JP3988750B2 - Sound pressure frequency characteristic adjusting device, information communication system, and program - Google Patents

Description

  The present invention relates to a technique for adjusting a sound pressure frequency characteristic in a reproduction sound field.

Conventionally, an adjustment technique for correcting a sound signal so as to obtain a desired sound pressure frequency characteristic using a reference sound signal such as pink noise is known (see, for example, Patent Document 1). In this conventional adjustment technique, a reference sound signal emitted from a speaker is input by a microphone, and a sound pressure frequency characteristic obtained by dividing the input sound signal into a plurality of frequency bands becomes a desired characteristic. This is realized by correcting the sound pressure in each frequency band.
Japanese Patent Laid-Open No. 06-311587

  Here, a karaoke apparatus can be considered as one of the effective objects of adjusting the sound pressure frequency characteristic. The size of the room where the karaoke equipment is installed varies considerably. For example, even if it is a dedicated karaoke box (room), there are a variety of rooms such as a room for several people, a room for around 10 people, a party room for around 20 people, and a karaoke device installed in the reception hall. For example, the room will be 100 people, and the wideness will be considerable.

  However, the desired sound pressure frequency characteristic disclosed in Patent Document 1 is single. The object of adjustment of the sound pressure frequency characteristic disclosed in Patent Document 1 is a car audio device, and even if there is a difference in the size of the passenger compartment, there is no difference of many times. It is considered that no particular problem occurs even if the characteristics are single.

  On the other hand, in the case of a karaoke apparatus, as described above, the difference in the sound field in the installation environment is considerably large. If the target sound pressure frequency characteristic is single, for example, a party room of about 20 persons or a 100 person level based on the target sound pressure frequency characteristic that becomes a desired characteristic for a room of several persons described above, for example. In the karaoke apparatus installed in the room, the sound pressure frequency characteristic is adjusted. If the degree of breadth of the playback sound field increases, there will be an appropriate target sound pressure frequency characteristic corresponding to the degree of breadth, but if a single target sound pressure frequency characteristic is adopted, the appropriate sound pressure frequency characteristic will be It becomes impossible to approach the target sound pressure frequency characteristic.

  Accordingly, an object of the present invention is to realize an appropriate adjustment of sound pressure frequency characteristics according to the degree of width of a reproduction sound field.

  The sound pressure frequency characteristic adjusting device of the present invention made to solve the above-mentioned problems is a measurement sound signal generating means for generating a measurement sound signal (in the embodiment, the sound source unit 24: in this section, In order to facilitate understanding of the invention, the components described in the column “Best Mode for Carrying Out the Invention” are shown in parentheses as necessary, and this description is meant to limit the scope of the claims. And an equalizer capable of changing the sound pressure frequency characteristic of the measurement sound signal generated from the measurement sound signal generating means by changing the gain value (15-band equalizer 25 in the embodiment). And sound generation means (speaker 40 in the embodiment) for emitting the output from the equalizer as an audible sound, and sound input for inputting the audible sound emitted from the sound generation means and converting it into an electrical signal A stage (a microphone 50 in the embodiment), an analysis unit (a frequency analysis unit 27 in the embodiment) for analyzing a gain value for specifying a sound pressure frequency characteristic based on an electric signal from the sound input unit, and a wide and narrow sound field Determination gain value storage means for storing a plurality of determination sound pressure frequency characteristics set according to the degree (= determination gain value) (in the embodiment, the hard disk storage device 14 of the main control unit 10). ) And a gain value (= reproduction gain value) for specifying a sound pressure frequency characteristic in a reproduction sound field, which is an analysis result by the analysis unit, and a plurality of determination gain values stored in the determination gain value storage unit Thus, the width determination means (CPU 21 of the sound processing unit 20 in the embodiment) for determining the width of the reproduced sound field, and a plurality of target sound pressure frequency characteristics set according to the width of the sound field. Target gain value storage means (in the embodiment, the hard disk storage device 14 of the main control unit 10) for storing the gain to be specified (= target gain value), and the target gain value corresponding to the degree of wideness determined by the wideness determination means Is read from the target gain value storage means, and based on the read target gain value, an equalizer is set so that the sound pressure frequency characteristics in the reproduced sound field coincide with the target sound pressure frequency characteristics corresponding to the degree of wideness determined by the wideness determination means. Gain value adjusting means (in the embodiment, the CPU 11 of the main control unit 10 and the CPU 21 of the sound processing unit 20).

  According to the sound pressure frequency characteristic adjusting apparatus of the present invention having such a configuration, a plurality of determination gain values and target gain values set in accordance with the degree of narrowness of the sound field are stored. For example, there are three types of playback sound fields: large room (accommodation level of about 100 people), normal room (accommodation level of about 20 people), and small room (accommodation level of several people). Assume that the degree of width is set. It is conceivable to adopt a gain value actually measured in advance in each room of a wide size as a determination gain value. At this time, there are various ways of determining the determination gain value, such as employing an average value of a plurality of rooms. As for the target gain value, as in the case of the determination gain value, a gain value actually measured in advance in each room of a wide or narrow area may be used, but further adjustment may be performed. This is based on the fact that the adjustment of the sound pressure frequency characteristic may actually be corrected according to the adjustment target. For example, the measurement sound signal is a simple sound signal such as pink noise, but when a karaoke apparatus is assumed, the karaoke accompaniment sound is a fairly complicated sound signal. For this reason, for example, if there is a target sound pressure frequency characteristic that is considered more appropriate on the creator side of the karaoke music piece, it is also preferable to set a gain value suitable for it.

