Sound direction system

• US 7,480,389 B2
• Filed: 03/07/2002
• Issued: 01/20/2009
• Est. Priority Date: 03/07/2001
• Status: Expired due to Term

• Current Assignee: Apple Inc.
• Original Assignee: Harman International Industries Incorporated (Samsung Electronics Co. Ltd.)
• Inventors: Ricks, Bradley Joel, Rutkin, Andrew
• Primary Examiner(s): Ni; Suhan
• Assistant Examiner(s): Flanders; Andrew C
• Application Number:
  US10/093,230
• Publication Number:
  US 20020125066A1
• Time in Patent Office: 2,511 Days
• Field of Search: 381/335, 381/89, 381/182, 381/186
• US Class Current: 381/335
• CPC Class Codes: G10K 11/346 using phase variation
• CPC Class Codes: H04S 1/002 Non-adaptive circuits, e.g. manually adjustable or static, for enhancing the sound image or the spatial distribution control circuits for electronic adaptation of the sound field H04S7/30

Abstract

This invention provides a sound source system capable of producing a desired coverage pattern with high SPL that may be steered towards a desired listening area. The sound source system may provide an array of sound sources where the coverage pattern and SPL may depend on the height, width, and depth of the assembled array. Adding height and width to the array may narrow the vertical and horizontal coverage patterns that are projected, respectively. To maintain a substantially constant coverage pattern, a frequency shading techniques may be used to keep the height of the array constant relative to the wavelength. Adding depth to the array may provide greater SPL with minimal effect on the coverage pattern because array'"'"'s height and width have not changed. The sound source system may also coherently sum in the main lobe and provide substantial off-axis rejection. This may be done using an end-fired related principle where each sound source in the array may be delayed proportional to its delay distance. The delay distance for each sound source may be the shortest distance between the sound source and the reference plane. This allows the sound source system to provide a desired coverage pattern with a desired SPL.

Claims

1. A sound source system for directing sound, comprising:

a first plurality of sound sources arranged in a first plane, the plurality of sound sources having a first sound source and a second sound source, where the first sound sources lies in a reference plane that is normal to a vector along a central axis of a main sound lobe; and

an audio signal source coupled to a delay element that delays an audio signal to the second sound source by an amount proportional to a delay distance, where the delay distance is a distance between the first sound source and a point of intersection between a first line and a second line, where the first line passes through the first sound source perpendicular to the reference plane, and the second line passes through the second sound source perpendicular to the first line.

2. The sound source system according to claim 1, further including an amplifier for amplifying the audio signal to the sound sources.

3. The sound source system according to claim 1, further comprising a second plurality of sound sources arranged in a second plane, where the first and second planes are aligned along a reference axis, where the vector is capable of aiming up to 360°

from the reference axis.

4. The sound source system according to claim 1, where the main sound lobe has a width angle and a height angle of about 90°

.

5. A sound source system for directing sound, comprising:

a first array of sound sources arranged in a first plane, where each sound source is positioned relative to a reference plane, where the array includes a first sound source located in a reference plane, and a second sound source, where the reference plane is substantially normal to a vector along a central axis of a main sound lobe generated from the first array of sound sources, and where second sound source is coupled to a delay element that delays an audio signal to the second sound source by an amount proportional to a delay distance, where the delay distance is a distance between the first sound source and a point of intersection between a first line and a second line, where the first line passes through the first sound source pendicular to the reference plane, and the second line passes through the second sound source perpendicular to the first line.

6. The sound source system according to claim 5, further comprising a second array of sound sources arranged in a second plane, where the vector for the main sound lobe is positioned between the first plane and the second plane.

7. The sound source system according to claim 5, where the first plane is coupled to the second plane.

8. The sound source according to claim 7, where the first and second planes are aligned along a reference axis, where the vector is capable of aiming up to 360°

from the reference axis.

9. The sound source according to claim 7, where the main sound lobe has a width angle and a height angle of about 90°

.

10. The sound source system according to claim 5, where the main sound lobe has a lobe height, a lobe width, and a lobe depth, and each array of sound sources has a corresponding array height, array width, and array depth, where adding more sound sources to at least one of the arrays of sound sources along the corresponding array width reduces the lobe height;

and where adding more sound sources to the at least one array of sound sources along the corresponding array depth adds power to the main sound lobe and increases an off-axis rejection.

11. The sound source system according to claim 5, where the delay element delays the audio signal based on a time it takes for wave fronts to travel the delay distance.

12. The sound source system according to claim 6, where the sound sources in the first plane are symmetrical to the sound sources in the second plane, respectively.

13. The sound source system according to claim 12, where third sound source is positioned in the second plane, and where the second and third sound sources are both coupled to the delay element.

14. The sound source system according to claim 6, where the arrays of sound sources are assembled from dual sound source elements, where each of the dual sound source elements has a cavity between two sound sources that are mounted on a base, where electromagnetic motors for each of the two sound sources face away from each other.

15. The sound source system according to claim 14, where the bases for each dual sound source elemcnt are adapted to be assembled together to form columns and rows of the dual sound elements.

16. The sound source system according to claim 14, where each of the two sound sources for each dual sound source element has a cone having a diameter between about 4 inches (101.6 mm) and about 36 inches (914.4 mm).

17. The sound source system according to claim 14, where each of the two sound sources for each dual sound source element has a cone having a diameter of about 12 inches (3.048 mm).

18. The sound source system according to claim 17, where outer ends of the cones of the two sound sources are spaced about 0.2 to 0.3 times a predetermined operating frequency wavelength.

19. The sound source system according to claim 17, where outer ends of the cones of the two sound sources are spaced at least about 0.2 times a predetermined operating frequency wavelength.

