JPWO2008090896A1 - Sound adjustment method - Google Patents

Abstract

Provided is an acoustic adjustment method capable of easily adjusting sound quality according to listener's preference and various uses. The acoustic adjustment method of the present invention is an acoustic adjustment method in which a predetermined adjustment is performed on an audio signal and then input to an audio output device. In the adjustment, the phase frequency characteristic of the audio signal is independent of the amplitude frequency characteristic. To change.

Description

  The present invention relates to an acoustic adjustment method for adjusting a phase frequency characteristic of an audio signal.

  Conventionally, some acoustic devices use an FIR (finite impulse response) filter in order to equalize the amplitude frequency characteristic and phase frequency characteristic of the entire system so as to become a flat linear shape. The phase frequency characteristic is generally referred to as a phase characteristic or the like, and refers to a characteristic expressed by indicating the frequency on the horizontal axis and the phase on the vertical axis. The amplitude frequency characteristic is generally referred to as a frequency characteristic in the audio industry, and refers to a characteristic represented by indicating the frequency on the horizontal axis and the amplitude on the vertical axis.

  For example, Patent Document 1 describes a configuration in which an FIR filter is used and coefficients of the FIR filter are set so that the phase frequency characteristic of the sound output from a speaker has linearity.

On the other hand, Patent Document 2 has a configuration in which at least three stages of 180-degree phase shift circuits configured using operational amplifiers are connected in cascade, and the phase of the audio input signal corresponds to a logarithmic increase in frequency in the audible frequency range. A sound quality improvement circuit having a phase frequency characteristic for generating a phase delay in the range of 450 to 600 degrees in the range of audible frequencies by gradually delaying the sound is shown.
JP 2000-91865 A JP 2005-143093 A

  In the technique disclosed in Patent Document 1, the phase frequency characteristic of the sound output from the speaker is set to have linearity. Further, the technique of Patent Document 2 is configured to delay the phase with a linear gradient in response to a logarithmic increase in frequency. In this way, these prior art, since whether to what phase frequency characteristics in advance is defined, it is difficult to adjust the sound quality according to such the listener's preferences and various applications.

  The present invention has been made to solve the above-described problems, and it is an object of the present invention to provide an acoustic adjustment method capable of easily adjusting the sound quality according to the listener's preference and various uses. Yes.

  In order to achieve the above object, an acoustic adjustment method of the present invention is an acoustic adjustment method in which a predetermined adjustment is performed on an audio signal and then input to an acoustic output device. In the adjustment, the phase frequency characteristic of the audio signal is adjusted. Is changed independently of the amplitude frequency characteristic.

  According to this method, by adjusting the phase frequency characteristics independently of the amplitude frequency characteristics, it is possible to adjust the sound quality that could not be realized in the past. For example, by adjusting the phase in a certain band without changing the amplitude, the sound in the band whose phase has been advanced becomes more emphasized and can no longer be heard. As a result, the sound quality can be easily adjusted according to the listener's preference and various uses.

  In executing the acoustic adjustment method, the phase frequency characteristic of the audio signal may be changed in an arbitrary frequency range in the adjustment.

  In executing the acoustic adjustment method, the phase frequency characteristic of the audio signal may be changed based on an arbitrary phase frequency characteristic in the adjustment.

  In executing the acoustic adjustment method, the amplitude frequency characteristic of the audio signal may be changed independently of the phase frequency characteristic in the adjustment.

  In executing the acoustic adjustment method, only the phase frequency characteristic may be changed without changing the amplitude frequency characteristic of the audio signal in the adjustment.

  Further, when executing the above-described acoustic adjustment method, the audio signal is based on the phase frequency characteristic that is the same as the desired phase frequency characteristic by combining the phase frequency characteristic of the acoustic output device in the adjustment. The phase frequency characteristics may be changed. According to this method, the desired phase frequency characteristic can be simulated by the acoustic output device.

  Further, when executing the above-described acoustic adjustment method, the acoustic output device has a speaker, and in the adjustment, the phase frequency characteristic of the other specific speaker is the same by integrating with the phase frequency characteristic of the speaker. Based on such phase frequency characteristics, the phase frequency characteristics of the audio signal may be changed. According to this method, the phase frequency characteristic of the other specific speaker can be simulated by the speaker.

  Further, when executing the above-described acoustic adjustment method, the adjustment may be performed by digital signal processing.

  In executing the acoustic adjustment method, a filter device capable of setting its own phase frequency characteristic independently of the amplitude frequency characteristic is prepared, the audio signal is input to the filter device, and the filter By performing the adjustment by an apparatus, the phase frequency characteristic of the audio signal may be changed independently of the amplitude frequency characteristic.

  Further, in executing the acoustic adjustment method, the filter device is configured to be able to set the phase frequency characteristic independently of the amplitude frequency characteristic in an arbitrary frequency range. You may make it change the phase frequency characteristic of this audio | voice signal in arbitrary frequency ranges.

  In executing the acoustic adjustment method, the filter device is configured to be able to set an arbitrary phase frequency characteristic as the phase frequency characteristic, and in the adjustment, the phase frequency characteristic of the audio signal is changed. You may make it change based on this arbitrary phase frequency characteristics.

  In executing the acoustic adjustment method, the filter device is configured so that the amplitude frequency characteristic can be set independently of the phase frequency characteristic. In the adjustment, the amplitude frequency characteristic of the audio signal is set. The characteristics may be changed independently of the phase frequency characteristics.

  Further, when executing the acoustic adjustment method, the filter device is configured to change only the phase frequency characteristic without changing the amplitude frequency characteristic. Only the phase frequency characteristic may be changed without changing the amplitude frequency characteristic.

  In executing the acoustic adjustment method, the phase frequency characteristic of the filter device is set so that the total phase frequency characteristic of the filter device and the acoustic output device is the same as the desired phase frequency characteristic. You may make it do. According to this method, the desired phase frequency characteristic can be simulated by the acoustic output device.

  In executing the above-described acoustic adjustment method, the sound output device has a speaker, and the overall phase frequency characteristic of the filter device and the speaker is the same as the phase frequency characteristic of other specific speakers. As described above, the phase frequency characteristics of the filter device may be set. According to this method, the phase frequency characteristic of the other specific speaker can be simulated by the speaker.

Further, when executing the above-described acoustic adjustment method, the adjustment by the filter device may be performed by digital signal processing.

The filter device may include a finite impulse response filter, and the adjustment may be performed by changing a filter coefficient of the finite impulse response filter.

The arbitrary phase frequency characteristic may be specified by designating one or more sets of the center frequency, the frequency bandwidth, and the angle.

  The designation may be performed by inputting respective numerical values of the center frequency, the frequency bandwidth, and the angle.

  In addition, the designation is performed by operating the controls corresponding to the center frequency, the frequency bandwidth, and the angle, which are controls on the phase frequency characteristic curve displayed on the screen of the display device. You may do it.

  Further, the designation may be performed based on a center frequency, a frequency bandwidth, and an angle created in advance as data.

  The arbitrary phase frequency characteristic may be specified by drawing a desired phase frequency characteristic curve on the screen of the display device.

  The arbitrary phase frequency characteristic may be specified by manipulating a phase frequency characteristic curve displayed in advance on the screen of the display device.

  The arbitrary phase frequency characteristic may be specified by selecting one from a plurality of phase frequency characteristics prepared in advance.

  In the adjustment, the amplitude frequency characteristic of the audio signal may be changed based on an arbitrary amplitude frequency characteristic.

  Further, the arbitrary amplitude frequency characteristic may be specified by specifying one or more sets of the center frequency, the frequency bandwidth, and the gain.

  The designation may be performed by inputting respective numerical values of the center frequency, the frequency bandwidth, and the gain.

  The designation is performed by operating the operators corresponding to the center frequency, the frequency bandwidth, and the gain, which are operators on the amplitude frequency characteristic curve displayed on the screen of the display device. You may do it.

  The designation may be performed based on a center frequency, a frequency bandwidth, and a gain that are created in advance as data.

