DIRECTIONAL LOUDSPEAKER TO REDUCE DIRECT SOUND

• US 20080247575A1
• Filed: 04/05/2007
• Published: 10/09/2008
• Est. Priority Date: 04/05/2007
• Status: Active Grant

• Current Assignee: Harman International Industries Incorporated (Samsung Electronics Co. Ltd.)
• Original Assignee: Harman International Industries Incorporated (Samsung Electronics Co. Ltd.)
• Inventors: Hutt, Steven W., House, William Neal, Armitage, Mark Justin, Mihelich, Ryan
• Granted Patent: US 8,121,336 B2
• Time in Patent Office: Days
• US Class Current: 381/302
• CPC Class Codes: H04R 1/025 Arrangements for fixing loudspeaker transducers, e.g. in a box, furniture
• CPC Class Codes: H04R 1/345 for loudspeakers
• CPC Class Codes: H04R 2201/021 Transducers or their casings adapted for mounting in or to a wall or ceiling
• CPC Class Codes: H04R 5/02 Spatial or constructional arrangements of loudspeakers

Abstract

A directional loudspeaker provides an enhanced listening environment by producing an indirect sound field of greater amplitude than that of the direct sound field. The directional loudspeaker includes loudspeaker elements positioned to provide a listener located below the loudspeaker elements with an impression of sound spaciousness in a vehicle environment. The loudspeaker elements may include baffles or acoustic lenses to deflect the indirect field away from the path to the listener position. The loudspeaker may also be operated with windows open by channeling the indirect sound field through an acoustic waveguide and deflector to the listener. A sound processor is also provided to accept a sound input, create an indirect and direct sound field, output the sound fields to loudspeaker elements, and also may provide electronic enhancement effects such as multi-channel sound or sound parameter adjustment.

Claims

1. A loudspeaker system for placement in an at least partially enclosed space, the at least partially enclosed space having boundary walls and at least one listener position comprising a loudspeaker element adaptable to be positioned within the space so that the loudspeaker element is operable to produce a greater indirect sound field than a direct sound field at the at least one listener position, and so that the indirect sound field is reflected by at least one surface of the at least partially enclosed space before reaching the at least one listener position, where the loudspeaker element is further positionable integral with one of the boundary walls proximate the at least one listener position, and where the loudspeaker element includes a baffle positioned between the loudspeaker element and the at least one listener position to deflect the indirect sound field from a direction away from the loudspeaker element.

2. The loudspeaker system of claim 1, where the direct sound field is propagated substantially parallel to a straight line between the at least one listener position and the loudspeaker element.

3. The loudspeaker system of claim 2, where the loudspeaker element comprises a dipole loudspeaker.

4. The loudspeaker system of claim 2, where the loudspeaker element comprises a radiating surface, and where the baffle is proximate to the radiating surface of the loudspeaker element.

5. The loudspeaker system of claim 4, where the baffle abuts the radiating surface of the loudspeaker element.

6. The loudspeaker system of claim 3, where the loudspeaker element comprises an electrodynamic planar loudspeaker.

7. The loudspeaker system of claim 1, where the loudspeaker element comprises a first loudspeaker element and a second loudspeaker element, and where a path length of the direct sound field from the first loudspeaker element to the at least one listener position is substantially equal to a path length of the indirect sound field from the second loudspeaker element to the at least one listener position.

8. The loudspeaker system of claim 1, where the at least partially enclosed space comprises a vehicle separated into a front compartment and a rear compartment,

where the front compartment comprises a driver area and a front passenger area, and the rear compartment comprises an area rearward of the front compartment, and

where the first loudspeaker element is positioned in the front compartment, and the second loudspeaker element is positioned in the rear compartment.

9. The loudspeaker system of claim 8, where at least one of the loudspeaker elements has a baffle positioned beneath the loudspeaker element operable to deflect the indirect sound field away from a direction directly below the loudspeaker element.

10. The loudspeaker system of claim 2, where the loudspeaker element comprises a loudspeaker, an acoustic deflector, and an acoustic waveguide coupling the loudspeaker and the deflector, and

where the loudspeaker element is positionable at a first end of the acoustic waveguide and the deflector is positionable at a second end of the acoustic waveguide.

