Loudspeaker array protection management

• US 9,743,201 B1
• Filed: 03/13/2014
• Issued: 08/22/2017
• Est. Priority Date: 03/14/2013
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Lindahl, Aram M., Button, Douglas J.
• Primary Examiner(s): Gauthier, Gerald
• Application Number:
  US14/210,100
• Time in Patent Office: 1,258 Days
• Field of Search: 3406913, 341 53, 370389, 381 17, 381 55, 381 59, 381 61, 381 711, 381 89, 381103, 381119, 381304, 381345, 381186, 381303, 381387, 381 77, 381 92, 381111, 381160, 381300, 381301, 381306, 381307, 381340, 381342, 381396, 381431, 381386, 381 98, 381182, 381339, 381107, 367138, 367 13, 367153, 367 87, 73584, 73632, 600443, 607 45, 601 2, 473101
• CPC Class Codes: H04R 29/002 Loudspeaker arrays
• CPC Class Codes: H04R 3/04 for correcting frequency response
• CPC Class Codes: H04R 3/12 for distributing signals to two or more loudspeakers specially adapted for hearing aids H04R25/407

Abstract

A protection management unit is described that detects one or more poor performing transducers in a loudspeaker array. Upon detection of one or more poor performing transducers, the protection management unit adjusts driving signals for neighboring transducers to compensate for the reduced capabilities of the poor performing transducers. By adjusting driving signals to neighboring transducers, the protection management unit ensures that a desired tone and spatial response for sound emitted by the loudspeaker array is maintained despite one or more poor performing transducers. Other embodiments are also described.

Claims

1. A method by an audio receiver for compensating for poor performing transducers in a loudspeaker array, the audio receiver having one or more inputs, the method comprising:

receiving at each input one or more source audio signals representing one or more channels of a piece of sound program content;

monitoring by a protection management unit each transducer in the loudspeaker array to determine an inoperative transducer while the transducers are driven based on the audio signals; and

altering by a main system processor driving signals applied to transducers neighboring the inoperative transducer to compensate for a lack of output from the inoperative transducer.

2. The method of claim 1, wherein monitoring each transducer in the loudspeaker array, comprises:

modeling each transducer based on current and voltages sent from power amplifiers associated with each transducer; and

comparing the current and voltages of driving signals sent from the power amplifiers to each transducer with the modeled current and voltages sent from power amplifiers associated with each transducer to determine the inoperative transducer.

3. The method of claim 1, further comprising:

altering driving signals applied to the inoperative transducer to reduce potential damage to the inoperative transducer.

4. The method of claim 3, wherein altering the driving signals applied to the inoperative transducer, comprises:

high-pass filtering the driving signals applied to the inoperative transducer to remove low-frequency content below a cutoff frequency.

5. The method of claim 4, wherein altering the driving signals applied to the neighboring transducers to compensate for the lack of output from the inoperative transducer, comprises:

increasing low-frequency content in the driving signals applied to the neighboring transducers.

6. The method of claim 4, wherein altering the driving signals applied to the neighboring transducers to compensate for the lack of output from the inoperative transducer, comprises:

increasing the energy level of one or more frequency bands in the driving signals applied to the neighboring transducers.

7. The method of claim 1, wherein the neighboring transducers are transducers immediately adjacent to the inoperative transducer in the loudspeaker array.

8. A computing device for compensating for poor performing transducers in a loudspeaker array, comprising:

one or more inputs for receiving one or more source audio signals representing one or more channels of a piece of sound program content;

a hardware processor; and

a memory unit for storing instructions, which when executed by the hardware processor;

monitor each transducer in the loudspeaker array to determine a poor performing transducer by examining the current and voltages of driving signals sent from power amplifiers to each transducer while the transducers are driven based on the audio signals, and

alter the driving signals applied to transducers neighboring the poor performing transducer to compensate for a reduced performance level of the poor performing transducer.

9. The computing device of claim 8, wherein the poor performing transducer is a transducer in the loudspeaker array that is operating below a prescribed tolerance.

10. The computing device of claim 8, wherein the memory unit includes further instructions, which when executed by the hardware processor:

model each transducer based on current and voltages sent from power amplifiers associated with each transducer; and

compare the current and voltages of driving signals sent from the power amplifiers to each transducer with the modeled current and voltages sent from power amplifiers associated with each transducer to determine the poor performing transducer.