  Further, the arbitrary amplitude frequency characteristic may be specified by drawing a desired amplitude frequency characteristic curve on the screen of the display device.

  Further, the arbitrary amplitude frequency characteristic may be specified by manipulating an amplitude frequency characteristic curve displayed in advance on the screen of the display device.

  Further, the arbitrary amplitude frequency characteristic may be specified by selecting one from a plurality of amplitude frequency characteristics prepared in advance.

  The present invention has the configuration described above, and has an effect that it is possible to provide an acoustic adjustment method capable of easily adjusting the sound quality according to the listener's preference and various uses.

  The above object, other objects, features, and advantages of the present invention will become apparent from the following detailed description of the preferred embodiments with reference to the accompanying drawings.

FIG. 1 is a block diagram illustrating an example of a configuration of an acoustic device using an acoustic adjustment device that executes an acoustic adjustment method according to an embodiment of the present invention. FIG. 2 is a circuit diagram showing an example of the configuration of the FIR filter in the embodiment of the present invention. FIG. 3 is a diagram showing a display screen of the operation input unit of the first configuration example according to the embodiment of the present invention. FIG. 4 is a diagram showing a display screen of the operation input unit of the second configuration example according to the embodiment of the present invention. FIG. 5 is a diagram showing a display screen of the operation input unit of the sixth configuration example according to the embodiment of the present invention. FIG. 6 is a diagram showing a display screen of the operation input unit of the seventh configuration example according to the embodiment of the present invention. FIG. 7 is a diagram showing a display screen of the operation input unit of the eighth configuration example according to the embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Acoustic adjustment apparatus 2 D / A converter 3 Amplifier 4 Speaker 11 FIR filter 12 Operation control part 13 Operation input part

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a block diagram illustrating an example of a configuration of an acoustic device using an acoustic adjustment device that executes an acoustic adjustment method according to an embodiment of the present invention.

  This acoustic device includes an acoustic adjustment device 1 that is a filter device, a D / A (digital / analog) converter 2 connected to the acoustic adjustment device 1, and a D / A converter 2 subsequent to the acoustic adjustment device 1. And an acoustic output device connected via the cable.

  The sound output device includes an amplifier 3 connected to the D / A converter 2 and a speaker 4 connected to the amplifier 3.

  The acoustic adjustment device 1 includes an FIR (finite impulse response) filter 11, an arithmetic control unit 12 that functions as a filter coefficient setting unit, and an operation input unit 13 that functions as a change characteristic designation unit. The FIR filter 11 of the acoustic adjustment device 1 is inserted in the middle of a signal line connecting the external input terminal IN of the acoustic device and the D / A converter 2.

  The FIR filter 11 performs digital signal processing. For example, a digital audio signal obtained by A / D converting an analog audio signal output from a microphone, or a digital audio signal output from a recording medium playback device such as a CD player, It is input via the external input terminal IN of the audio device. A signal that has been subjected to predetermined processing (filtering) by the FIR filter 11 is input to the D / A converter 2 to be converted into an analog signal, further amplified by the amplifier 3 and output to the speaker 4. Is output as a loud sound (acoustic signal).

  FIG. 2 is a circuit diagram showing an example of the configuration of the FIR filter 11.

The FIR filter 11 includes n delay circuits 21 connected in cascade, (n + 1) multipliers 22, and an adder 23. Each delay circuit 21 outputs each input signal after being delayed by a sampling period, and each multiplier 22 multiplies the input signal by a filter coefficient h _k (k = 0 to n) set corresponding to each input signal. The outputs of the multipliers 22 are added by the adder 23 and output. In such an FIR filter 11, an amplitude frequency characteristic (hereinafter referred to as “amplitude characteristic”) and a phase frequency characteristic (hereinafter referred to as “phase characteristic”) are determined by setting a filter coefficient h _k .

  Here, the phase characteristic refers to a characteristic expressed with the frequency on the horizontal axis and the phase on the vertical axis. The amplitude characteristic refers to a characteristic represented with a frequency as a horizontal axis and an amplitude (for example, gain) as a vertical axis.

The arithmetic control unit 12 is constituted by, for example, a microcomputer, derives a filter coefficient h _k corresponding to the operation of the operation input unit 13 and sets it in the FIR filter 11. Each filter coefficient h _k is set as a gain of each multiplier 22. In the case of first to third configuration examples to be described later, the arithmetic control unit 12 calculates a filter coefficient h _k corresponding to the amplitude characteristic and the phase characteristic specified by the operation of the operation input unit 13 and supplies the filter coefficient h _k to the FIR filter 11. Set. In this case, the filter coefficient h _k can be _obtained by performing inverse fast Fourier transform (inverse FFT) or the like on the information of the frequency characteristics (amplitude characteristics and phase characteristics).

  In the operation input unit 13, for example, an operation for designating an amplitude characteristic and a phase characteristic set in the FIR filter 11 is performed by the operator. In the case of first to third configuration examples described later, the operation input unit 13 is configured using, for example, a liquid crystal pen tablet that integrates a liquid crystal display and a pen tablet. In this case, a display screen for inputting amplitude characteristics and phase characteristics is displayed, and a stylus pen is used as a pointing device.

  Hereinafter, although each structural example is described, in each structural example, the structure of the operation input part 13 and the calculation control part 12 differs, and it is the same about another structure.

(First configuration example)
FIG. 3 is a diagram illustrating a display screen of the operation input unit 13 of the first configuration example.

  In the case of the display screen 31 shown in FIG. 3, the lower left area of the screen is an amplitude characteristic designation area for designating the amplitude characteristic, and the amplitude characteristic designated by the left upper area is displayed as an amplitude characteristic curve 34. This is an amplitude characteristic display area. The lower right area of the screen is a phase characteristic designation area for designating phase characteristics, and the upper right area is a phase characteristic display area for displaying the phase characteristics designated by the phase characteristic curve 35.

  In the amplitude characteristic designation area, for example, a gain adjustment operator 32 for setting a gain (gain) at each of a plurality of preset frequencies within a range of audible frequencies (20 Hz to 20 kHz) is displayed. Similarly, in the phase characteristic designation area, a phase adjustment operator 33 for setting the phase at each of a plurality of preset frequencies within the above audible frequency range is displayed. For example, when the above-described plurality of preset frequencies are 10, the gain adjusting operator 32 and the phase adjusting operator 33 arranged from left to right in FIG. For example, it corresponds to the frequencies of 31 Hz, 62 Hz, 125 Hz, 250 Hz, 500 Hz, 1 kHz, 2 kHz, 4 kHz, 8 kHz, and 16 kHz. Moreover, although the numerical value of these frequencies is displayed on the display screen 31, the illustration is abbreviate | omitted in FIG.

  Using the stylus pen, the operator moves (drags) the position of each gain adjustment operator 32 up and down so as to obtain a desired amplitude characteristic, and sets the gain at each frequency. Similarly, the phase at each frequency is set by moving the position of each phase adjustment operator 33 up and down so as to obtain the desired phase characteristics. Then, an amplitude characteristic curve 34 corresponding to the position of each gain adjustment operator 32 is displayed, and a phase characteristic curve 35 corresponding to the position of each phase adjustment operator 33 is displayed. Each gain adjusting operator 32 and each phase adjusting operator 33 are displayed as an initial state in which the gain or phase at each frequency is set to 0, for example, as an initial state where setting has never been performed. The

In the operation input unit 13 on which the above-described display screen 31 shown in FIG. 3 is displayed, for example, by touching a “confirm” button (not shown) on the display screen 31 with a stylus pen, The display information indicating the position of 32 and the display information indicating the position of each phase adjustment operator 33 are output to the arithmetic control unit 12. As a result, the amplitude characteristic and phase characteristic to be set in the FIR filter 11 are designated by the operation input unit 13. The arithmetic control unit 12 converts the display information of each gain adjustment operator 32 into amplitude characteristic information and converts the display information of each phase adjustment operator 33 into phase characteristic information, then the amplitude characteristic information and phase Based on the characteristic information, a filter coefficient h _k is obtained by performing an inverse FFT or the like, and is set in the FIR filter 11. The display information of each gain adjustment operator 32 is information about a wide interval frequency (for example, 31 Hz, 62 Hz,..., 8 kHz, 16 kHz as described above). Amplitude characteristic information is obtained by interpolating amplitude information (gain) regarding the frequency of the gap between these frequencies. Similarly, the display information of each phase adjustment operator 33 is also information on a wide interval frequency (for example, 31 Hz, 62 Hz,..., 8 kHz, 16 kHz as described above). Then, the phase characteristic information is obtained by interpolating the phase information regarding the frequency between these frequencies.