  The sound pressure frequency characteristic adjusting apparatus according to the present invention determines the degree of breadth of the reproduction sound field by comparing the reproduction gain value with a plurality of determination gain values. This determination can be made based on the determination gain value corresponding to the minimum difference absolute value among the absolute values of the differences between the reproduction gain value and the plurality of determination gain values. Thus, when the degree of width of the room increases, the analysis result of the sound pressure frequency characteristic for the same measurement sound signal differs. Therefore, if this is compared with an actually measured value in the reproduction sound field as a determination gain value, the degree of room width in the reproduction sound field can be easily determined.

  If the degree of room width can be determined in this way, the sound pressure frequency characteristic in the reproduction sound field matches the corresponding target sound pressure frequency characteristic based on the target gain value corresponding to the determined degree of breadth and width. It is only necessary to adjust the gain value of the equalizer. Since this target gain value is in accordance with the degree of breadth of the room, an appropriate adjustment of the sound pressure frequency characteristic in accordance with the degree of breadth of the reproduced sound field can be realized.

  The determination gain value is set according to the extent of the sound field. For example, it is set according to the extent of the sound field determined by the distance between the side wall of the room constituting the sound field and the sound input means. Can be considered. In general, the shape of the room is not constant, but for example, assuming a karaoke box, the shape of the room is often rectangular. Also, the installation location of karaoke equipment is usually not located in the center of the room, but often in the corner. The location where the microphone is installed, that is, the location where the singing is performed, is determined to some extent based on the location where the karaoke equipment is installed. Therefore, it can be considered that the distance from the installation location of the microphone to the side wall reflects the extent of the room. Therefore, the determination gain value is set according to the degree of sound field width determined by the distance between the side wall of the room and the sound input means (for example, a microphone). Although the degree of breadth and width may be determined based on the floor area of the room, it is also useful to pay attention to the position of the sound input means (for example, the microphone) described above, particularly assuming a karaoke application.

  In general, an equalizer is configured to be able to change a gain value for each frequency band divided into a plurality of frequency bands in order to change sound pressure frequency characteristics. For example, the one that can change the gain value for each of the 15 frequency bands is called a 15-band equalizer. When such an equalizer is used, the determination gain value and the target gain value may be similarly set for each of the frequency bands divided into a plurality.

  In addition, regarding the determination gain value and the target gain value, as described above, it has been described that it is preferable to use the actual measurement value as the determination gain value and further modify the actual measurement value to obtain the target gain value. In particular, they may be the same value. In this case, the gain value that is both the determination gain value and the target gain value need only be stored in the storage means that is also the determination gain value storage means and the target gain value storage means.

  An information communication system according to a fifth aspect includes a plurality of terminal devices including the sound pressure frequency characteristic adjusting device according to any one of the first to fourth aspects and a distribution host device, and the distribution host device and the terminal device Are configured to be able to communicate with each other via a communication line. The distribution host device includes a distribution control unit (CPU 101 of the distribution host device 100) that distributes the determination gain value and the target gain value to the terminal device. Based on the determination gain value distributed from the host device, the extent of the reproduction sound field is determined, and the gain value adjusting means of the terminal device is based on the target gain value distributed from the distribution host device. Adjust.

  When the determination gain value and the target gain value are distributed from the distribution host device in this way, for example, in an information communication system in which tens of thousands of terminal devices are connected to one distribution host device. If there is, a very remarkable effect is obtained. That is, for example, the gain value indicating the sound pressure frequency characteristic of the reproduction sound field is measured and calculated in each terminal device, and the gain value is uploaded to the distribution host device, and the target gain value corresponding to each terminal device on the distribution host device side Can be calculated or selected and downloaded to the terminal device again. However, in the case of a system in which tens of thousands of terminal devices are connected to one distribution host device as described above, the target gain value for each of the tens of thousands of terminal devices in the distribution host device Calculation or selection is required, and the processing load becomes very large. On the other hand, if the determination gain value and the target gain value are distributed from the distribution host device as described above, it is effective in reducing the processing load of the distribution host device if each terminal device can cope with it later. It is. For example, even if the type of the gain value for determination or the target gain value is increased or finely corrected, it can be handled by distributing from the distribution host device, which is very convenient.

  As a communication line between the distribution host device and the terminal device, a public switched network (PSTN) or the Internet can be used. When constructing such a communication system between a host and a terminal, a method called host call / terminal call is conceivable. In the present invention, a system for calling from either a host or a terminal is adopted. However, as long as the determination gain value and the target gain value can be distributed, the adjustment work is completed in the terminal device, and the adjustment work can be executed at an arbitrary timing on the terminal device side.

  The information communication system of the present invention can be applied to any system that requires adjustment of sound pressure frequency characteristics in the terminal device, but as the number of terminals increases as described above, the distribution host device This is advantageous in terms of reducing processing load and communication load. In that sense, it is a very effective invention for a so-called online karaoke system. In the case of the online karaoke system, the terminal device includes data storage means for storing music data and music playback means for playing back music based on the music data stored in the data storage means. With regard to this music data, for example, music data related to new music is often distributed regularly or irregularly from the distribution host device to the terminal device. Therefore, it is conceivable that the distribution control means of the distribution host device distributes the determination gain value and the target gain value when distributing music data to the terminal device.

  In addition, when the analysis means, the wide / decrease determination means, and the gain value adjustment means included in the sound pressure frequency characteristic adjustment device are realized by a computer, the sound pressure frequency characteristic adjustment device executes the computer as described in claim 8. It can also be understood as an invention as a program to do. Such a program is recorded on a computer-readable recording medium such as a flexible disk, a magneto-optical disk, a CD-ROM, a hard disk, a ROM, or a RAM, and is loaded into a computer for execution as necessary. These functions as each means can be realized by loading and executing the program.

