Acoustic design support apparatus

• US 20070019823A1
• Filed: 07/19/2006
• Published: 01/25/2007
• Est. Priority Date: 07/19/2005
• Status: Active Grant

• Current Assignee: Yamaha Corporation
• Original Assignee: Yamaha Corporation
• Inventors: Watanabe, Takayuki, Sakanashi, Hideki, Miyazaki, Hideo, Matsumoto, Shuichi
• Granted Patent: US 7,773,768 B2
• Time in Patent Office: Days
• US Class Current: 381/87
• CPC Class Codes: H04S 7/301 Automatic calibration of stereophonic sound system, e.g. with test microphone
• CPC Class Codes: H04S 7/302 Electronic adaptation of stereophonic sound system to listener position or orientation H04S7/301 takes precedence
• CPC Class Codes: H04S 7/307 Frequency adjustment, e.g. tone control H04S7/301 takes precedence

Abstract

In an acoustic design support apparatus, a speaker selection supporter selects a desired speaker as a candidate for use in a given space based on shape information representing a shape of the space. A speaker mounting angle optimizer calculates an optimal mounting direction of the selected speaker by selecting a mounting direction pattern which minimizes a degree of variation among sound pressure levels at a plurality of positions on a sound receiving surface defined in the space. An acoustic parameter calculator calculates a variety of acoustic parameters at sound receiving points within the space based on both of the shape information of the space and the optimal mounting direction of the speaker.

Claims

1. An acoustic design support apparatus comprising:

a speaker selection supporter that selects a desired speaker as a candidate for use in a given space based on shape information representing a shape of the space;

a speaker mounting angle optimizer that calculates an optimal mounting direction of the selected speaker by selecting a mounting direction pattern which minimizes a degree of variation among sound pressure levels at a plurality of positions on a sound receiving surface defined in the space; and

an acoustic parameter calculator that calculates a variety of acoustic parameters at sound receiving points within the space based on both of the shape information of the space and the optimal mounting direction of the speaker.

2. The acoustic design support apparatus according to claim 1, wherein the acoustic parameter calculator calculates the acoustic parameters from a response at each sound receiving point, the response being obtained by a convolution-based calculation of speaker characteristics data, equalizer characteristics data and filter characteristics data in a frequency domain, wherein

the speaker characteristics data is previously produced through Fourier transform of data of actually measured values of impulse responses in all directions of the speaker,

the equalizer characteristics data is previously produced through Fourier transform of data of an equalizer used to adjust frequency characteristics of the speaker, and

the filter characteristics data is previously produced through Fourier transform of filter data for phase correction due to a time delay and filter data for attenuation correction due to an attenuation, the time delay and the attenuation being caused by a distance between the sound receiving point and a sound source point defined in the space.

3. The acoustic design support apparatus according to claim 1, wherein the acoustic parameter calculator calculates the acoustic parameters which represent at least one of characteristics of sound pressure levels of the sound receiving surface, a distribution of the sound pressure levels along the sound receiving surface, and impulse responses of the sound receiving surface,

the acoustic design support apparatus further comprising a data output unit that outputs the calculated acoustic parameters to a display connected to the acoustic design support apparatus.

4. An acoustic design support apparatus for calculating optimal mounting angles of a plurality of speaker units included in an array speaker for use in a given space, the apparatus comprising:

a pattern setter that sets a plurality of mounting angle patterns, each mounting angle pattern corresponding to a combination of specific mounting angles of the speaker units;

a sound pressure level variation degree calculator that performs, for each of the set mounting angle patterns, an axis point position calculation process for calculating positions of axis points at which a sound receiving surface defined in the space intersects axis lines of the speaker units at the specific mounting angles, an equalizer parameter calculation process for determining equalizer parameters of the speaker units which minimize a degree of variation among frequency characteristics of sound pressure levels at the axis points, and a sound pressure level variation degree calculation process for obtaining a degree of variation among the sound pressure levels at a plurality of positions previously set on the sound receiving surface based on the determined equalizer parameters and frequency characteristics of each speaker unit; and

a pattern selector that selects one of the set mounting angle patterns, which minimizes the degree of variation of the sound pressure levels at the plurality of the positions, as an optimal mounting angle pattern which determines the mounting angles of the speaker units of the array speaker.