When the gain or phase is set once and then the setting is changed next, before the change, each gain adjusting operation element 32 and each phase adjusting operation element 33 are in the state when they are set immediately before. The state before the change is displayed. From this state, the operating elements 32 and 33 are moved up and down to change the setting. At this time, in addition to the amplitude characteristic curve 34 and the phase characteristic curve 35 displayed corresponding to the positions of the operation elements 32 and 33, the amplitude characteristic curve 34a and the phase characteristic curve 35a before the change are displayed. Also good. This facilitates comparison between the amplitude characteristic and phase characteristic before the change and the amplitude characteristic and phase characteristic to be newly set.

Each gain adjusting operator 32 and each phase adjusting operator 33 are not displayed on the screen as described above, but are configured by hardware that is actually operated by an operator by hand. May be.

  Note that the amplitude characteristic information is data of a numerical string representing the amplitude characteristic as shown in the graph of the amplitude characteristic curve 34, for example, and the phase characteristic information is the phase as shown in the graph of the phase characteristic curve 35, for example. It is data of a numerical sequence representing the characteristics.

(Second and third configuration examples)
FIG. 4 is a diagram illustrating a display screen of the operation input unit 13 of the second configuration example.

  In the case of the display screen 41 shown in FIG. 4, the upper area of the upper half is an area for specifying the amplitude characteristic (amplitude characteristic display area), and the lower area of the lower half is for specifying the phase characteristic. This is an area (phase characteristic display area).

  In the upper amplitude characteristic display area, for example, a line (amplitude characteristic line) 42 for displaying the amplitude characteristic set in the range of the audible frequency is displayed. The line 42 is in a state where the gain is set to 0 in the entire range of the audible frequency as an initial state, for example. Alternatively, it may be set to a state other than this. The operator uses the stylus pen to drag an arbitrary portion of the line 42 to form the line 42 showing a desired amplitude characteristic.

  In the lower phase characteristic display area, for example, a line (phase characteristic line) 43 for displaying the phase characteristic set within the range of the audible frequency is displayed. The line 43 is in a state where the phase is set to 0 in the entire range of the audible frequency as an initial state, for example. Alternatively, it may be set to a state other than this. The operator uses the stylus pen to drag an arbitrary portion of the line 43 to form the line 43 showing a desired phase characteristic.

In the operation input unit 13 of the second configuration example described above, the arbitrary lines 42 and 43 are deformed to form the lines 42 and 43 indicating the desired characteristics. For example, the display screen 41 in the initial state is used. In FIG. 4, a screen other than the lines 42 and 43 is displayed and only the lines 42 and 43 are not displayed, and the operator draws the lines 42 and 43 indicating desired characteristics using a stylus pen. (This may be referred to as the operation input unit 13 of the third configuration example).

In the operation input unit 13 of the second and third configuration examples in which the display screen 41 shown in FIG. 4 described above is displayed, for example, a “confirm” button (not shown) on the display screen 41 is touched with a stylus pen. Thus, the display information of the line 42 and the display information of the line 43 are output to the arithmetic control unit 12. As a result, the amplitude characteristic and phase characteristic to be set in the FIR filter 11 are designated by the operation input unit 13. The arithmetic control unit 12 converts the display information of the line 42 into amplitude characteristic information and converts the display information of the line 43 into phase characteristic information. Then, based on the amplitude characteristic information and the phase characteristic information, an inverse FFT or the like is performed. A filter coefficient h _k is obtained by performing an operation, and is set in the FIR filter 11.

  When the operation input unit 13 of the first, second, and third configuration examples configured to display the display screen as shown in FIGS. 3 and 4 is used, the operator can display the display screen on the display screen. Thus, the desired amplitude characteristic and phase characteristic of the FIR filter 11 can be easily specified.

(Fourth configuration example)
Next, a fourth configuration example will be described. In the fourth configuration example, the arithmetic control unit 12 includes a storage unit including, for example, an internal memory of a microcomputer that constitutes the arithmetic control unit 12, and a plurality of amplitude characteristic information and a plurality of pieces of information regarding the FIR filter 11 are included therein. Are stored (stored) in advance. Then, by operating the operation input unit 13, desired amplitude characteristic information and phase characteristic information are selected from those stored in the storage unit. The operation input unit 13 in the case of the fourth configuration example is provided with, for example, an amplitude characteristic designation button corresponding to each of a plurality of amplitude characteristics and a phase characteristic designation button corresponding to each of the plurality of phase characteristics. These designation buttons may be a push button type that is actually selected and operated by a human hand, or may be displayed on the touch panel and selected by touching with a finger or a stylus pen. In either case, the operation for specifying the amplitude characteristic and the phase characteristic is easy. The operation input unit 13 outputs an amplitude characteristic selection signal corresponding to the selected amplitude characteristic designation button and a phase characteristic selection signal corresponding to the selected phase characteristic designation button to the arithmetic control unit 12. The arithmetic control unit 12 reads out the amplitude characteristic information and the phase characteristic information corresponding to each selection signal from the storage unit, and performs a computation such as inverse FFT based on the amplitude characteristic information and the phase characteristic information. The coefficient h _k is obtained and set in the FIR filter 11.

  In the fourth configuration example, the operation input unit 13 may be configured so that information stored in the storage unit in the arithmetic control unit 12 can be rewritten. For example, when the storage unit of the arithmetic control unit 12 stores the amplitude characteristic information and the phase characteristic information of the FIR filter 11 corresponding to the acoustic output apparatus configured by the amplifier 3 and the speaker 4, the acoustic output apparatus May be rewritten to the phase characteristic information and the amplitude characteristic information of the FIR filter 11 corresponding to the other acoustic output device. In this case, the operation input unit 13 is provided with reading means for reading information on a recording medium such as a flash memory and a CD, and new amplitude characteristic information and phase characteristic information read from the recording medium are stored (stored) in the storage unit. What is necessary is just to comprise. The recording medium may be distributed from an acoustic adjustment device or an acoustic device manufacturer, or a host computer such as an acoustic adjustment device or an acoustic device manufacturer by a user operating a personal computer (personal computer). Then, a new amplitude characteristic information and phase characteristic information file may be downloaded and recorded on a recording medium.

(Fifth configuration example)
Next, a fifth configuration example will be described. In the fifth configuration example, for example, the operation input unit 13 is provided with the gain at each of a plurality of preset frequencies from the initial state of the FIR filter 11 (for example, the gain is 0) or the amplitude characteristic set immediately before. An amplitude increase frequency designation button for increasing and an amplitude decrease frequency designation button for decreasing the gain are provided corresponding to each frequency, and the FIR filter 11 is set in the initial state (for example, the phase is 0) or immediately before. A phase advance frequency designation button for advancing the phase at each of a plurality of preset frequencies and a phase delay frequency designation button for delaying the phase are provided corresponding to each frequency. . When the above-mentioned plurality of preset frequencies are ten, ten amplitude increase frequency designation buttons, amplitude decrease frequency designation buttons, phase advance frequency designation buttons, and phase delay frequency designation buttons are provided. Each designation button corresponds to, for example, ones having frequencies of 31 Hz, 62 Hz, 125 Hz, 250 Hz, 500 Hz, 1 kHz, 2 kHz, 4 kHz, 8 kHz, and 16 kHz. These designation buttons may be actually selected by a human hand, such as a push button type, or may be displayed on the touch panel and selected by touching with a finger or a stylus pen. .