11. The loudspeaker system of claim 10, where one of the boundary walls of the at least partially enclosed space comprises a ceiling, and

where the acoustic waveguide is positionable along the ceiling of the at least partially enclosed space.

12. The loudspeaker system of claim 11, where the deflector abuts an intersection of the ceiling and a boundary wall of the at least partially enclosed space.

13. The loudspeaker system of claim 10, where at least one of the boundary walls comprises an opening to an outside environment.

14. The loudspeaker system of claim 10, where the at least partially enclosed space comprises a vehicle separated into a front compartment and a rear compartment,

where the front compartment comprises a driver area and a front passenger area, and the rear compartment comprises an area rearward of the front compartment, and

where at least one of the loudspeaker elements is positionable in the front compartment, and at least one of the loudspeaker elements is positionable in the rear compartment.

15. The loudspeaker system of claim 14, where the loudspeaker element is positionable in the rear compartment comprises a dipole loudspeaker.

16. The loudspeaker system of claim 1, where the loudspeaker is adapted for use in an automobile.

17. The loudspeaker system of claim 16, where the loudspeaker system is adapted to operate with an automobile audio system to adjust a phase, gain, or delay parameter of at least one of the direct field or the indirect sound field for electronic enhancement.

18. The loudspeaker system of claim 10, where the loudspeaker system is adapted for use in an automobile.

19. The loudspeaker system of claim 18, where the loudspeaker system is adapted to operate with an automobile audio system to adjust a phase, gain, or delay parameter of at least one of the direct field or the indirect sound field for electronic enhancement.

30. The loudspeaker system of claim 1, where the loudspeaker system is configured for use in a home theater environment.

31. The loudspeaker system of claim 1, where the at least partially enclosed space comprises a vehicle separated into a front compartment and a rear compartment,

where the front compartment comprises a driver area and a front passenger area, and the rear compartment comprises an area rearward of the front compartment, and

where at least one loudspeaker elements is positionable in the rear compartment.

32. The loudspeaker system of claim 31, where the loudspeaker element comprises a baffle, where the baffle is positionable between the loudspeaker element and the listener position.

33. The loudspeaker system of claim 32, where the loudspeaker element comprises a radiating surface, and where the baffle is proximate to the radiating surface of the loudspeaker element.

34. The loudspeaker system of claim 33, where the baffle abuts the radiating surface of the loudspeaker element.

41. The loudspeaker system of claim 1, where the loudspeaker element is pivotably mounted to the boundary.

42. The loudspeaker system of claim 1, where the loudspeaker element is positionable in a headliner of a vehicle.

51. The loudspeaker system of claim 42, where the loudspeaker element is positionable approximately less than two feet from the listener position.

20. A loudspeaker system for placement in an at least partially enclosed space, the space having boundary walls and at least one listener position comprising:

a loudspeaker element mountably positionable along a boundary wall above a listener position; and

means for producing an indirect sound field greater than a direct sound field at the listener position, where the indirect sound field is reflected by at least surface of the at least partially enclosed space before reaching the listener position.

21. The loudspeaker system of claim 20, where the means for producing an indirect sound field greater than a direct sound field at the listener position comprises means for deflecting the indirect sound field away from a straight line between the loudspeaker element and the listener position.

22. The loudspeaker system of claim 21, where the means for deflecting the indirect sound field is positionable between the loudspeaker element and the listener position.

23. The loudspeaker system of claim 22, where the loudspeaker element comprises at least one radiating surface indicating a direction of a sound field produced by the loudspeaker element, and where the means for deflecting the indirect sound field abuts the radiating surface of the loudspeaker element.

24. The loudspeaker system of claim 20, where the loudspeaker element comprises a dipole loudspeaker.

25. The loudspeaker system of claim 24, where the dipole loudspeaker comprises an electrodynamic planar loudspeaker.

26. The loudspeaker system of claim 20, where the at least partially enclosed space comprises a vehicle separated into a front compartment and a rear compartment,

where the front compartment is a driver area and a front passenger area, and the rear compartment is an area rearward of the front compartment, and

where at least one loudspeaker element is positionable in the front compartment, and at least one loudspeaker element is positionable in the rear compartment.