  Embodiments to which the present invention is applied will be described below with reference to the drawings. The embodiments of the present invention are not limited to the following examples, and can take various forms as long as they belong to the technical scope of the present invention.

FIG. 1 is a block diagram showing a configuration of a communication karaoke system as an embodiment of an information communication system.
In the communication karaoke system of this embodiment, a communication karaoke terminal 1 as a terminal device and a distribution host device 100 are connected via a general public network (PSTN) or the Internet 90, and the communication karaoke system is connected to the communication karaoke terminal 100 from the distribution host device 100. Various types of information are distributed to the terminal 1. The communication karaoke terminal 1 and the distribution host device 100 may be connected via the Internet. Although only one communication karaoke terminal 1 is shown in FIG. 1, a large number (for example, a level such as tens of thousands) of communication karaoke terminals 1 are connected.

  The distribution host device 100 includes a CPU 101, a ROM 102, a RAM 103, a hard disk storage device (HDD) 104, a communication control unit 105, and the like that control the operation of the entire device. The hard disk storage device (HDD) 104 stores song data, a target gain value, a determination gain value, and the like for distribution to the communication karaoke terminal 1. The target gain value and the determination gain value will be described in detail later. The communication control unit 105 is connected to the communication karaoke terminal 1 via a general public line network or the Internet 90.

On the other hand, the communication karaoke terminal 1 is roughly provided with a main control unit 10 and a voice processing unit 20.
[Configuration of Main Control Unit 10]
In the main control unit 10, a modem 12, a RAM 13, a hard disk storage device (HDD) 14, an operation panel 15, and a video processing unit 16 are connected to a CPU 11 that controls the operation of the entire main control unit 10 via a bus.

The modem 12 is connected to the distribution host device 100 via a general public line network or the Internet 90.
The hard disk storage device 14 stores a system program, an application program, and the like for controlling the operation of the communication karaoke terminal 1, and when the communication karaoke terminal 1 is turned on and a startup program is executed, these programs are stored. Is read into the RAM 13. Alternatively, the disk storage device 14 includes an area for storing song data for performing a karaoke performance, an area for storing a target gain value and a determination gain value, in addition to an area for storing the above-described program. The target gain value and the determination gain value are distributed from the distribution host device 100 described above.

  The operation panel 15 is provided on the front surface of the communication karaoke terminal 1 and includes a song code input switch, a key change switch, or a 7-segment LED for displaying an input song code or the like.

  The video processing unit 16 combines the lyrics data with the background video data included in the song data or separately stored in the hard disk storage device 14 and displays the synthesized lyrics data on the monitor 30. Of course, other contents can be displayed.

[Configuration of Audio Processing Unit 20]
The sound processing unit 20 is connected to a CPU 21 that controls the operation of the entire sound processing unit 20 through a bus, a ROM 22, a RAM 23, a sound source unit 24, a 15-band equalizer (hereinafter simply referred to as an equalizer) 25, a voice effect unit 26, A frequency analysis unit 27 is connected.

  The CPU 21 of the audio processing unit 20 and the CPU 11 of the main control unit 10 are connected by USB (Universal Serial Bus). Therefore, in the processing described later, the target gain value and the determination gain value stored in the hard disk storage device 14 of the main control unit 10 are acquired via the CPU 11 of the main control unit 10 and stored in the RAM 23. . The ROM 22 stores an application program for controlling the operation of the sound processing unit 20.

  The tone generator 24 forms a (digital) tone signal based on the tone track data of the song data. The song data is read from the hard disk storage device 14 by the CPU 21 of the voice processing unit 20 via the CPU 11 of the main control unit 10 during karaoke performance. The tone track is composed of a plurality of tracks, and the tone generator 24 simultaneously forms a plurality of parts of tone signals based on this data. The musical sound signal formed by the sound source unit 24 is karaoke performance sound, and these are input to the equalizer 25. The equalizer 25 gives a predetermined acoustic effect to the karaoke performance sound. Specifically, the equalizer 25 divides the frequency band of 20 Hz to 20 kHz into 15 bands, and the sound of each frequency band. The gain value with respect to the pressure is changed in the range of −12 dB to +12 dB. The (digital) musical sound signal whose sound pressure frequency characteristic has been changed by the equalizer 25 is converted into an analog signal via a DA converter (not shown), mixed with a singing voice signal described later, and output to the speaker 40 which is an external device. Is done.

  On the other hand, a singing voice signal or sound signal input from a singing microphone 50 which is an external device is amplified by a microphone amplifier (not shown) and converted into a digital signal via an AD converter (not shown) to obtain a voice effect. To the unit 26 and the frequency analysis unit 27. The voice effect unit 26 gives an acoustic effect such as echo to the singing voice signal and outputs it. The singing voice signal output from the voice effect unit 26 is mixed with the musical sound signal and output to the speaker 40 as described above. Note that the voice effect unit 26 can be configured not to output a signal to the speaker 40. This is for the following reason. That is, when adjusting the sound pressure frequency characteristic of the reproduction sound field, so-called pink noise is generated from the sound source unit 24, pink noise generated from the speaker 40 is input by the microphone 50, and the frequency analysis unit 27 performs frequency conversion. To analyze. In this case, if the sound signal (pink noise) input by the microphone 50 is output from the speaker 40 again, inconvenience occurs. Therefore, when adjusting the sound pressure frequency characteristic, a signal is not output from the voice effect unit 26 to the speaker 40.