  In this case, when a certain amplitude increase frequency designation button is selected and operated n times, the operation input unit 13 outputs a selection signal corresponding to the selected amplitude increase frequency designation button to the arithmetic control unit 12 n times. When the decrease frequency designation button is selected n times, a selection signal corresponding to the selected amplitude decrease frequency designation button is output to the arithmetic control unit 12 n times. When a certain phase advance frequency designation button is selected n times, a selection signal corresponding to the selected phase advance frequency designation button is output n times to the arithmetic control unit 12, and a certain phase delay frequency designation button is output. When n is selected n times, a selection signal corresponding to the selected phase delay frequency designation button is output to the arithmetic control unit 12 n times.

  The arithmetic control unit 12 increases the gain of the frequency corresponding to the amplitude increase frequency designation button for which the selection signal is output n times by a predetermined value × n with respect to the amplitude characteristic of the FIR filter 11 set immediately before. In addition, information for determining the changed amplitude characteristic is obtained by decreasing the gain of the frequency corresponding to the amplitude reduction frequency designation button for which the selection signal is output n times by a predetermined value × n, and the amplitude characteristic is based on the information. Ask for information. The predetermined value is a predetermined value. The information for determining the changed amplitude characteristics obtained by the selection signal of each amplitude increase frequency designation button and amplitude decrease frequency designation button is a frequency with a wide interval (for example, 31 Hz, 62 Hz,..., 8 kHz, 16 kHz as described above. ), The arithmetic control unit 12 interpolates amplitude information (gain) relating to the frequency gap between these frequencies to obtain amplitude characteristic information.

  In addition, the arithmetic control unit 12 sets the phase of the frequency corresponding to the phase advance frequency designation button for which the selection signal is output n times to a predetermined angle × n with respect to the phase characteristic of the FIR filter 11 set immediately before. In addition to determining the phase characteristic after the change by delaying the phase of the frequency corresponding to the phase delay frequency designation button for which the selection signal is output n times by a predetermined angle × n, Obtain phase characteristic information. The predetermined angle is a predetermined value. Information for determining the phase characteristics after change obtained by the selection signal of each phase advance frequency designation button and phase slow frequency designation button is a frequency with a wide interval (for example, 31 Hz, 62 Hz,..., 8 kHz as described above) , 16 kHz), the arithmetic control unit 12 interpolates the phase information related to the gap frequency between these frequencies to obtain the phase characteristic information.

Further, the arithmetic control unit 12 obtains a filter coefficient h _k by performing an inverse FFT or the like based on the amplitude characteristic information and the phase characteristic information obtained as described above, and sets it in the FIR filter 11. .

When the operation input unit 13 of the fifth configuration example is used, the amplitude characteristic of the FIR filter 11 is changed by a simple operation such as pressing an amplitude increase frequency designation button and an amplitude decrease frequency designation button corresponding to the frequency whose amplitude is to be changed. can do. Further, the phase characteristics of the FIR filter 11 can be changed by a simple operation such as pressing a phase advance frequency designation button and a phase delay frequency designation button corresponding to the frequency whose phase is to be changed.

(Sixth configuration example)

FIG. 5 is a diagram illustrating a display screen of the operation input unit 13 of the sixth configuration example.

  Here, the operation input part 13 is comprised using the liquid crystal display which has the display screen 101, a keyboard, a mouse | mouth, etc., for example.

  In the case of the display screen 101 shown in FIG. 5, an amplitude characteristic display area for displaying the amplitude characteristic curve 102 or the like is arranged in the left area of the screen, and the phase characteristic for displaying the phase characteristic curve 103 or the like in the right area of the screen. A display area is arranged.

  Below the amplitude characteristic display area, respective operation buttons 104a, 104b for designating a set point number (No.), a center frequency (f), a frequency bandwidth (Q), and a gain (G) at the center frequency, 105a, 105b, 106a, 106b, 107a, and 107b and boxes 104, 105, 106, and 107 in which designated values are displayed are displayed. Similarly, below the phase characteristic display area, each operation button 108a for designating a set point number (No.), a center frequency (f), a frequency bandwidth (Q), and an angle (D) at the center frequency. , 108b, 109a, 109b, 110a, 110b, 111a, 111b and boxes 108, 109, 110, 111 in which designated values are displayed.

  The operator sets the center frequency, the frequency bandwidth, and the gain at the center frequency for each set point number (for example, 1, 2, 3,...) So as to obtain a desired amplitude characteristic. The operator can increase and decrease the set point number displayed in the box 104 by clicking the increase button 104a and the decrease button 104b using a mouse, for example. The center frequency displayed in the box 105 can be increased and decreased by clicking the increase button 105a and the decrease button 105b. Further, by clicking the increase button 106a and the decrease button 106b, the frequency bandwidth displayed in the box 106 can be increased or decreased. Further, the gain displayed in the box 107 can be increased and decreased by clicking the increase button 107a and the decrease button 107b.

The operation input unit 13 outputs the amplitude setting information including the center frequency, the frequency bandwidth, and the gain for each set point number set by the above operation to the calculation control unit 12. The arithmetic control unit 12 obtains amplitude characteristic information based on each amplitude setting information. Display information for displaying the amplitude characteristic curve 102 is created based on the amplitude characteristic information, and the amplitude characteristic curve 102 is displayed on the display screen 101 of the operation input unit 13.

Further, the operator sets the center frequency, the frequency bandwidth, and the angle at the center frequency for each set point number (for example, 1, 2, 3,...) So as to obtain a desired phase characteristic. The operator can increase and decrease the set point number displayed in the box 108 by clicking the increase button 108a and the decrease button 108b using, for example, a mouse. The center frequency displayed in the box 109 can be increased and decreased by clicking the increase button 109a and the decrease button 109b. Further, by clicking the increase button 110a and the decrease button 110b, the frequency bandwidth displayed in the box 110 can be increased and decreased. Further, by clicking the increase button 111a and the decrease button 111b, the angle displayed in the box 111 can be increased and decreased.

The operation input unit 13 outputs the phase setting information including the center frequency, the frequency bandwidth, and the angle for each setting point number set by the above operation to the calculation control unit 12. The arithmetic control unit 12 obtains phase characteristic information based on each phase setting information. Display information for displaying the phase characteristic curve 103 is created based on the phase characteristic information, and the phase characteristic curve 103 is displayed on the display screen 101 of the operation input unit 13.

Further, the arithmetic control unit 12 obtains a filter coefficient h _k by performing an inverse FFT or the like based on the obtained amplitude characteristic information and phase characteristic information, and sets it in the FIR filter 11.

Further, during the operation for changing the setting, the amplitude characteristic curve 102a and the phase characteristic curve 103a before the change may be displayed. This facilitates comparison between the amplitude characteristic and phase characteristic before the change and the amplitude characteristic and phase characteristic to be newly set.

Further, during the operation for changing the setting, the target amplitude characteristic curve is displayed in the amplitude characteristic display area of the display screen 101, and the target phase characteristic curve is displayed in the phase characteristic display area. Also good. This makes it easy to create the amplitude characteristic curve and the phase characteristic curve so as to overlap the target amplitude characteristic curve and the target phase characteristic curve.

Operation buttons (104a, 104b), (105a, 105b), (106a, 106b), (107a, 107b) for setting amplitude characteristics, and operation buttons (108a, 108b) for setting phase characteristics , (109a, 109b), (110a, 110b), (111a, 111b), for example, a slide bar or the like as shown by the operation elements 32, 33 in FIG. 3 may be used. Further, these operation buttons, slide bars, and other controls are not displayed on the screen as described above, and may be configured by hardware that is actually operated by the operator's hands. .

(Seventh configuration example)

FIG. 6 is a diagram illustrating a display screen of the operation input unit 13 of the seventh configuration example.