5. The acoustic design support apparatus according to claim 4, which repeatedly activates the pattern setter, the pressure level variation degree calculator, and the pattern selector in an iterative manner, wherein

the pattern setter sets the plurality of the mounting angle patterns at intervals of a coarse angle in a first iterative loop, and resets a plurality of fine mounting angle patterns in a second iterative loop at intervals of a fine angle around at least one mounting angle pattern providing a small degree of variation of the sound pressure levels among the plurality of the mounting angle patterns set in the first iterative loop, and wherein

the pattern selector selects one of the fine mounting angle patterns providing a minimum degree of variation of the sound pressure levels from among the plurality of the fine mounting angle patterns reset in the second iterative loop, as an optimal mounting angle pattern of the speaker units of the array speaker.

6. The acoustic design support apparatus according to claim 4, wherein the sound pressure level variation degree calculator performs the equalizer parameter calculation process including:

setting equalizer gain patterns corresponding to combinations of gain setting levels of the speaker units at each channel frequency of an equalizer used to control frequency characteristics of sound signals fed to the speaker units; and

calculating, independently for each channel frequency, the equalizer parameters of the speaker units by selecting one equalizer gain pattern from among the set equalizer gain patterns, the selected equalizer gain pattern minimizing a degree of variation of the gains at the respective axis points of the speaker units.

7. An acoustic design support apparatus comprising:

a speaker selection data storage that previously stores a data table in which a variety of speaker data representing characteristics of speakers are written;

a space shape input unit that receives shape information inputted to select a schematic shape of a space and numerical information inputted to specify characteristics of the schematic shape; and

a speaker selection supporter that selects a speaker as a candidate for use in the space, based on the shape information and the numerical information inputted through the space shape input unit by comparing the inputted shape information and the numerical information with the speaker data of the data table of the speakers, and that outputs the candidate to a display connected to the acoustic design support apparatus.

8. The acoustic design support apparatus according to claim 7, wherein the space shape input unit receives the space information specifying either of a fan shape and a box shape as the schematic shape of the space.

9. The acoustic design support apparatus according to claim 7, wherein the data table is written with at least an allowable range of an area size of the space for each speaker and an allowable range of a planar shape aspect ratio of the space for each speaker, and wherein

the speaker selection supporter calculates an area size and a planar shape aspect ratio of the space based on the shape information and the numerical information inputted through the space shape input unit, and determines whether or not the calculated area size and planar shape aspect ratio correspond to the allowable range of the area size of the space for each speaker and the allowable range of the planar shape aspect ratio of the space for each speaker so as to select the speaker which meets the allowable ranges.

10. A machine readable medium containing an acoustic design support program which is executable by a computer to perform:

a speaker selection support step of selecting a desired speaker as a candidate for use in a given space based on shape information representing a shape of the space;

a speaker mounting angle optimization step of calculating an optimal mounting direction of the selected speaker by selecting a mounting direction pattern which minimizes a degree of variation among sound pressure levels at a plurality of positions on a sound receiving surface defined in the space; and

an acoustic parameter calculation step of calculating a variety of acoustic parameters at sound receiving points within the space based on both of the shape information of the space and the optimal mounting direction of the speaker.

12. The machine readable medium according to claim 10, wherein the acoustic parameter calculating step calculates the acoustic parameters, which represent at least one of characteristics of sound pressure levels of the sound receiving surface, a distribution of the sound pressure levels along the sound receiving surface, and impulse responses of the sound receiving surface,

the acoustic design support program further comprising a data output step of outputting the calculated acoustic parameters to a display connected to the computer.

11. The machine readable medium, wherein the acoustic parameter calculation step calculates the acoustic parameters from a response at each sound receiving point, the response being obtained by a convolution-based calculation of speaker characteristics data, equalizer characteristics data and filter characteristics data in a frequency domain, wherein

the speaker characteristics data is previously produced through Fourier transform of data of actually measured values of impulse responses in all directions of the speaker,

the equalizer characteristics data is previously produced through Fourier transform of data of an equalizer used to adjust frequency characteristics of the speaker, and

the filter characteristics data is previously produced through Fourier transform of filter data for phase correction due to a time delay and filter data for attenuation correction due to an attenuation, the time delay and the attenuation being caused by a distance between the sound receiving point and a sound source point defined in the space.