  The frequency analysis unit 27 performs frequency analysis on the input sound signal (pink noise) by FFT. In the present embodiment, like the 15 frequency bands in the equalizer 25, the frequency band of 20 Hz to 20 kHz is divided into 15 bands (bands), and the sound pressure in each frequency band is analyzed.

[Explanation of target gain value, judgment gain value, playback gain value, and equalizer gain value]
In the communication karaoke system of this embodiment, not only can the karaoke performance be executed at the communication karaoke terminal 1, but also the sound pressure frequency characteristics can be adjusted according to the environment in which the communication karaoke terminal 1 is installed. First, the necessity for such adjustment of the sound pressure frequency characteristic will be briefly described.

  In the online karaoke system, the actual situation is that the environment in which the online karaoke terminal 1 is installed to play and play music data is not uniform. Even if it is a karaoke box (room), the shape, size, and wall material are all different. For this reason, the sound pressure frequency characteristics (target sound pressure frequency characteristics) at the time of production of the music data and the sound pressure frequency characteristics (reproduction sound pressure frequency characteristics) in the playback environment such as in a karaoke box are greatly different. The sound condition intended by the creator cannot be reproduced sufficiently.

  In particular, let us examine the extent of the reproduced sound field. When considering a karaoke box or the like, the degree of breadth of the reproduction sound field is almost the same as the degree of breadth of the room.

  For example, FIG. 2A is a graph showing an example of how the sound pressure frequency characteristic varies depending on the size of the room. The measurement conditions are as follows. First, the same speaker and microphone are used, and the volume level of pink noise (reference audio signal) output from the speaker is common. Then, as shown in FIG. 2B, the distance L1 between the speaker and the microphone is fixed (for example, 45 cm), and the distance L2 between the microphone and the side wall is changed. Changing the distance L2 between the microphone and the side wall means changing the size of the room. In other words, even if the size of the room changes, the installation location of the karaoke equipment does not change much, and usually it is not installed in the center of the room but is moved to the corner. The location where the microphone is installed, that is, the location where the singing is performed, is determined to some extent based on the location where the karaoke equipment is installed. Therefore, if the size of the room changes, the distance L2 between the microphone and the side wall changes. Of course, it may be possible to consider the size of the room directly based on the floor area or the like, but here, in consideration of the use for karaoke, we focused on the distance L2 to the side wall on the basis of the microphone position.

  As for the distance L2 between the microphone and the side wall, for example, all the distances to the surrounding side walls may be taken into account. For simple determination, a speaker is installed on the premise of a rectangular room. It may be based only on the distance (from the microphone) to the side wall opposite to the side wall. FIG. 2 (a) shows the result of simple measurement under such conditions. As can be seen from the result of measuring the sound pressure frequency characteristic of FIG. 2A, a remarkable difference is observed around 30 Hz to 500 Hz. Therefore, the width of the room is also considered as an environment used to determine the sound quality that the data producer considers optimal when producing song data. Here, the room width is classified into three types (large, normal, and small), and pink noise (reference audio signal) is output in a situation where the room size is actually different, and this is input with a microphone. Performs frequency analysis (FFT) and, like the 15 frequency bands in the equalizer 25, divides the frequency band of 20Hz to 20kHz into 15 bands and analyzes the sound pressure in each frequency band for determination Adopted as a gain value. The waveforms (gain values) shown in FIGS. 3A to 3C are determination gain values when the room size is large, normal, and small, respectively. Note that the determination gain value is measured and set by the music data producer. For example, when the room size is large, normal, and small, each of the representative rooms has one representative room. The measurement result may be used, or an average value of actually measured values in a plurality of rooms may be employed. Even if it belongs to the category of a small room, its size and shape are slightly different, so it is also effective to reflect these differences.

  Then, a gain value (target gain value) for correcting the sound pressure frequency characteristic suitable for the size of each room having such a different degree of breadth and width is represented by a waveform as shown in FIGS. (Gain value). Although the determination gain value itself may be used as the target gain value, in this embodiment, further adjustment is added. This is based on the fact that the adjustment of the sound pressure frequency characteristic may actually be corrected according to the adjustment target. In other words, as described above, when obtaining a gain value for determination, a simple sound signal such as pink noise is output and measured, but the karaoke accompaniment sound output by an actual karaoke apparatus is a rather complicated sound. It is a signal. For this reason, for example, if there is a target sound pressure frequency characteristic that is considered more appropriate on the creator side of the karaoke music piece, it is preferable to set a gain value suitable for the target sound pressure frequency characteristic.

  In this way, as shown in FIGS. 3D to 3F, each of the three classified rooms is set in the “environment used to determine the sound quality that the data producer considers optimal”. A gain value (target gain value) for specifying the sound pressure frequency characteristic that provides the optimum sound quality is determined. Using this target gain value, the communication karaoke terminal 1 adjusts the sound pressure frequency characteristic.

  FIG. 4 shows an outline of the adjustment. 4A shows the target gain value, FIG. 4B shows the measured gain value, and FIG. 4C shows the gain value in the equalizer 25. For ease of understanding, FIG. 4A shows a flat waveform in which the gain values of all 15 bands are 0 dB. However, as described above, actually, FIGS. The target gain value is as shown in FIG.