In the case of the display screen 131 shown in FIG. 6, this is an amplitude characteristic drawing area for creating an amplitude characteristic curve indicating the amplitude characteristic specified by the upper area, and a phase characteristic curve indicating the phase characteristic specified by the lower area. This is a phase characteristic drawing area for creating

  The operation input unit 13 is configured using, for example, a liquid crystal display having a display screen 131, a keyboard, a mouse, and the like.

  When an operation start command is given by the operation input unit 13, a mountain-shaped amplitude characteristic curve 141 having a predetermined shape and size is displayed at a predetermined frequency position on the frequency axis in the amplitude characteristic drawing area of the display screen 131. At the same time, a mountain-shaped phase characteristic curve 151 having a predetermined shape and size is also displayed in the phase characteristic drawing area.

  The amplitude characteristic curve 141 has two operators 142 and 143. The operation element 142 is provided at the peak position in the center of the amplitude characteristic curve 141, and the operation element 143 is provided in the middle of the amplitude characteristic curve 141. The operator 142 can move (drag) the cursor in the vertical and horizontal directions of the screen by moving the cursor to the operator 142 with the mouse. In addition, the operator 143 can move (drag) the cursor in the horizontal direction of the screen by using the mouse to align the cursor with the operator 143.

  The peak gain of the amplitude characteristic curve 141 can be adjusted by moving the operation element 142 in the vertical direction. For example, when the operator 142 of the amplitude characteristic curve 141 is dragged upward, it expands to a similar state as shown by the amplitude characteristic curve 141a, for example, and when the mouse button is released, that is, when it is dropped, the enlargement is performed at that position. Stop. Further, when the operation element 142 is dragged downward, although not shown, the amplitude characteristic curve 141 is reduced in a similar shape.

  Further, the frequency (center frequency) that becomes the gain of the peak of the amplitude characteristic curve 141 can be changed by moving the operation element 142 in the left-right direction. For example, when the operator 142 of the enlarged amplitude characteristic curve 141a is dragged to the right, the amplitude characteristic curve 141a moves in the horizontal direction as indicated by, for example, the amplitude characteristic curve 141b, and the movement stops at the point where it is dropped.

  The frequency bandwidth of the amplitude characteristic curve 141 can be changed by moving the operator 143 in the left-right direction. For example, when the operator 143 of the amplitude characteristic curve 141b whose maximum gain and its frequency are moved is dragged horizontally toward the right direction, the slope of the amplitude characteristic curve becomes gentle as shown as the amplitude characteristic curve 141c. That is, the frequency bandwidth is increased. When the operator 143 is dragged leftward, the slope of the amplitude characteristic curve 141 becomes steep. That is, the frequency bandwidth is reduced. Such a change in inclination continues until dropping.

  By creating the amplitude characteristic curve by the operation as described above, the amplitude setting information including the center frequency, the frequency bandwidth, and the gain at one set point is determined. Further, by repeating the above-described operation a plurality of times, for example, an amplitude characteristic curve in an audible frequency range is created (drawn), and a center frequency, a frequency bandwidth, and a center frequency at each of a plurality of setting points corresponding thereto are drawn. Amplitude setting information including the gain at is determined.

  The phase characteristic curve 151 also has two operators 152 and 153. The operation element 152 is provided at the peak position in the center of the phase characteristic curve 151, and the operation element 153 is provided in the middle of the phase characteristic curve 151. The operator 152 can move (drag) the cursor in the vertical and horizontal directions of the screen by moving the cursor to the operator 152 with the mouse. In addition, the operator 153 can move (drag) the cursor in the horizontal direction of the screen by using the mouse to align the cursor with the operator 153.

  The peak angle (phase) of the phase characteristic curve 151 can be adjusted by moving the operation element 152 in the vertical direction. For example, if the operator 152 of the phase characteristic curve 151 is dragged upward, it expands to a similar state as shown by the phase characteristic curve 151a, for example, and if it is dropped, the expansion is stopped at that position. Further, when the operator 152 is dragged downward, the phase characteristic curve 151 is reduced in a similar state, although not shown.

  Further, the frequency (center frequency) that becomes the angle of the peak of the phase characteristic curve 151 can be changed by moving the operation element 152 in the left-right direction. For example, when the operator 152 of the enlarged phase characteristic curve 151a is dragged in the right direction, the phase characteristic curve 151a moves in the horizontal direction, for example, as indicated by the phase characteristic curve 151b, and the movement stops at the point where it is dropped.

The frequency bandwidth of the phase characteristic curve 151 can be changed by moving the operator 153 in the left-right direction. For example, when the operator 153 of the phase characteristic curve 151b whose maximum angle and its frequency have been moved is dragged horizontally toward the right direction, the slope of the phase characteristic curve becomes gentle as shown by the phase characteristic curve 151c. That is, the frequency bandwidth is increased. Further, when the operator 153 is dragged to the left, the slope of the phase characteristic curve 151 becomes steep. That is, the frequency bandwidth is reduced. Such a change in inclination continues until dropping.

By creating the phase characteristic curve by the operation as described above, phase setting information including the center frequency, the frequency bandwidth, and the gain at one setting point is determined. In addition, by repeating the above-described operation a plurality of times, for example, a phase characteristic curve in an audible frequency range is created (drawn), and the center frequency, frequency bandwidth, and center frequency at each of a plurality of setting points corresponding thereto are drawn. Phase setting information consisting of an angle at is determined.

The operation input unit 13 outputs the amplitude setting information at each setting point and the phase setting information at each setting point set by the above operation to the calculation control unit 12. The arithmetic control unit 12 obtains amplitude characteristic information based on each amplitude setting information and obtains phase characteristic information based on each phase setting information. Based on the obtained amplitude characteristic information and phase characteristic information, an arithmetic operation such as inverse FFT is performed. To obtain a filter coefficient h _k and set it in the FIR filter 11.

In addition, during the operation for changing the setting, the amplitude characteristic curve before the change is displayed in the amplitude characteristic drawing area of the display screen 131, and the phase characteristic curve before the change is displayed in the phase characteristic drawing area. Also good. This facilitates comparison between the amplitude characteristic and phase characteristic before the change and the amplitude characteristic and phase characteristic to be newly set.

  Further, during the operation for changing the setting, the target amplitude characteristic curve is displayed in the amplitude characteristic drawing area of the display screen 131, and the target phase characteristic curve is displayed in the phase characteristic drawing area. Also good. This makes it easy to create the amplitude characteristic curve and the phase characteristic curve so as to overlap the target amplitude characteristic curve and the target phase characteristic curve. In this case, information for displaying the target amplitude characteristic curve and the target phase characteristic curve is stored in the storage unit of the arithmetic control unit 12, for example.

(Eighth configuration example)

FIG. 7 is a diagram illustrating a display screen of the operation input unit 13 of the eighth configuration example.

Here, the operation input part 13 is comprised using the liquid crystal display which has the display screen 161, a keyboard, a mouse | mouth, etc., for example.

  In the case of the display screen 161 shown in FIG. 7, a tabular amplitude characteristic setting file and a phase characteristic setting file are displayed. The set point numbers (No.) of both of these files are displayed in advance in the order of 1, 2, 3,.

  The operator operates a keyboard or the like, for example, and inputs desired values in the center frequency (f), frequency bandwidth (Q), and gain (G) at the center frequency of the amplitude characteristic setting file. Similarly, a desired value is entered in the center frequency (f), frequency bandwidth (Q), and angle (D) at the center frequency field of the phase characteristic setting file.

In the operation input unit 13, for each setting point number input to the amplitude characteristic setting file, each amplitude setting information including the center frequency, frequency bandwidth and gain, and each setting point number input to the phase characteristic setting file The phase setting information including the center frequency, the frequency bandwidth, and the angle is output to the arithmetic control unit 12. The arithmetic control unit 12 obtains amplitude characteristic information based on each amplitude setting information and obtains phase characteristic information based on each phase setting information. Further, the arithmetic control unit 12 obtains a filter coefficient h _k by performing an inverse FFT or the like based on the obtained amplitude characteristic information and phase characteristic information, and sets it in the FIR filter 11.

