus which concerns on the 1st Embodiment of this invention. The figure which shows the characteristic of the low-pass filter and high-pass filter in 1st Embodiment The figure which shows the operating characteristic of the low-pass signal compressor part in 1st Embodiment. The block diagram which shows the structure of the acoustic signal processing apparatus which concerns on the 2nd Embodiment of this invention. The figure which shows the characteristic of the gain which multiplies with respect to a low frequency signal in the low frequency signal gain control part in 2nd Embodiment. The block diagram which shows the structure of the acoustic signal processing apparatus which concerns on the 3rd Embodiment of this invention. The block diagram which shows the structure of the acoustic signal processing apparatus which concerns on the 4th Embodiment of this invention. The figure which shows the operating characteristic of the low-pass signal compressor part before the volume setting change in 4th Embodiment The figure which shows the operating characteristic of the low-pass signal compressor part after the volume setting change in 4th Embodiment The figure which shows the example of the table data which the parameter storage part in 4th Embodiment stores The block diagram which shows the structural example of the conventional acoustic signal processing apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Acoustic signal processing apparatus 101 Input signal power calculation part 102 Filter part 103 Low frequency signal compressor part 104 Synthesis | combination part 105 Synthetic signal power calculation part 106 Synthetic signal compressor part 107 Amplifier part 108 LPF part 109 HPF part 400 Acoustic signal processing apparatus 401 Low Region signal gain control unit 402 Gain table unit 600 Acoustic signal processing device 700 Acoustic signal processing device 701 Volume adjustment unit 702 Parameter storage unit S101 Input acoustic signal S102 Input signal power information S103 Low frequency signal S104 Middle high frequency signal S105 Compressed low frequency signal S106 Synthesized acoustic signal S107 Synthesized signal power information S108 Compressed synthesized signal S109 Output acoustic signal S401 Gain information S701 Volume information S702 Low frequency signal compressor threshold signal S703 Suppressor threshold signal

Claims (8)

An acoustic signal processing device that performs predetermined gain control on an acoustic signal,
Input signal power measuring means for measuring the power of the input acoustic signal;
Filtering means for separating the input acoustic signal into a low-frequency signal and a mid-high frequency signal in a predetermined frequency band;
Gain adjusting means for multiplying the low-frequency signal by an appropriate gain based on the power of the input acoustic signal measured by the input signal power measuring means;
Combining means for combining the low-frequency signal with the gain adjusted and the mid-high frequency signal;
Synthetic signal power measuring means for measuring the power of the synthesized acoustic signal;
Compression means for compressing the dynamic range of the synthesized acoustic signal based on the power of the synthesized acoustic signal measured by the synthesized signal power measuring means;
An acoustic signal processing apparatus comprising: amplifying means for multiplying the compressed synthesized acoustic signal by a gain. An acoustic signal processing device that performs predetermined gain control on an acoustic signal,
Input signal power measuring means for measuring the power of the input acoustic signal;
Filtering means for separating the input acoustic signal into a low-frequency signal and a mid-high frequency signal in a predetermined frequency band;
Gain adjusting means for multiplying the low-frequency signal by an appropriate gain based on the power of the input acoustic signal measured by the input signal power measuring means;
Combining means for combining the low-frequency signal with the gain adjusted and the mid-high frequency signal;
Compression means for compressing the dynamic range of the synthesized acoustic signal based on the power of the input acoustic signal measured by the input signal power measuring means;
An acoustic signal processing apparatus comprising: amplifying means for multiplying the compressed synthesized acoustic signal by a gain. The acoustic signal processing device according to claim 1 or 2,
The acoustic signal processing device, wherein the gain adjusting means includes low-frequency compression means for compressing a dynamic range of the low-frequency signal. The acoustic signal processing device according to claim 3,
The compression means is an acoustic signal processing apparatus capable of changing various parameters of compression processing with reference to power of the input acoustic signal. The acoustic signal processing device according to claim 1 or 2,
The acoustic signal processing device, wherein the gain adjusting means multiplies a value corresponding to the power of the input acoustic signal as a gain by using preset gain information. The acoustic signal processing device according to claim 5,
The gain information is 1 when the power of the input sound signal is smaller than the first threshold, decreases when the power exceeds the first threshold, and becomes 0 when the power exceeds the second threshold. An acoustic signal processing device. The acoustic signal processing device according to claim 1 or 2,
The input acoustic signal is a low-frequency signal in accordance with the characteristics of the mounted device including at least one of the diameter of the speaker connected to the output side of the acoustic signal processing device or the shape of the casing on which the acoustic signal processing device is mounted. Signal processing apparatus capable of changing the crossover frequency when separating into a high-frequency signal and a mid-high frequency signal. The acoustic signal processing device according to claim 1 or 2,
Compression rate changing means for receiving volume information relating to a set volume from a volume adjustment means of a mounted device on which the acoustic signal processing device is mounted, and determining a parameter for adjusting the compression ratio of the dynamic range in the compression means based on the volume information An acoustic signal processing device that changes the compression rate in conjunction with a volume adjustment function of the mounted device.

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