13. A machine readable medium containing an acoustic design support program for calculating optimal mounting angles of a plurality of speaker units included in an array speaker for use in a given space, wherein the program is executable by a computer to perform:

1) a pattern setting step of setting a plurality of mounting angle patterns, each mounting angle pattern corresponding to a combination of specific mounting angles of the speaker units;

2) a sound pressure level variation degree calculation step being performed for each of the set mounting angle patterns, the variation degree calculation step including;

2-1) an axis point position calculation step of calculating positions of axis points at which a sound receiving surface defined in the space intersects axis lines of the speaker units at the specific mounting angles;

2—

2) an equalizer parameter calculation step of determining equalizer parameters of the speaker units which minimize a degree of variation among frequency characteristics of sound pressure levels at the axis points; and

2-3) a sound pressure level variation degree calculation step of obtaining a degree of variation among the sound pressure levels at a plurality of positions previously set on the sound receiving surface based on the determined equalizer parameters and frequency characteristics of each speaker unit; and

3) a pattern selecting step of selecting one of the set mounting angle patterns, which minimizes the degree of variation of the sound pressure levels at the plurality of the positions on the sound receiving surface, as an optimal mounting angle pattern for determining the mounting angles of each of the speaker units of the array speaker.

14. The machine readable medium according to claim 13, wherein the acoustic design support program is repeatedly executed to perform the pattern setting step, the pressure level variation degree calculation step, and the pattern selecting step in an iterative manner, wherein

the pattern setting step sets the plurality of the mounting angle patterns at intervals of a coarse angle in a first iterative loop, and resets a plurality of fine mounting angle patterns in a second iterative loop at intervals of a fine angle around at least one mounting angle pattern providing a small degree of variation of the sound pressure levels among the plurality of the mounting angle patterns set in the first iterative loop, and wherein

the pattern selecting step selects one of the fine mounting angle patterns providing a minimum degree of variation of the sound pressure levels from among the plurality of the fine mounting angle patterns reset in the second iterative loop, as an optimal mounting angle pattern of the speaker units of the array speaker.

15. The machine readable medium according to claim 13, wherein the equalizer parameter calculation step includes:

setting equalizer gain patterns corresponding to combinations of gain setting levels of the speaker units at each channel frequency of an equalizer used to control frequency characteristics of sound signals fed to the speaker units; and

calculating, independently for each channel frequency, the equalizer parameters of the speaker units by selecting one equalizer gain pattern from among the set equalizer gain patterns, the selected equalizer gain pattern minimizing a degree of variation of gains at the respective axis points of the speaker units.

16. A machine readable medium containing an acoustic design support program executable by a computer having a data storage which stores a data table containing a variety of speaker data representing characteristics of speakers, for performing:

a space shape input step of receiving shape information inputted to select a schematic shape of a space and numerical information inputted to specify characteristics of the schematic shape; and

a speaker selection support step of selecting one of the speakers as a candidate for use in the space, based on the inputted shape information and numerical information by comparing the inputted shape information and numerical information with the speaker data of the speakers contained in the data table, and outputting the candidate to a display connected to the computer.

17. The machine readable medium according to claim 16, wherein the space shape input step includes receiving the shape information specifying either of a fan shape and a box shape as the schematic shape of the space.

18. The machine readable medium according to claim 16, wherein the data table is written with at least an allowable range of an area size of the space for each speaker and an allowable range of a planar shape aspect ratio of the space for each speaker, and wherein

the speaker selection support step calculates an area size and a planar shape aspect ratio of the space based on the inputted shape information and numerical information, and determines whether or not the calculated area size and planar shape aspect ratio correspond to the allowable range of the area size of the space for each speaker and the allowable range of the planar shape aspect ratio of the space for each speaker so as to select the speaker which meets the allowable ranges.

19. An acoustic design support method comprising:

a speaker selection support step of selecting a desired speaker as a candidate for use in a given space based on shape information representing a shape of the space;

a speaker mounting angle optimization step of calculating an optimal mounting direction of the selected speaker by selecting a mounting direction pattern which minimizes a degree of variation among sound pressure levels at a plurality of positions on a sound receiving surface defined in the space; and

an acoustic parameter calculation step of calculating a variety of acoustic parameters at sound receiving points within the space based on both of the shape information of the space and the optimal mounting direction of the speaker.

20. The acoustic design support method according to claim 19, wherein the acoustic parameter calculation step calculates the acoustic parameters from a response at each sound receiving point, the response being obtained by a convolution-based calculation of speaker characteristics data, equalizer characteristics data and filter characteristics data in a frequency domain, wherein

the speaker characteristics data is previously produced through Fourier transform of data of actually measured values of impulse responses in all directions of the speaker,

the equalizer characteristics data is previously produced through Fourier transform of data of an equalizer used to adjust frequency characteristics of the speaker, and

the filter characteristics data is previously produced through Fourier transform of filter data for phase correction due to a time delay and filter data for attenuation correction due to an attenuation, the time delay and the attenuation being caused by a distance between the sound receiving point and a sound source point defined in the space.