In the eighth configuration example, the amplitude characteristic setting file and the phase characteristic setting file are created by the operation input unit 13, but the amplitude characteristic setting file and the phase characteristic are obtained using a personal computer other than the acoustic adjustment device. If a setting file is created and uploaded to the acoustic adjustment device, it is not necessary to provide a display for displaying the display screen 161 on the operation input unit 13 of the acoustic adjustment device, and the acoustic adjustment device has a simple configuration. Can be downsized.

Further, in a personal computer or setting device other than the acoustic adjustment device, the display screen as shown in FIGS. 5 and 6 described above can be displayed, and amplitude setting information set in the same manner as in the sixth and seventh configuration examples and The phase setting information may be filed to create an amplitude characteristic setting file and a phase characteristic setting file, which may be uploaded to the acoustic adjustment device.

Further, the storage unit of the arithmetic control unit 12 stores information on a plurality of amplitude characteristic setting files corresponding to a plurality of amplitude characteristics (a plurality of amplitude characteristic specifying information) and a plurality of phase characteristic setting files corresponding to the plurality of phase characteristics. Information (a plurality of phase characteristic specifying information) is stored in advance, and the operation input unit 13 is used to select desired amplitude characteristic specifying information and phase from those stored in the storage unit as in the above-described fourth configuration example. You may comprise so that characteristic specific information may be selected. In this case, the arithmetic control unit 12 reads the amplitude characteristic specifying information and the phase characteristic specifying information from the storage unit according to the operation of the operation input unit 13, and includes the read amplitude characteristic specifying information (consisting of one or a plurality of amplitude setting information). Amplitude characteristic information based on the information), phase characteristic information based on the phase characteristic identification information (information including one or a plurality of phase setting information), and further based on the amplitude characteristic information and the phase characteristic information. A filter coefficient h _k is obtained and set in the FIR filter 11.

As described above, in any case of the first to eighth configuration examples, for example, a button or a menu for flattening the phase characteristics may be provided in the set frequency range. This facilitates setting of flat phase characteristics (for example, the angle is 0 in the entire frequency range to be set). Similarly, in the frequency range to be set, for example, buttons and menus for flattening the amplitude characteristics may be provided. This facilitates the setting of flat amplitude characteristics (amplitude is constant in the set frequency range).

  In the present embodiment, the FIR filter 11 that can individually set the amplitude characteristic and the phase characteristic by setting the filter coefficient is used, and the amplitude characteristic and the phase characteristic of the FIR filter 11 are individually set. Therefore, it is possible to easily adjust the sound quality output from the speaker 4 according to the listener's preference and various uses. In particular, it is possible to adjust the sound quality output from the speaker 4 by delaying or advancing the phase of a certain frequency.

  As described above, in the present embodiment, the FIR filter 11 is used for acoustic adjustment. That is, digital signal processing technology is used.

  Since the phase characteristics of the FIR filter 11 can be set by using the operation input unit 13 as described above, various acoustics that could not be realized by the conventional acoustic adjustment methods. Adjustment is possible. Since the FIR filter 11 is used as described above, an arbitrary phase characteristic can be set. That is, an arbitrary phase characteristic can be given for each frequency. Moreover, it is possible to adjust the phase characteristics only in an arbitrary frequency range. For example, it is possible to change the phase of the input audio signal only in the frequency range from 100 Hz to 200 Hz and not to change the phase in other frequency ranges.

  Further, since the phase characteristic and the amplitude characteristic of the FIR filter 11 can be set using the operation input unit 13 as described above, the phase characteristic and the amplitude characteristic are set independently. Can do. That is, it is possible to change only the phase characteristic from the already set characteristic (phase characteristic) to another characteristic (phase characteristic) without changing the amplitude characteristic already set in the FIR filter 11.

  On the contrary, only the amplitude characteristic is changed from the already set characteristic (amplitude characteristic) to another characteristic (amplitude characteristic) without changing the phase characteristic already set in the FIR filter 11. You can also.

  Furthermore, both the phase characteristic and amplitude characteristic already set in the FIR filter 11 can be changed to different characteristics.

  Also, an amplitude characteristic that gives a constant gain regardless of the frequency is set for the FIR filter 11, and the phase characteristic of the FIR filter 11 is set so as to change only the phase characteristic of the audio signal. It is also possible to change the phase characteristics set in the FIR filter 11 in various ways.

  In particular, by advancing the phase without changing the amplitude, it becomes possible to make adjustments that could not be realized in the past, such as making the sound of the band with the advanced phase more audible and noisy. . Furthermore, since the phase characteristics can be changed in combination with the change of the amplitude characteristics, effective settings can be made for each of them, and more complicated and free acoustic adjustment can be performed.

  In addition, when it is desired to apply a certain desired phase characteristic to the input audio signal, the following may be performed. That is, the phase characteristic of the FIR filter 11 may be set so that the total phase characteristic of the sound output device including the amplifier 3 and the speaker 4 and the FIR filter 11 is the same as the desired phase characteristic. It is. More specifically, the difference between the phase characteristic of the sound output device composed of the amplifier 3 and the speaker 4 and the desired phase characteristic may be set as the phase characteristic of the FIR filter 11. For the input audio signal, the amplitude characteristic may not be changed, but only the phase characteristic may be changed. In addition, if desired phase characteristics are desired and at the same time desired amplitude characteristics are applied to the input audio signal, the amplitude characteristics of the sound output device including the amplifier 3 and the speaker 4 and the desired A difference from the amplitude characteristic may be set as the amplitude characteristic of the FIR filter 11.

For example, in the first configuration example to the third configuration example and the sixth to eighth configuration examples described above, the phase characteristic and the amplitude characteristic of the FIR filter 11 are designated by the operation input unit 13, but the amplifier 3 and the speaker 4 are designated. The total phase characteristic and amplitude characteristic of the sound output device constituted by the FIR filter 11 may be designated. In this case, the phase characteristic information and the amplitude characteristic information of the sound output device are stored in the storage unit of the arithmetic control unit 12. Then, the arithmetic control unit 12 obtains a difference between the information indicating the phase characteristic specified by the operation input unit 13 and the phase characteristic information of the sound output device, and uses the difference as the phase characteristic information of the FIR filter 11 on the display screen. The difference between the information representing the specified amplitude characteristic and the amplitude characteristic information of the sound output device is obtained and used as the amplitude characteristic information of the FIR filter 11. Further, the arithmetic control unit 12 obtains a filter coefficient h _k by performing an inverse FFT or the like based on the amplitude characteristic information and the phase characteristic information of the FIR filter 11 obtained as described above, and obtains the filter coefficient h _k by using the FIR filter. 11 is set.

  In this case, the phase characteristic information and the amplitude characteristic information of the sound output device stored in the storage unit of the arithmetic control unit 12 are obtained by measuring the characteristics of the sound output device constituted by the amplifier 3 and the speaker 4 by a known measuring means. This is information obtained by measurement. The arithmetic control unit 12 can rewrite the information stored in the storage unit, and when the sound output device is changed to another sound output device, the phase characteristic information and the amplitude characteristic information of the other sound output device. Can be stored in the storage unit. In this case, for example, the operation input unit 13 is provided with a reading unit that reads information on a recording medium such as a flash memory or a CD, and stores amplitude characteristic information and phase characteristic information of another acoustic output device read from the recording medium. What is necessary is just to comprise so that it may store in a part (memory | storage). The recording medium may be distributed from an acoustic adjustment device or an acoustic device manufacturer, or a host computer such as an acoustic adjustment device or an acoustic device manufacturer by a user operating a personal computer (personal computer). Then, a new amplitude characteristic information and phase characteristic information file may be downloaded and recorded on a recording medium.