27. A method that enhances the audio environment of a listener in an at least partially enclosed space having boundary walls, and also having a ceiling, and a listener position comprising:

mountably positioning a loudspeaker element along a boundary wall above a listener position;

producing an indirect sound field by the loudspeaker element; and

producing a direct sound field by the loudspeaker element,

where the indirect sound field is reflected by at least one surface of the at least partially enclosed space before reaching the listener position, and

where the indirect sound field is greater than the direct sound field at at least one listener position.

28. The method of claim 27, where the direct sound field is greater than the indirect sound field at another listener position.

29. The method of claim 27, further comprising adjusting a phase, gain, or delay parameter of at least one of the indirect sound field or the direct sound field for electronic enhancement.

35. A sound processor that generates an acoustically enhanced environment comprising:

an input unit operable to receive an input sound source;

a sound processor operable to generate an indirect sound field and a direct sound field from the input sound source; and

an output unit operable to output an output sound source,

where the indirect sound field is reflected by at least one surface of an at least partially enclosed space, and

where the indirect sound field is greater than the direct sound field at a listener position.

36. The sound processor of claim 35, further comprising a memory operable to store one or more parameters that generate the indirect sound field and direct sound field.

37. The sound processor of claim 36, where the sound processor is operable to adjust a phase, gain, or delay parameter of at least one of the indirect sound field or the direct sound field for electronic enhancement.

38. The sound processor of claim 37, where the memory stores one or more of the phase, gain, or delay parameters.

39. The sound processor of claim 38, where the output unit is operable to generate more than one channel of a sound output.

40. A loudspeaker system for placement in an at least partially enclosed space, the space having boundary walls and a listener position comprising:

a first loudspeaker element adapted to be positioned within the at least partially enclosed space so that the loudspeaker element is operable to produce a greater first indirect sound field than a first direct sound field at the listener position, and so that the indirect sound field is reflected by at least one surface of the at least partially enclosed space, where the loudspeaker element is further positionable integral with the boundary wall proximate the listener position;

a second loudspeaker element positionable within the space and operable to produce a second direct sound field; and

a virtual loudspeaker source perceivable by the listener as originating from a position different from the first loudspeaker element position and the second loudspeaker element position,

where the second direct sound field and the first indirect sound field are combinable to produce the virtual loudspeaker source.

43. A loudspeaker system for placement in an at least partially enclosed space, the space having boundary walls and a listener position comprising a loudspeaker element adapted to be positioned within the space so that the loudspeaker element is operable to produce a greater indirect sound field than a direct sound field at the listener position, and so that the indirect sound field is reflected by at least one surface of the at least partially enclosed space, where the loudspeaker element is further positionable integral with the boundary wall proximate a listener position, where the loudspeaker element comprises a loudspeaker, an acoustic deflector, and an acoustic waveguide coupling the loudspeaker and the deflector, and

where the loudspeaker element is positioned at a first end of the acoustic waveguide and the deflector is positioned at a second end of the acoustic waveguide.

44. The loudspeaker system of claim 43, where one of the boundary walls of the at least partially enclosed space comprises a ceiling and a headliner, and where the acoustic waveguide is positionable along the ceiling integral with the headliner.

45. A loudspeaker system comprising:

at least one loudspeaker element; and

a channeling device acoustically coupled to the loudspeaker element, where the channeling device is operable to produce a greater indirect sound field than a direct sound field at a listener position.

46. The loudspeaker system of claim 45, where the channeling device comprises a baffle positionable between the loudspeaker element and the listener position to deflect the indirect sound field from a direction directly below the loudspeaker element.

47. The loudspeaker system of claim 46, where the loudspeaker element comprises a radiating surface, and

where the baffle is proximate to the radiating surface of the loudspeaker element.

48. The loudspeaker system of claim 47, where the baffle abuts the radiating surface of the loudspeaker element.

49. The loudspeaker system of claim 45, where the channeling device comprises an acoustic deflector and an acoustic waveguide coupling the loudspeaker and the deflector, and

where the loudspeaker element is positionable at a first end of the acoustic waveguide and the deflector is positionable at a second end of the acoustic waveguide.

50. The loudspeaker system of claim 47, where the channeling device further comprises:

an acoustic lens positionable proximate the radiating surface of the loudspeaker element and the baffle, where the acoustic lens is further positionable between the radiating surface of the loudspeaker element and the baffle.