11. The computing device of claim 8, wherein the memory unit includes further instructions, which when executed by the hardware processor:

alter driving signals applied to the poor performing transducer to reduce potential damage to the poor performing transducer.

12. The computing device of claim 11, wherein the memory unit includes further instructions, which when executed by the hardware processor:

high-pass filter the driving signals applied to the poor performing transducer to remove low-frequency content below a cutoff frequency.

13. The computing device of claim 12, wherein the memory unit includes further instructions, which when executed by the hardware processor:

increase low-frequency content in the driving signals applied to the neighboring transducers to compensate for the low-frequency content removed from the driving signals applied to the poor performing transducer.

14. The computing device of claim 13, wherein the memory unit includes further instructions, which when executed by the hardware processor:

increase the energy level of one or more frequency bands in the driving signals applied to the neighboring transducers to compensate for the low-frequency content removed from the driving signals applied to the poor performing transducer.

15. The computing device of claim 8, wherein the neighboring transducers are transducers immediately adjacent to the poor performing transducer in the loudspeaker array.

16. An article of manufacture for compensating for poor performing transducers in a loudspeaker array, comprising:

a non-transitory machine-readable storage medium that stores instructions which, when executed by a processor in a computer,

monitor each transducer in the loudspeaker array to determine a an inoperative transducer, and

alter driving signals applied to transducers neighboring the inoperative transducer to compensate for a lack of output from the inoperative transducer.

17. The article of manufacture of claim 16, wherein the non-transitory machine-readable storage medium stores further instructions which, when executed by the processor:

model each transducer based on current and voltages sent from power amplifiers associated with each transducer; and

compare the current and voltages of driving signals sent from the power amplifiers to each transducer with the modeled current and voltages sent from power amplifiers associated with each transducer to determine the inoperative transducer.

18. The article of manufacture of claim 16, wherein the non-transitory machine-readable storage medium stores further instructions which, when executed by the processor:

alter driving signals applied to the inoperative transducer to reduce potential damage to the inoperative transducer.

19. The article of manufacture of claim 18, wherein the non-transitory machine-readable storage medium stores further instructions which, when executed by the processor:

high-pass filter the driving signals applied to the inoperative transducer to remove low-frequency content below a cutoff frequency.

20. The article of manufacture of claim 19, wherein the non-transitory machine-readable storage medium stores further instructions which, when executed by the processor:

increase low-frequency content in the driving signals applied to the neighboring transducers.

21. The article of manufacture of claim 19, wherein the non-transitory machine-readable storage medium stores further instructions which, when executed by the processor:

increase the energy level of one or more frequency bands in the driving signals applied to the neighboring transducers.

22. The article of manufacture of claim 16, wherein the neighboring transducers are transducers immediately adjacent to the inoperative transducer in the loudspeaker array.

23. A method for adjusting audio emitted by a speaker array, comprising:

playing audio content through a plurality of transducers in the speaker array to produce a desired tone and spatial response;

detecting a transducer in the speaker array performing below a predefined threshold;

reducing frequency content applied to the detected transducer;

compensating for the detected transducer by adjusting frequency content applied to the remaining transducers in the speaker array to maintain the desired tone and spatial response for the audio content.

24. The method as in claim 23 wherein the frequency content is reduced to prevent potential damage to the detected transducer.

25. The method as in claim 23 wherein the remaining transducers are adjacent to the detected transducer and wherein the compensating comprises increasing the energy level of one or more frequency bands in the driving signals applied to the remaining transducers.

26. The method as in claim 25 wherein the detecting comprises comparing current or voltage of driving signals sent from one or more power amplifiers to each transducer with modelled current or voltage sent from one or more amplifiers.

27. A receiver apparatus comprising:

a processing system;

one or more amplifiers coupled to the processing system, the one or more amplifiers having outputs, each of which is coupled to a transducer in a speaker array, the processing system configured to play audio content through a plurality of transducers in the speaker array to produce a desired tone and spatial response, and to detect a poor performing transducer in the speaker array performing below a predefined threshold and to reduce content in a frequency band applied to the poor performing transducer that is performing below the predefined threshold and to compensate for the reduction by adjusting content in the frequency band applied to the remaining transducers in the speaker array to maintain the desired tone and spatial response for the audio content.