  An outline of the adjustment will be described. It is assumed that the gain value (reproduction gain value) for specifying the sound pressure frequency characteristic actually measured in the environment where the communication karaoke terminal 1 is installed has a waveform (gain value) as shown in FIG. Since this reproduction gain value deviates from the target gain value shown in FIG. 4A, the equalizer 25 changes (adjusts) the gain value of the equalizer 25 so that they match. An example of the gain value of the equalizer 25 is shown in FIG. In the equalizer 25, the gain value in each of the 15 bands is determined by the bisection method, which is one of approximate calculation methods, using the target gain value and the reproduction gain value, or the reproduction gain value is subtracted from the target gain value. To get it. Note that, if the gain value of one band is corrected, there is an effect on the other bands. Therefore, correction is repeatedly performed for each of the 15 bands and finally matched (or approximated) to the target gain value.

  In this embodiment, the distribution host device 100 distributes a gain value for determination and a gain value (target gain value) for specifying a target sound pressure frequency characteristic to each communication karaoke terminal 1. In the environment where the terminal is actually installed, pink noise is generated from the sound source unit 24 to measure the gain value indicating the sound pressure frequency characteristic, and based on the measured gain value (reproduction gain value) and the determination gain value First, the reproduction sound field, that is, in this case, the degree of width of the room is determined. Then, the gain value in the equalizer 25 is changed (adjusted) to a value corresponding to the reproduction environment based on the difference between the target gain value corresponding to the determined degree of room width and the reproduction gain value. In other words, the gain value of the equalizer 25 is changed (adjusted) so that the measured value in the state where the gain value specifying the sound pressure frequency characteristic is adjusted and sounded by the equalizer 25 matches the above-described target gain value. .

[Explanation of operation executed in communication karaoke terminal 1]
Next, the operation performed in the communication karaoke system of the present embodiment will be described.
FIGS. 5 to 8 are flowcharts showing the processes executed in the communication karaoke terminal 1, which are processes (FIG. 5), start-up processes (FIG. 7), music selection / performance processes related to measurement and setting of the sound pressure frequency characteristics, respectively. It is a flowchart which shows (FIG. 8). These processes are executed jointly by the CPU 11 of the main control unit 10 and the CPU 21 of the sound processing unit 20. Hereinafter, it demonstrates in order.

[Measurement and setting processing of sound pressure frequency characteristics]
In the first step S10 in the flow chart of the sound pressure frequency characteristic measurement and setting process shown in FIG. 5, it is determined whether or not there is a mode switching input via the operation panel 15. This determines whether there is an input indicating an instruction to switch from the karaoke mode to the characteristic setting mode. If there is no mode switching input (S10: No), the determination of S10 is repeated, and if there is a mode switching input (S10: Yes), it is determined whether or not the target gain value exists in the hard disk storage device 14 (S20). ). If the target gain value does not exist in the hard disk storage device 14 (S20: No), the process returns to S10, but if the target gain value exists in the hard disk storage device 14 (S20: Yes), the process proceeds to S30.

  In S30, the karaoke mode is terminated and the characteristic setting mode is entered. In the next S40, notes such as a microphone set are displayed on the monitor 30 via the video processing unit 16. In accordance with this display, the adjustment operator performs setting of the microphone and the like, and when preparation is completed, preparation completion (OK) is input from the operation panel 15. If this OK is input (S50: Yes), the target gain value is determined according to the degree of the sound field (S60). The details of the subroutine processing relating to the determination of the target gain value in S60 will be described in more detail with reference to the flowchart of FIG.

[Target Gain Value Determination Process in FIG. 6]
First, the gain value is measured (S601). In measuring the gain value, the sound source unit 24 is instructed to start outputting pink noise. The pink noise output from the sound source unit 24 is generated from the speaker 40 via the equalizer 25 and a DA converter (not shown). In this way, the sound signal input from the microphone 50 with the pink noise output from the speaker 40 is subjected to frequency analysis (here, FFT) in the frequency analysis unit 27, and the result, that is, the reproduction gain value is expressed as audio. The data is stored in the RAM 23 of the processing unit 20. The frequency analysis unit 27 divides the input sound signal (pink noise) into a frequency band of 20 Hz to 20 kHz into 15 bands (bands) in the same manner as the 15 frequency bands in the equalizer 25, and each frequency band. Analyze the sound pressure. In addition, since the sound signal (pink noise) input by the microphone 50 is output from the speaker 40 again during the measurement / setting processing of the sound pressure frequency characteristics, inconvenience occurs. Is not output.

  On the other hand, the determination gain values (in this embodiment, three types of determination gain values shown in FIGS. 3A to 3C) are read from the hard disk storage device 14 to the RAM 23 of the sound processing unit 20, and Differences between the reproduction gain value, which is the frequency analysis result, and the three types of determination gain values are calculated (S602). Then, based on the difference from these three types of determination gain values, the size of the room (degree of breadth and narrowness) is determined (S603). Here, depending on which of the three types of determination gain values corresponds to the difference having the smallest absolute value, it is determined whether it corresponds to “large”, “normal”, or “small” (S604). The process proceeds to S605, S606, and S607 according to the determination result. That is, the target gain value for “large room” is set in S605, the target gain value for “normal room” is set in S606, and the target gain value for “small room” is set in S607. Specifically, since three types of target gain values are stored in the hard disk storage device 14 of the main control unit 10, one of the corresponding target gain values is read out and the RAM 23 of the sound processing unit 20 is read out. Remember me.

When the subroutine shown in FIG. 6 ends, the process proceeds to S70 in FIG.
In S70, the gain value is measured. The measurement of the gain value is the same as the process of S601 in FIG. 6 described above. Pink noise generated from the speaker 40 is input from the microphone 50 and the frequency analysis unit 27 performs frequency analysis of 15 bands. The result, that is, the reproduction gain value is stored in the RAM 23 of the sound processing unit 20.