In the fourth configuration example described above, the plurality of phase characteristic designation buttons and the plurality of amplitude characteristic designation buttons of the operation input unit 13 are used for designating (selecting) the phase characteristics and amplitude characteristics of the FIR filter 11. However, it may be configured to be used for designating (selecting) the overall phase characteristics and amplitude characteristics of the sound output device and the FIR filter 11. In this case, in the storage unit of the arithmetic control unit 12, the total phase characteristic information and amplitude characteristic information of the acoustic output device and the FIR filter 11 designated by the plurality of phase characteristic designation buttons and the plurality of amplitude characteristic designation buttons, and the acoustic The phase characteristic information and the amplitude characteristic information of the output device are stored. Then, the arithmetic control unit 12 obtains a difference between the phase characteristic information designated by the phase characteristic designation button and the phase characteristic information of the sound output device, and uses the difference as the phase characteristic information of the FIR filter 11 and designated by the amplitude characteristic designation button. The difference between the amplitude characteristic information thus obtained and the amplitude characteristic information of the sound output device is obtained and used as the amplitude characteristic information of the FIR filter 11. Further, the arithmetic control unit 12 obtains a filter coefficient h _k by performing an inverse FFT or the like based on the amplitude characteristic information and the phase characteristic information of the FIR filter 11 obtained as described above, and obtains the filter coefficient h _k by using the FIR filter. 11 is set.

  In this case, the phase characteristic information and the amplitude characteristic information of the sound output device stored in the storage unit of the arithmetic control unit 12 are obtained by measuring the characteristics of the sound output device constituted by the amplifier 3 and the speaker 4 by a known measuring means. This is information obtained by measurement. The arithmetic control unit 12 can rewrite the information stored in the storage unit, and when the sound output device is changed to another sound output device, the phase characteristic information and the amplitude characteristic information of the other sound output device. Can be stored in the storage unit. In addition, information on the overall phase characteristics and amplitude characteristics of the sound output device and the FIR filter 11 specified by the phase characteristics designation button and the amplitude characteristics designation button can be rewritten. In this way, the configuration for rewriting the information in the storage unit is similar to the case described above, and the operation input unit 13 is provided with reading means for reading information on a recording medium such as a flash memory and a CD, and the information is read from the recording medium. What is necessary is just to comprise so that new information may be stored (memory | storage) in a memory | storage part.

Here, the information on the total phase characteristics and amplitude characteristics of the acoustic output device and the FIR filter 11 stored in the storage unit of the arithmetic control unit 12 is the phase characteristics and amplitudes according to various uses in which the acoustic device is used. This is characteristic information. As such information, for example, when a speech is performed using an acoustic device, that is, the audio signal from the microphone is input to the input terminal IN after being A / D converted, and the microphone is used. When giving a speech, there is phase characteristic information and amplitude characteristic information suitable for letting the listener hear the speech of the speaker clearly. When an emergency broadcast is performed using an acoustic device, that is, a digital audio signal output from a recording medium playback device such as a CD player is input to the input terminal IN, and an emergency announcement is made. When broadcast, there is phase characteristic information and amplitude characteristic information suitable for the listener, such as easy listening to the contents of the emergency announcement. In addition, when music (BGM) is played using an audio device, that is, a digital audio signal output from a recording medium playback device such as a CD player is input to the input terminal IN, and music is broadcast. In such a case, there are phase characteristic information and amplitude characteristic information suitable for the broadcast so that the broadcast is not harsh.

The information stored in the storage unit of the arithmetic control unit 12 is classified by sound source such as “information for speech”, “information for music (pops)”, and “information for music (rock)”. The information may be stored and selected as information, or as information classified according to use, such as “information for store BGM”, “information for listening to music”, and “information for street speech”. It may be stored and selected, or may be stored and selected as information classified by image such as “clearly” and “softly”.

  Further, the phase characteristics of a specific speaker other than the speaker 4 can be simulated using the acoustic adjustment device 1. For that purpose, the phase characteristic of the acoustic adjustment device 1 may be set so that the total phase characteristic of the speaker 4 and the acoustic adjustment device 1 is the same as the phase characteristic of the other specific speaker.

  In other words, if the phase characteristics of other specific speakers and the phase characteristics of the existing speaker 4 are known, the difference between the phase characteristics of those speakers is set as the phase characteristic of the FIR filter 11, so that 4 can imitate the phase characteristics of other specific speakers. Here, the amplitude characteristic is not necessarily set so that the difference between the amplitude characteristic of another specific speaker and the amplitude characteristic of the existing speaker 4 is equal to the amplitude characteristic of the FIR filter 11. By setting the difference between the phase characteristic of the speaker and the phase characteristic of the existing speaker 4 to be equal to the phase characteristic of the FIR filter 11, another specific speaker can be imitated to some extent by the existing speaker 4. .

  When the amplitude characteristics of other specific speakers and the amplitude characteristics of the existing speaker 4 are known, the difference between the amplitude characteristics of those speakers is set as the amplitude characteristic of the FIR filter 11 and the existing speakers are set. In step 4, not only the phase characteristics of other specific speakers but also the amplitude characteristics may be imitated together.

  The arithmetic control unit 12 has a storage unit as described above, and can store frequency characteristic information and the like of the speaker therein.

  The storage unit of the arithmetic control unit 12 stores phase characteristic information and amplitude characteristic information of the speaker 4. The phase characteristic information and the amplitude characteristic information are information obtained by measuring the characteristics of the speaker 4 with a known measuring means.

  Further, phase characteristic information and amplitude characteristic information of other specific speakers other than the speaker 4 are also stored in the storage unit of the arithmetic control unit 12. The phase characteristic information and the amplitude characteristic information are also information obtained by measuring the characteristics of the other specific speaker by a known measuring means.

  Thus, the arithmetic control unit 12 has all the information necessary for simulating the phase characteristics and amplitude characteristics of other specific speakers by the FIR filter 11 and the speakers 4. Then, the arithmetic control unit 12 calculates phase characteristic information and amplitude characteristic information to be set in the FIR filter 11 from these pieces of information, further calculates a filter coefficient, and sets it in the FIR filter 11, thereby setting an existing speaker. 4 can imitate other specific speakers. In this case, information necessary for simulating the phase characteristics and amplitude characteristics of other specific speakers is stored in the storage unit of the arithmetic control unit 12 in advance, so that the operation input unit 13 is not used. Even if the operation input unit 13 is not provided, the existing speaker 4 can imitate other specific speakers. Further, if a filter coefficient that can be calculated based on the phase characteristic information and amplitude characteristic information to be set in the FIR filter 11 is stored in advance in the storage unit of the calculation control unit 12, the calculation control unit 12 stores the filter coefficient. Is set in the FIR filter 11, and other specific speakers can be imitated by the existing speakers 4.

  As described above, the storage unit of the arithmetic control unit 12 can store information on speaker characteristics and information on desired characteristics (phase characteristics and amplitude characteristics) according to various uses of the acoustic device. it can. For example, when giving a speech using an acoustic device, it is important that the voice of the speaker is clearly heard by the listener. If phase characteristic information and amplitude characteristic information suitable for clearly listening to the voice of speech are stored in the storage unit of the arithmetic control unit 12, the phase characteristic and amplitude corresponding to the use (representation) of the acoustic device. The characteristics can be set in the FIR filter 11. For example, in the storage unit of the arithmetic control unit 12, phase characteristic information and amplitude characteristic information suitable for clearly speaking a voice, and phase characteristic information and amplitude characteristic of an acoustic output device including the amplifier 3 and the speaker 4 If the information is stored in advance, phase characteristics and amplitude characteristics suitable for clearly speaking the voice can be realized by the combined phase characteristics and amplitude characteristics of the FIR filter 11 and the sound output device. In addition, the arithmetic control unit 12 calculates phase characteristic information and amplitude characteristic information to be set in the FIR filter 11, calculates filter coefficients, and sets them in the FIR filter 11, so that the voice can be heard clearly. Phase characteristics and amplitude characteristics suitable for the above can be realized. In this case, the operation input unit 13 is stored in the storage unit of the arithmetic control unit 12 by storing in advance information necessary for realizing phase characteristics and amplitude characteristics suitable for clearly speaking the voice. Without using it, that is, even without the operation input unit 13, it is possible to realize phase characteristics and amplitude characteristics suitable for clearly speaking speech. Further, if a filter coefficient that can be calculated based on the phase characteristic information and amplitude characteristic information to be set in the FIR filter 11 is stored in advance in the storage unit of the calculation control unit 12, the calculation control unit 12 stores the filter coefficient. Is set in the FIR filter 11, phase characteristics and amplitude characteristics suitable for clearly speaking speech can be realized. Similarly, when performing emergency broadcasting using an audio device, or when playing music (BGM) using an audio device, the arithmetic control unit 12 outputs phase characteristic information and amplitude characteristic information suitable for each case. If it is stored in the storage section, it is possible to set the phase characteristic and the amplitude characteristic according to the use of the acoustic device in the FIR filter 11.