20. The sound source system according to claim 17, where outer ends of the cones of the two sound sources are spaced less than about 0.3 times a predetermined operating frequency wavelength.

21. The sound source system according to claim 14, where each of the dual sound source elements operates between about 50 Hz and about 250 Hz frequency range.

22. The sound source system according to claim 6, where the arrays of sound sources are assembled from dual sound source elements, where each of the sound source elements includes two sound sources mounted into a base so as to form a first cavity between the base and a first of the two sound sources, and a second cavity between the base and a second of the two sound sources, where a divider wall separates the first cavity and the second cavity, and electromagnetic motors for each of the two sound sources face out.

23. The sound source system according to claim 22, where the bases for each of the sound source elements are adapted to be assembled together.

24. The sound system according to claim 23, where the first plane the second plane are arranged with a space between the first and second planes, and where electromagnetic motors of the sound sources in the first plane face electromagnetic motors of the sound sources in the second plane.

25. The sound source system according to claim 24, where a truss member is used to couple the first array of sound sources and the second array of sound sources.

26. The sound source system according to claim 23, where each of the two sound sources for each sound source element have a cone diameter between about 4 inched (101.6 mm) and about 36 inches (914.4 mm).

27. The sound source system according to claim 22, where each of the two sound sources for each sound source element has a cone having a diameter of about 15 inches (381 mm).

28. The sound source system according to claim 22, where the sound source elements operated between about 50 Hz and about 250 Hz frequency range.

29. The sound source system according to claim 22, where the arrays of sound sources are assembled from dual sound source elements, where each dual sound source element includes two sound sources housed in a box having a port.

30. The sound source system according to claim 29, where each box has a trapezoidal side cross-section, where the boxes are stacked together to from the first and second planes of sound sources, and where the sound sources in the first plane are offset relative to the sound sources in the second plane.

31. The sound source system according to claim 29, where each of the sound sources has a cone having a diameter of between about 4 inches (101.6 mm) and about 36 inches (914.4 mm).

32. The sound source system according to claim 29, where each of the sound sources has a cone having a diameter of about 18 inches (457.2 mm).

33. The sound source system according to claim 29, where each of the sound sources operate between about 25 Hz and about 125 Hz frequency range.

34. The sound source system according to claim 6, where the first plane forms an angle relative to the second plane, where the first and second planes are closer to each other at a first end than at a second end, and where sound sources positioned near the first end are driven with a higher frequency audio signal than the sounds sources positioned near the second end.

35. A sound source system, comprising:

at least one sound source element having a pair of sound sources, each sound source including a cone and an electromagnetic motor, where the pair of sound sources, comprising a first sound source and a second sound source, is positioned within a base such that a cavity is formed between the respective cones and the respective electromagnetic motors face outward, and where the base is configured to stack multiple sound source elements into columns and rows, such that each sound source is positioned relative to a reference plane that is substantially normal to a vector along a central axis of a main sound lobe, where the first sound source lies in the reference plane, and the second sound source is coupled to a delay element that delays an audio signal to the second sound source by an amount proportional to a delay distance, where the delay distance is a distance between a point of intersection between a first line and a second line, where the first line passes through the first sound source perpendicular to the reference plane, and the second line passes through the second sound source perpendicular to the first line.

36. A method for directing sound, comprising:

grouping a first plurality of sound sources into a first plane, where the plurality of sound sources includes a first sound source and a second sound sources, where each sound source in the plurality of sound sources is positioned relative to a reference plane that is substantially normal to a vector along a central axis of a main sound lobe generated from the sound sources, and where a first sound source lies in the reference plane; and

delaying an audio signal to at least one sound source by an amount proportional to a delay distance, where the delay distance is a distance between first sound source and a point of intersection between a first line and a second line, where the first line passes through the first sound source perpendicular to the reference plane. and the second line passes through the second sound source perpendicular to the first line.

37. The method according to claim 36, further including amplifying the audio signal to each sound source.

38. The method according to claim 36, further comprising:

grouping a second plurality of sound sources into a second plane;

positioning the sound sources in the first plane symmetrically relative to the sound sources in the second plane; and

delaying the audio signal to the first sound source in the first plane and a third sound source in the second plane via one delay element, where the first sound source and the third sound have substantially the same delay distance.

39. The method according to claim 36, further including stacking the sound sources so that the sound sources in the first are offset relative to the sound sources in the second plane.

40. The method according to the claim 39, further including stacking the sound sources to form an array having columns and rows of sound sources, where eletromagnetic motors for each of the sound sources in the first and second planes face out.

41. The method according to claim 39, furthering including:

assembling the sound sources to form a first array and a second atray, where electromagnetic motors for the sound sources in the first and second arrays face out, and where the first array defines the first plane and the second array defines the second plane;

spacing the first and second arrays to control a width of the main sound lobe; and

coupling the first and second arrays so that the magnetic motors from the sound sources in the first array face the magnetic motors from the sound sources in the second array.

42. The method according to claim 39, further including spacing the first plane from the second plane to control a width of the main sound lobe.

43. The method according to claim 39, further including positioning the first and second planes substantially parallel to each other.

44. The method according to claim 36, further including frequency shading the audio signal to provide the main sound lobe with consistent coverage vertically along most operating frequencies.

45. A method for directing sound, comprising:

defining a vector along a central axis of a main sound lobe and a reference plane that is normal to the vector;

grouping a first plurality of sound sources into a first plane, where said first plurality of sound sources includes a first sound source that lies in the reference plane, and a second sound source;

coupling a common signal source to each sound source; and

delaying an audio signal to at the second sound source by an amount proportional to a delay distance, where the delay distance is a distance between the at first sound source and a point of intersection between a first line and a second line, where the first line passes through the first sound source perpendicular to the reference plane, and the second line passes through the second sound source perpendicular to the first line.