  On the other hand, the target gain value is read from the hard disk storage device 14 to the RAM 23 in S60 described above, and the gain value of the equalizer 25 is changed based on the reproduction gain value and the target gain value that are the frequency analysis results ( S80). In the present embodiment, a dichotomy method, which is one of approximate calculation methods by a computer, is used, and the gain value of the equalizer 25 in each band is determined based on the target gain value and the reproduction gain value. The details of the subroutine processing relating to the gain value change in S80 will be described in more detail with reference to the flowchart of FIG.

[Gain value change processing in FIG. 7]
First, it is determined whether or not the absolute value of the value obtained by subtracting the reproduction gain value Y in each band from the target gain value X in each band is 1 dB or more. If | X−Y | <1 (S801: No), this subroutine is terminated without executing the processing of S802 and subsequent steps. That is, if the difference between the target gain value X and the reproduction gain value Y is relatively small, it means that the gain value change itself of the equalizer 25 is not performed. On the other hand, if | X−Y | ≧ 1 (S801: Yes), the process proceeds to S802, where it is determined whether the target gain value X is larger than the reproduction gain value Y.

  If X> Y (S802: Yes), (| XY | / 2) is added to the gain value Z of the equalizer 25 in each current band (S803). Then, it is determined whether or not the gain value Z of the equalizer 25 after the addition in S803 is larger than 12 dB (S804). Since the adjustment range of the equalizer 25 of the present embodiment is ± 12 dB, when the calculation result Z> 12 dB in S803 (S804: Yes), the equalizer maximum 25 dB is set as the maximum positive adjustment value. (S805), and this subroutine is finished. Further, when Z ≦ 12 dB (S804: No), it is not necessary to perform the restriction as in S805, and thus this subroutine is terminated as it is. That is, the gain value Z of the equalizer 25 set in S803 is applied as it is.

  On the other hand, if X ≦ Y (S802: No), (| X−Y | / 2) is subtracted from the current gain value Z of the equalizer 25 (S806). Then, it is determined whether or not the gain value Z of the equalizer 25 after subtraction in S806 is smaller than −12 dB (S807). Since the adjustment range of the equalizer 25 of this embodiment is ± 12 dB, if the calculation result Z <−12 dB in S806 (S807: Yes), −12 dB which is the maximum negative adjustment value is uniformly set to −12 dB. The gain value Z of the equalizer 25 is set (S808), and this subroutine is terminated. If Z ≧ −12 dB (S807: No), there is no need to perform the restriction as in S808, and the subroutine is terminated as it is. That is, the gain value Z of the equalizer 25 set in S806 is applied as it is.

  In the present embodiment, the gain value of the equalizer 25 is determined using a bisection method as shown in FIG. 7, but even if other than the bisection method, for example, the reproduction gain value is subtracted from the target gain value. The gain value may be determined. As another similar method of the bisection method, a positive real number larger than 0 and smaller than 2 in this embodiment instead of (| X−Y | / 2) in S803 or S806 in FIG. 1 (unit dB)) and a method of convergence can be adopted, and the gain value of the equalizer 25 can be obtained using various methods of approximate calculation by a computer.

  When the subroutine shown in FIG. 7 ends, the process proceeds to S90 in FIG. In S90, it is determined whether or not a fixed time has passed. Until the fixed time has passed (S90: No), the process of measuring the gain value in S70 and changing the gain value in S80 is repeated.

  When a predetermined time has elapsed (S90: Yes), the sound source unit 24 is controlled to stop the output of pink noise (S100), and the current gain value of the equalizer 25 is recorded in the hard disk storage device 14 (S110). It should be noted that the fixed times in S70 and S90 are desirably set to values such that the fixed time in S70 is 0.5 seconds and the fixed time in S90 is 60 seconds, for example. Then, the monitor 30 displays that the sound pressure frequency characteristic measurement / setting process has been completed (S120), and returns to the karaoke mode (S130). Thereafter, the process proceeds to S10.

By executing the processing as described above, the gain value in the equalizer 25 can be changed (adjusted) to a value according to the reproduction environment in consideration of the degree of width of the reproduction sound field.
[Start process]
In the first step S210 in the flowchart of the activation process shown in FIG. 8, various initialization processes are executed. This includes, for example, reset of hardware (modem 12, operation panel 15, video processing unit 16, etc.), confirmation of program version, setting of volume level, and the like.

  Then, it is determined whether or not the gain value is recorded in the hard disk storage device 14 (S220). If the gain value is recorded in the hard disk storage device 14 (S220: Yes), the gain value in the equalizer 25 is stored in the hard disk. Settings are made as recorded in the device 14 (S230). Then, the karaoke mode is started (S250). Therefore, when performing in this karaoke mode, the gain value in the equalizer 25 is adjusted in accordance with the playback environment, and is set in the “environment used to determine the sound quality that the data producer considers optimal”. Thus, karaoke performance is realized in a state that matches or approximates the target gain value for specifying the sound pressure frequency characteristic that provides the optimum sound quality.

  On the other hand, if the gain value is not recorded in the hard disk storage device 14 (S220: No), the gain value in the equalizer 25 is set to be flat (specifically, the gain values of each band are all 0) (S240). Then, it transfers to S250 and starts karaoke mode.

  When the karaoke mode is started, if there is a karaoke song number input via the operation panel 15, the corresponding song data is acquired from the hard disk storage device 14. Then, the karaoke performance is executed using the acquired music data.

[Explanation of operations when receiving distribution of song data and target gain value data]
Next, the operation when the data karaoke terminal 1 distributes the data file including the song data, the target gain value, and the determination gain value from the distribution host device 100 in the communication karaoke system of the present embodiment will be described.