28. The receiver as in claim 27 wherein the content is reduced to prevent potential damage to the poor performing transducer.

29. The receiver as in claim 27 wherein the processing system detects the poor performing transducer by comparing current or voltage applied to the poor performing transducer to modelled current or voltage.

30. A receiver apparatus comprising:

a processing system;

a set of amplifiers coupled to the processing system, the set of amplifiers having outputs, each of which is coupled to a transducer in a speaker array, the processing system configured to play audio content through a plurality of transducers in the speaker array to produce a desired tone and spatial response, and to detect a poor performing transducer in the speaker array performing below a predefined threshold and to reduce content in a frequency band applied to the poor performing transducer that is performing below the predefined threshold and to compensate for the reduction by adjusting content in the frequency band applied to the remaining transducers in the speaker array to maintain the desired tone and spatial response for the audio content.

31. The receiver as in claim 30 wherein the content is reduced to prevent potential damage to the poor performing transducer.

32. The receiver as in claim 30 wherein the processing system detects the poor performing transducer by comparing current or voltage applied to the poor performing transducer to modelled current or voltage.

33. The receiver as in claim 30 wherein each transducer in the speaker array is individually and separately driven by one amplifier in the set of amplifiers.

34. The receiver as in claim 30 wherein the remaining transducers are adjacent to the poor performing transducer.

35. The receiver as in claim 33 wherein the receiver comprises one or more inputs for receiving sound program content using electrical, radio or optical signals from an external device.

36. The receiver as in claim 35 wherein the one or more inputs include a wireless adapter for communicating with an external device using wireless protocols.

37. A receiver apparatus comprising:

a processing system;

one or more amplifiers coupled to the processing system, the one or more amplifiers having outputs, each of which is configured to drive a transducer in a speaker array, the processing system configured to play audio content through a plurality of transducers in the speaker array to produce a desired tone and spatial response, and to detect a poor performing transducer in the speaker array performing below a predefined threshold and to reduce content in a frequency band applied to the poor performing transducer that is performing below the predefined threshold and to compensate for the reduction by adjusting content in the frequency band applied to the remaining transducers in the speaker array to maintain the desired tone and spatial response for the audio content.

38. The receiver as in claim 37 wherein the content is reduced to prevent potential damage to the poor performing transducer.

39. The receiver as in claim 37 wherein the processing system detects the poor performing transducer by comparing current or voltage applied to the poor performing transducer to modelled current or voltage.

40. The receiver as in claim 37 wherein each transducer in the speaker array is individually and separately driven by one amplifier in the one or more amplifiers.

41. The receiver as in claim 37 wherein the remaining transducers are adjacent to the poor performing transducer.

42. The receiver as in claim 37 wherein the receiver comprises one or more inputs for receiving sound program content using electrical, radio or optical signals from an external device.

43. The receiver as in claim 42 wherein the one or more inputs include a wireless adapter for communicating with an external device using wireless protocols.

44. A receiver apparatus comprising:

a processing system;

one or more amplifiers coupled to the processing system, the one or more amplifiers having outputs, each of which is configured to drive a transducer in a speaker array, the processing system configured to play audio content through a plurality of transducers in the speaker array to produce a desired tone and spatial response, and to detect a poor performing transducer in the speaker array performing below a predefined threshold and to adjust driving signals applied to the poor performing transducer that is performing below the predefined threshold and to compensate for the adjustment by adjusting driving signals applied to the one or more remaining transducers in the speaker array to compensate for the poor performing transducer.

45. The receiver as in claim 44 wherein the driving signal is adjusted to prevent potential damage to the poor performing transducer.

46. The receiver as in claim 44 wherein the processing system detects the poor performing transducer by comparing current or voltage applied to the poor performing transducer to modelled current or voltage.

47. The receiver as in claim 44 wherein each transducer in the speaker array is individually and separately driven by one amplifier in the one or more amplifiers.

48. The receiver as in claim 44 wherein the one or more remaining transducers are adjacent to the poor performing transducer.

49. The receiver as in claim 44 wherein the receiver comprises one or more inputs for receiving sound program content using electrical, radio or optical signals from an external device.

50. The receiver as in claim 49 wherein the one or more inputs include a wireless adapter for communicating with an external device using wireless protocols.