21. The acoustic design support method according to claim 19, wherein the acoustic parameter calculating step calculates the acoustic parameters, which represent at least one of characteristics of sound pressure levels of the sound receiving surface, a distribution of the sound pressure levels along the sound receiving surface, and impulse responses of the sound receiving surface,

the acoustic design support program further comprising a data output step of outputting the calculated acoustic parameters to a display connected to the computer.

22. An acoustic design support method for calculating optimal mounting angles of a plurality of speaker units included in an array speaker for use in a given space, the method comprising:

1) a pattern setting step of setting a plurality of mounting angle patterns, each mounting angle pattern corresponding to a combination of specific mounting angles of the speaker units;

2) a sound pressure level variation degree calculation step being performed for each of the set mounting angle patterns, the variation degree calculation step including;

2-1) an axis point position calculation step of calculating positions of axis points at which a sound receiving surface defined in the space intersects axis lines of the speaker units at the specific mounting angles;

2—

2) an equalizer parameter calculation step of determining equalizer parameters of the speaker units which minimize a degree of variation among frequency characteristics of sound pressure levels at the axis points; and

2-3) a sound pressure level variation degree calculation step of obtaining a degree of variation among the sound pressure levels at a plurality of positions previously set on the sound receiving surface based on the determined equalizer parameters and frequency characteristics of each speaker unit; and

3) a pattern selecting step of selecting one of the set mounting angle patterns, which minimizes the degree of variation of the sound pressure levels at the plurality of the positions on the sound receiving surface, as an optimal mounting angle pattern for determining the mounting angles of each of the speaker units of the array speaker.

23. The acoustic design support method according to claim 22, which is repeatedly executed to perform the pattern setting step, the pressure level variation degree calculation step, and the pattern selecting step in an iterative manner, wherein

the pattern setting step sets the plurality of the mounting angle patterns at intervals of a coarse angle in a first iterative loop, and resets a plurality of fine mounting angle patterns in a second iterative loop at intervals of a fine angle around at least one mounting angle pattern providing a small degree of variation of the sound pressure levels among the plurality of the mounting angle patterns set in the first iterative loop, and wherein

the pattern selecting step selects one of the fine mounting angle patterns providing a minimum degree of variation of the sound pressure levels from among the plurality of the fine mounting angle patterns reset in the second iterative loop, as an optimal mounting angle pattern of the speaker units of the array speaker.

24. The acoustic design support method according to claim 22, wherein the equalizer parameter calculation step includes:

setting equalizer gain patterns corresponding to combinations of gain setting levels of the speaker units at each channel frequency of an equalizer used to control frequency characteristics of sound signals fed to the speaker units; and

calculating, independently for each channel frequency, the equalizer parameters of the speaker units by selecting one equalizer gain pattern from among the set equalizer gain patterns, the selected equalizer gain pattern minimizing a degree of variation of gains at the respective axis points of the speaker units.

25. An acoustic design support method comprising:

a speaker selection data storing step of previously storing a data table in which a variety of speaker data representing characteristics of speakers are written;

a space shape input step of receiving shape information inputted to select a schematic shape of a space and numerical information inputted to specify characteristics of the schematic shape; and

a speaker selection support step of selecting one of the speakers as a candidate for use in the space, based on the inputted shape information and numerical information by comparing the inputted shape information and numerical information with the speaker data of the speakers contained in the data table, and outputting the candidate to a display connected to the computer.

26. The acoustic design support method according to claim 25, wherein the space shape input step includes receiving the shape information specifying either of a fan shape and a box shape as the schematic shape of the space.

27. The acoustic design support method according to claim 25, wherein the data table is written with at least an allowable range of an area size of the space for each speaker and an allowable range of a planar shape aspect ratio of the space for each speaker, and wherein

the speaker selection support step calculates an area size and a planar shape aspect ratio of the space based on the inputted shape information and numerical information, and determines whether or not the calculated area size and planar shape aspect ratio correspond to the allowable range of the area size of the space for each speaker and the allowable range of the planar shape aspect ratio of the space for each speaker so as to select the speaker which meets the allowable ranges.