  In this embodiment, when the distribution host device 100 distributes the song data to the communication karaoke terminal 1, the target gain value and the determination gain value are also distributed. The distribution pattern includes a pattern in which the song data is distributed after distributing the target gain value and the determination gain value, a pattern in which the target gain value and the determination gain value are distributed after the distribution of the song data, and the distribution host device 100 performs the distribution. The data, the target gain value, and the determination gain value are encapsulated as one data file, and the song data, the target gain value, and the determination gain value are simultaneously distributed to the communication karaoke terminal 1. There are three patterns that can be divided into song data, target gain values, and determination gain values.

The distribution may be a terminal call or a host call.
The general operation in the case of the terminal call type is as follows. The communication karaoke terminal 1 determines whether or not a predetermined time programmed as a time for downloading from the distribution host device 100 in advance is reached, and when the download time is reached, a call is made to the distribution host device 100. And establish a connection. Then, the distribution host device 100 transmits the file list held in the hard disk storage device 104 to the communication karaoke terminal 1, and the communication karaoke terminal 1 checks in order from the first file name in the file list and performs communication. If not held in the hard disk storage device 14 of the karaoke terminal 1, the distribution host device 100 is requested to distribute the corresponding file. The distribution host device 100 transmits the file requested from the communication karaoke terminal 1 to the communication karaoke terminal 1.

  On the other hand, the general operation in the case of the host call type is as follows. The distribution host device 100 determines whether or not a predetermined time programmed as a time for distribution to the communication karaoke terminal 1 has been reached in advance, and if the distribution time has been reached, specifies the communication karaoke terminal 1 to be distributed. Terminal information for each location is obtained in order from the top of the terminal list (in this case, serial number + telephone number), and a call is established to the corresponding communication karaoke terminal 1 to establish a connection. To do. When the connection with the communication karaoke terminal 1 is established in S740, the distribution host device 100 transmits the file list held in the hard disk storage device 104 to the communication karaoke terminal 1. The communication karaoke terminal 1 receives the file list transmitted from the distribution host device 100, checks the file list in order from the first file name, and holds it in the hard disk storage device 14 of the communication karaoke terminal 1. For example, the distribution host device 100 is requested to distribute the corresponding file. The distribution host device 100 transmits the file requested from the communication karaoke terminal 1 to the communication karaoke terminal 1.

[Effect of Example]
(A) Each communication karaoke terminal 1 stores a plurality of (three types in this embodiment) determination gain values and target gain values set in accordance with the degree of sound field width. Then, by comparing the reproduction gain value with a plurality of determination gain values, the degree of width of the reproduction sound field is determined. This determination can be made based on the determination gain value corresponding to the minimum difference absolute value among the absolute values of the differences between the reproduction gain value and the plurality of determination gain values. Thus, when the degree of width of the room increases, the analysis result of the sound pressure frequency characteristic for the same measurement sound signal differs. Therefore, if this is compared with the actual measurement value of the sound pressure frequency characteristic in the reproduction sound field as a determination gain value, the degree of width of the room in the reproduction sound field can be easily determined. If the degree of room width can be determined in this way, the gain value of the equalizer is adjusted so that the reproduction gain value matches the target gain value corresponding to the determined degree of width. Since this target gain value is in accordance with the extent of the room, appropriate adjustment of the sound pressure frequency characteristic in accordance with the extent of the reproduced sound field can be realized.

  (B) In this embodiment, the determination gain value and the target gain value are distributed from the distribution host device 100 to the communication karaoke terminal 1, and the communication karaoke terminal 1 has a wide and narrow reproduction sound field based on the determination gain value. The degree is determined, and the gain value of the equalizer 25 is adjusted so as to coincide with the target gain value determined based on the degree. That is, the communication karaoke terminal itself performs the determination of the degree of width of the reproduction sound field and the gain value adjustment. Therefore, even if, for example, tens of thousands of communication karaoke terminals 1 are connected to one distribution host device 100, the degree of breadth of the reproduction sound field in which the communication karaoke terminal 1 is installed in the distribution host device 100 And processing for gain value adjustment in the communication karaoke terminal 1 is not executed, so that no processing load is applied.

  (C) The target gain value is a gain value for specifying a “recommended” sound pressure frequency characteristic, which the creator of the karaoke music thinks is “preferably such a sound pressure frequency characteristic”. Therefore, the target gain value once determined may be changed by subsequent examination. Even in such a case, if the target gain value after the change is distributed from the distribution host device 100 to the communication karaoke terminal 1, the gain value adjustment is executed at each communication karaoke terminal 1, and it is very convenient. It is.

  Also, the degree of room width is three types in the present embodiment, but it may be two types, and can be further classified. For example, when the classification is increased to four types, the determination gain value and the target gain value are each set to four types. Even in this case, if the changed determination gain value and target gain value are distributed from the distribution host device 100 to the communication karaoke terminal 1, the degree of the reproduction sound field at each communication karaoke terminal 1 thereafter This determination and the gain value adjustment are executed, which is very convenient.

[Another embodiment]
(1) In the above-described embodiment, the actually measured value is used as the determination gain value, and the determination gain value is further modified to obtain the target gain value. However, for convenience, these may be the same value. In that case, it is only necessary to store a gain value that is both a determination gain value and a target gain value, and the storage capacity is about half.

(2) In the above embodiment, pink noise for measurement is generated from the sound source unit 24. However, for example, a pink noise generation unit may be provided separately from the sound source unit 24.
(3) In the above embodiment, the frequency analysis unit 27 performs frequency analysis using FFT in order to grasp the sound pressure frequency characteristics. However, instead of using FFT, for example, a band pass filter and a peak value detector may be provided for each band, and the sound pressure frequency characteristic may be measured at the peak value of each band.