  In the above embodiment, the D / A converter 2 may be included in the acoustic adjustment device 1. When an analog audio signal is input to the input terminal IN, an A / D (analog / digital) converter may be inserted between the input terminal IN and the FIR filter 11. A device may be included in the acoustic adjustment device 1.

  Further, the acoustic adjustment device 1 may be configured to adjust only the phase characteristic without changing the amplitude characteristic of the audio signal input to and output from the FIR filter 11. In this case, the operation input unit 13 does not require a configuration for adjusting the amplitude characteristic of the FIR filter 11.

  From the foregoing description, many modifications and other embodiments of the present invention are obvious to one skilled in the art. Accordingly, the foregoing description should be construed as illustrative only and is provided for the purpose of teaching those skilled in the art the best mode of carrying out the invention. The details of the structure and / or function may be substantially changed without departing from the spirit of the invention.

  INDUSTRIAL APPLICABILITY The present invention is useful as an acoustic adjustment method for easily adjusting the sound quality according to the listener's preference and various uses.

Claims (32)

A sound adjustment method in which a predetermined adjustment is performed on an audio signal and then input to the sound output device,
An acoustic adjustment method in which, in the adjustment, the phase frequency characteristic of the audio signal is changed independently of the amplitude frequency characteristic.   The acoustic adjustment method according to claim 1, wherein in the adjustment, a phase frequency characteristic of the audio signal is changed in an arbitrary frequency range.   The acoustic adjustment method according to claim 1, wherein, in the adjustment, the phase frequency characteristic of the audio signal is changed based on an arbitrary phase frequency characteristic.   The acoustic adjustment method according to claim 1, wherein in the adjustment, the amplitude frequency characteristic of the audio signal is changed independently of the phase frequency characteristic.   The acoustic adjustment method according to claim 1, wherein, in the adjustment, only the phase frequency characteristic is changed without changing the amplitude frequency characteristic of the audio signal.   In the adjustment, the phase frequency characteristic of the audio signal is changed based on a phase frequency characteristic that is the same as a desired phase frequency characteristic by combining with the phase frequency characteristic of the sound output device. The acoustic adjustment method according to any one of 5. The sound output device has a speaker;
The phase frequency characteristic of the audio signal is changed based on a phase frequency characteristic that is the same as the phase frequency characteristic of another specific speaker by combining with the phase frequency characteristic of the speaker in the adjustment. The acoustic adjustment method according to any one of 1 to 5.   The acoustic adjustment method according to claim 1, wherein the adjustment is performed by digital signal processing. Prepare a filter device that can set its own phase frequency characteristics independent of amplitude frequency characteristics,
The acoustic adjustment according to claim 1, wherein the audio signal is input to the filter device and the adjustment is performed by the filter device, whereby the phase frequency characteristic of the audio signal is changed independently of the amplitude frequency characteristic. Method. The filter device is configured such that the phase frequency characteristic can be set independently of the amplitude frequency characteristic in an arbitrary frequency range,
The acoustic adjustment method according to claim 9, wherein in the adjustment, a phase frequency characteristic of the audio signal is changed in the arbitrary frequency range. The filter device is configured such that an arbitrary phase frequency characteristic can be set as the phase frequency characteristic,
The acoustic adjustment method according to claim 9 or 10, wherein, in the adjustment, the phase frequency characteristic of the audio signal is changed based on the arbitrary phase frequency characteristic. The filter device is configured such that the amplitude frequency characteristic can be set independently of the phase frequency characteristic,
The acoustic adjustment method according to claim 9, wherein in the adjustment, the amplitude frequency characteristic of the audio signal is changed independently of the phase frequency characteristic. The filter device is configured to change only the phase frequency characteristic without changing the amplitude frequency characteristic,
The acoustic adjustment method according to claim 9, wherein in the adjustment, only the phase frequency characteristic is changed without changing the amplitude frequency characteristic of the audio signal.   The phase frequency characteristic of the filter device is set so that a total phase frequency characteristic of the filter device and the acoustic output device is the same as a desired phase frequency characteristic. Acoustic adjustment method. The sound output device has a speaker;
The phase frequency characteristic of the filter device is set so that the total phase frequency characteristic of the filter device and the speaker is the same as the phase frequency characteristic of another specific speaker. The acoustic adjustment method described in 1. The acoustic adjustment method according to claim 9, wherein the adjustment by the filter device is performed by digital signal processing.
The acoustic adjustment method according to claim 9, wherein the filter device includes a finite impulse response filter, and the adjustment is performed by changing a filter coefficient of the finite impulse response filter.
The acoustic adjustment method according to claim 3, wherein the arbitrary phase frequency characteristic is specified by specifying one or more sets of a center frequency, a frequency bandwidth, and an angle.
  The acoustic adjustment method according to claim 18, wherein the designation is performed by inputting numerical values of a center frequency, a frequency bandwidth, and an angle. The designation is performed by operating the operators corresponding to the center frequency, the frequency bandwidth, and the angle, respectively, on the phase frequency characteristic curve displayed on the screen of the display device. Item 19. The acoustic adjustment method according to Item 18.

The acoustic adjustment method according to claim 18, wherein the designation is performed based on a center frequency, a frequency bandwidth, and an angle created in advance as data. The acoustic adjustment method according to claim 3, wherein the arbitrary phase frequency characteristic is specified by drawing a desired phase frequency characteristic curve on a screen of a display device.
  The acoustic adjustment method according to claim 3, wherein the arbitrary phase frequency characteristic is specified by operating a phase frequency characteristic curve displayed in advance on a screen of a display device. The acoustic adjustment method according to claim 3, wherein the arbitrary phase frequency characteristic is specified by selecting one of a plurality of phase frequency characteristics prepared in advance.
The acoustic adjustment method according to claim 1, wherein in the adjustment, the amplitude frequency characteristic of the audio signal is changed based on an arbitrary amplitude frequency characteristic.
  The acoustic adjustment method according to claim 25, wherein the arbitrary amplitude frequency characteristic is specified by specifying one or more sets of a center frequency, a frequency bandwidth, and a gain.   27. The acoustic adjustment method according to claim 26, wherein the designation is performed by inputting numerical values of a center frequency, a frequency bandwidth, and a gain.   The designation is performed by operating the controls corresponding to the center frequency, the frequency bandwidth, and the gain, which are controls on the amplitude frequency characteristic curve displayed on the screen of the display device. Item 27. The acoustic adjustment method according to Item 26.   27. The acoustic adjustment method according to claim 26, wherein the designation is performed based on a center frequency, a frequency bandwidth, and a gain created in advance as data.   The acoustic adjustment method according to claim 25, wherein the arbitrary amplitude frequency characteristic is specified by drawing a desired amplitude frequency characteristic curve on a screen of a display device.   The acoustic adjustment method according to claim 25, wherein the arbitrary amplitude frequency characteristic is specified by operating an amplitude frequency characteristic curve displayed in advance on a screen of a display device.   The acoustic adjustment method according to claim 25, wherein the arbitrary amplitude frequency characteristic is specified by selecting one of a plurality of amplitude frequency characteristics prepared in advance.

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