Passive directional acoustic radiating

• US 8,447,055 B2
• Filed: 08/12/2010
• Issued: 05/21/2013
• Est. Priority Date: 05/02/2008
• Status: Expired

• Current Assignee: Bose Corporation
• Original Assignee: Bose Corporation
• Inventors: Jankovsky, Joseph, Johanson, Eric S., Saffran, Richard
• Primary Examiner(s): Goins, Davetta W
• Assistant Examiner(s): ETESAM, AMIR HOSSEIN
• Application Number:
  US12/854,982
• Publication Number:
  US 20110026744A1
• Time in Patent Office: 1,013 Days
• Field of Search: 381/337, 381/388, 381/338, 381/339
• US Class Current: 381/337
• CPC Class Codes: G10K 11/26 Sound-focusing or directing, e.g. scanning
• CPC Class Codes: H04R 1/2819 for loudspeaker transducers
• CPC Class Codes: H04R 1/345 for loudspeakers

Abstract

An audio system for a television using a pipe type passive directional acoustic device mounted in a television cabinet. The slotted pipe type passive directional acoustic device includes a first acoustic driver, acoustically coupled to a pipe to radiate acoustic energy into the pipe. The first pipe includes an elongated opening along at least a portion of the length of the pipe. Acoustically resistive material is in the opening. Pressure waves are radiated to the environment through the opening. The pressure waves are characterized by a volume velocity. The pipe, the opening, and the acoustically resistive material are configured so that the volume velocity is substantially constant along the length of the pipe. The passive directional acoustic devices directionally radiate sound waves laterally from the television cabinet.

Claims

1. An audio system for a television comprising:

a television cabinet;

a first slotted pipe type passive directional acoustic device comprising

a first acoustic driver, acoustically coupled to a pipe to radiate acoustic energy into the pipe,

the first pipe comprising

an elongated opening along at least a portion of the length of the pipe; and

acoustically resistive material in the opening through which pressure waves are radiated to the environment,

the pressure waves characterized by a volume velocity, the pipe, the opening, and the acoustically resistive material configured so that the volume velocity of the pressure waves radiated to the environment from the pipe is substantially constant along the length of the pipe; and

wherein the passive directional acoustic device is mounted in the television cabinet to directionally radiate sound waves laterally from the television cabinet.

2. The audio system for a television of claim 1, wherein the pipe is at least one of bent or curved.

3. The audio system for a television of claim 2 wherein the opening is at least one of bent or curved along its length.

4. The slotted pipe type passive directional acoustic device of claim 2, wherein the opening is in a face that is bent or curved.

5. The audio system for a television of claim 2, wherein the television cabinet is tapered backwardly, and wherein the passive directional acoustic device is mounted so that a curved or bent wall of the slotted pipe type passive directional acoustic device is substantially parallel to the back and a side wall of the television cabinet.

6. The audio system for a television of claim 2, wherein the opening comprises two sections, a first section in a top face of the pipe and a second section in a side face of the pipe.

7. The audio system for a television of claim 1, wherein the passive directional acoustic device is for radiating the high frequency content of a left channel or a right channel laterally from the television.

8. The audio system for a television of claim 7, wherein the acoustic device is for radiating the left channel or right channel content above 2 kHz.

9. The audio system for a television of claim 7, further comprising a directional array for radiating midrange frequency content of the left channel or right channel laterally from the television.

10. The audio system for a television of claim 9, further comprising a waveguide structure for radiating bass frequency content of

the left channel or right channel;

the other of the left channel or right channel; and

a center channel.

11. The audio system of claim 1, wherein the cross sectional area of the pipe decreases along the length of the pipe.

12. The audio system of claim 1, further comprising a second slotted pipe type passive directional acoustic device comprising

a second acoustic driver, acoustically coupled to a pipe to radiate acoustic energy into the pipe,

the second pipe comprising

an elongated opening along at least a portion of the length of the pipe;

and

acoustically resistive material in the opening through which pressure waves are radiated to the environment,

the pressure waves characterized by a volume velocity, the pipe, the opening, and the acoustically resistive material configured so that the volume velocity is substantially constant along the length of the pipe; and

wherein the first passive directional acoustic device is mounted in the television cabinet to directionally radiate sound waves laterally leftward from the television cabinet and the second passive radiator is mounted in the television cabinet to directionally radiate sound waves laterally rightward from the television cabinet.