  (4) In the above embodiment, the example realized as a so-called communication karaoke system has been described, but the terminal device may be other than the karaoke terminal.

It is a block diagram which shows the structure of the communication karaoke system as one Example of an information communication system. It is explanatory drawing which shows an example of how a sound pressure frequency characteristic changes with the difference in the magnitude | size of a room. It is explanatory drawing which shows the specific example of the gain value for a determination according to the size of a room, and a target gain value. It is explanatory drawing which shows the example of the gain value of a target gain value, a reproduction | regeneration gain value, and an equalizer based on them. It is a flowchart which shows the process which concerns on the measurement and setting of a sound pressure frequency characteristic. It is a flowchart which shows the gain value change process performed in S60 of FIG. It is a flowchart which shows the gain value change process performed in S80 of FIG. It is a flowchart which shows starting processing

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Communication karaoke terminal, 10 ... Main control part, 11 ... CPU, 12 ... Modem, 13 ... RAM, 14 ... Hard disk storage device, 15 ... Operation panel, 16 ... Image processing part, 20 ... Audio | voice processing part, 21 ... CPU 22 ... ROM, 23 ... RAM, 24 ... sound source unit, 25 ... equalizer, 26 ... voice effect unit, 27 ... frequency analysis unit, 30 ... monitor, 40 ... speaker, 50 ... microphone, 90 ... general public network or Internet 100: Distribution host device, 101: CPU, 102: ROM, 103: RAM, 104: Hard disk storage device, 105: Communication control unit.

Claims (8)

A measurement sound signal generating means for generating a measurement sound signal;
An equalizer capable of changing the sound pressure frequency characteristic of the measurement sound signal generated from the measurement sound signal generating means by changing the gain value;
A sounding means for emitting the output from the equalizer as an audible sound;
Sound input means for inputting an audible sound emitted from the sound generation means and converting it into an electrical signal;
Based on the electrical signal from the sound input means, an analysis means for analyzing a gain value that identifies the sound pressure frequency characteristics;
A determination gain value storage means for storing a gain value (hereinafter referred to as a determination gain value) for specifying a plurality of determination sound pressure frequency characteristics set in accordance with the degree of width of the sound field;
A gain value (hereinafter referred to as a reproduction gain value) for specifying a sound pressure frequency characteristic in a reproduction sound field, which is an analysis result by the analysis unit, and a plurality of determination gain values stored in the determination gain value storage unit By comparing the width and width of the reproduction sound field,
A target gain value storage means for storing a gain (hereinafter referred to as a target gain value) for specifying a plurality of target sound pressure frequency characteristics set according to the degree of width of the sound field;
A target gain value corresponding to the degree of width determined by the width determination means is read from the target gain value storage means, and a target corresponding to the degree of width determined by the width determination means based on the read target gain value. Gain value adjusting means for adjusting the gain value of the equalizer so that the sound pressure frequency characteristic in the reproduction sound field matches the sound pressure frequency characteristic;
A sound pressure frequency characteristic adjusting device comprising: In the sound pressure frequency characteristic adjusting device according to claim 1,
The sound pressure frequency characteristic adjusting device according to claim 1, wherein the determination gain value is set according to a degree of width of the sound field determined by a distance between a side wall of a room constituting the sound field and the sound input means. In the sound pressure frequency characteristic adjusting device according to claim 1 or 2,
The equalizer can change the gain value for each frequency band divided into a plurality of parts to change the sound pressure frequency characteristics,
The sound pressure frequency characteristic adjusting device, wherein the determination gain value and the target gain value are also set for each of the frequency bands divided into the plurality. In the sound pressure frequency characteristic adjusting device according to any one of claims 1 to 3,
The determination gain value and the target gain value are the same value,
The sound pressure frequency characteristic, wherein the storage means that is also the determination gain value storage means and the target gain value storage means stores a gain value that is both the determination gain value and the target gain value. Adjustment device. A plurality of terminal devices including the sound pressure frequency characteristic adjusting device according to claim 1 and a distribution host device, wherein the distribution host device and the terminal device are mutually connected via a communication line. An information communication system configured to be capable of information communication,
The distribution host device includes distribution control means for distributing the determination gain value and the target gain value to the terminal device,
The breadth / narrowness determination means of the terminal device determines a degree of breadth / width of the reproduction sound field based on the determination gain value distributed from the distribution host device,
The information communication system, wherein the gain value adjusting means of the terminal device adjusts the gain value of the equalizer based on the target gain value distributed from the distribution host device. The information communication system according to claim 5, wherein
The information communication system, wherein the communication line is a general public line network or the Internet. The information communication system according to claim 5 or 6,
The terminal device
Data storage means for storing music data;
Music reproduction means for performing music reproduction based on the music data stored in the data storage means,
The distribution control means of the distribution host device comprises:
The information communication system, wherein the determination gain value and the target gain value are distributed when the music data is distributed to the terminal device. 5. The measurement sound signal generating means, equalizer, sound input means, analysis means, determination gain value storage means, wide / narrow determination means, target gain value storage means, gain value according to claim 1 In the sound pressure frequency characteristic adjusting device comprising the adjusting means, a program executed by a computer provided in the sound pressure frequency characteristic adjusting device,
A program for causing the computer to function as the analysis means, the wide / decrease determination means, and the gain value adjustment means provided in the sound pressure frequency characteristic adjustment device according to any one of claims 1 to 4.

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