System for selecting correction factors for an audio system

• US 20050031130A1
• Filed: 10/10/2003
• Published: 02/10/2005
• Est. Priority Date: 08/04/2003
• Status: Active Grant

• Current Assignee: Harman International Industries Incorporated (Samsung Electronics Co. Ltd.)
• Original Assignee: Harman International Industries Incorporated (Samsung Electronics Co. Ltd.)
• Inventors: Devantier, Allan O., Welti, Todd S.
• Granted Patent: US 8,755,542 B2
• Time in Patent Office: Days
• US Class Current: 381/58
• CPC Class Codes: H04R 2205/024 Positioning of loudspeaker enclosures for spatial sound reproduction
• CPC Class Codes: H04R 2420/03 Connection circuits to selectively connect loudspeakers or headphones to amplifiers
• CPC Class Codes: H04R 5/04 Circuit arrangements, e.g. for selective connection of amplifier inputs/outputs to loudspeakers, for loudspeaker detection, or for adaptation of settings to personal preferences or hearing impairments combinations of amplifiers H03F3/68; stereophonic systems H04S
• 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

A system is provided for configuring an audio system for a given space. The system may statistically analyze potential configurations of the audio system to configure the audio system. The potential configurations may include positions of the loudspeakers, numbers of loudspeakers, types of loudspeakers, listening positions, correction factors, or any combination thereof. The statistical analysis may indicate at least one metric of the potential configuration including indicating consistency of predicted transfer functions, flatness of the predicted transfer functions, differences in overall sound pressure level from seat to seat for the predicted transfer functions, efficiency of the predicted transfer functions, or the output of predicted transfer functions. The system also provides a methodology for selecting loudspeaker locations, the number of loudspeakers, the types of loudspeakers, correction factors, listening positions, or a combination of these schemes in an audio system that has a single listening position or multiple listening positions.

Claims

1. A method for selecting at least one correction factor for an audio system, the method comprising:

generating acoustic signals from at least one loudspeaker placed at potential loudspeaker locations;

recording transfer functions for the generated acoustic signals at a plurality of listening positions;

determining at least one potential correction factor;

modifying the transfer functions based on the potential correction factors in order to generate predicted transfer functions;

statistically analyzing across at least one frequency of the predicted transfer functions for the plurality of listening positions; and

selecting a correction factor based on the statistical analysis.

2. The method of claim 1, where the potential correction factor is a non-temporal correction factor.

3. The method of claim 2, where the non-temporal correction factor is selected from the group consisting of gain, amplitude, and equalization.

4. The method of claim 3, where the equalization is selected from the group consisting of parametric, graphic, paragraphic, shelving, FIR (finite impulse response), and transversal equalization.

5. The method of claim 1, where the potential correction factor is a temporal correction factor.

6. The method of claim 1, where the statistical analysis indicates efficiency of the predicted transfer functions for the plurality of listening positions.

7. The method of claim 6, where efficiency is examined for predetermined frequencies.

8. The method of claim 7, where selecting a correction factor based on the statistical analysis comprises selecting a value for the correction factor to increase efficiency of the audio system in the predetermined frequencies.

9. The method of claim 8, where the potential correction factor comprises potential volume correction;

and

where selecting a value to increase efficiency comprises selecting a value that decreases volume of at least one of the loudspeakers in the audio system.

10. The method of claim 1, where the statistical analysis indicates consistency of the predicted transfer functions across the plurality of listening positions.

11. The method of claim 1, where the statistical analysis indicates flatness for the predicted transfer functions.

12. A machine readable medium having software for causing a computer to execute a method, the machine readable medium comprising:

instructions for generating acoustic signals from at least one loudspeaker placed at potential loudspeaker locations;

instructions for recording transfer functions for the generated acoustic signals at a plurality of listening positions;

instructions for determining at least one potential correction factor;

instructions for modifying the transfer functions based on the potential correction factors in order to generate predicted transfer functions;

instructions for statistically analyzing across at least one frequency of the predicted transfer functions for the plurality of listening positions; and

instructions for selecting a correction factor based on the statistical analysis.

13. The machine readable medium of claim 12, where the statistical analysis indicates efficiency of the predicted transfer functions for the plurality of listening positions.

14. The machine readable medium of claim 12, where the statistical analysis indicates consistency of the predicted transfer functions across the plurality of listening positions.

15. The machine readable medium of claim 12, where the statistical analysis indicates flatness for the predicted transfer functions.

16. The signal-bearing medium of claim 12, further comprising logic for recommending a specific correction factor.

17. In an audio system comprising at least one loudspeaker and at least one listening position, a method for selecting at least one correction factor for the audio system, the method comprising:

recording transfer functions at the listening position;

determining potential correction factors;

modifying the transfer functions based on the potential correction factors in order to generate predicted transfer functions;

statistically analyzing the predicted transfer functions; and

selecting at least one correction factor based on the statistical analysis.

18. The method of claim 17, where the potential correction factor is a non-temporal correction factor.

19. The method of claim 18, where the non-temporal correction factor is selected from the group consisting of gain, amplitude, and equalization.

20. The method of claim 17, where the potential correction factor is a temporal correction factor.

21. The method of claim 17, where the statistical analysis indicates efficiency of the predicted transfer functions.

22. The method of claim 21, where efficiency is examined for predetermined frequencies.

23. The method of claim 22, where selecting a correction factor based on the statistical analysis comprises selecting a value for the correction factor to increase efficiency of the audio system in the predetermined frequencies.

24. The method of claim 23, where the potential correction factor comprises potential volume correction;

and

where selecting a value to increase efficiency comprises selecting a value that decreases volume of at least one of the loudspeakers in the audio system.

25. The method of claim 17, where recording transfer functions comprises recording transfer functions at a plurality of listening positions;

and

where the statistical analysis indicates consistency of the predicted transfer functions across the plurality of listening positions.

26. The method of claim 17, where the statistical analysis indicates flatness for the predicted transfer functions.

27. A signal-bearing medium having instructions for causing a computer to execute a method, the signal-bearing medium comprising:

logic for recording transfer functions at the listening position;

logic for determining potential correction factors;

logic for modifying the transfer functions based on the potential correction factors in order to generate predicted transfer functions;

logic for statistically analyzing the predicted transfer functions.

28. The signal-bearing medium of claim 27, further comprising logic for recommending a specific correction factor.

29. A method for selecting at least one correction factor for audio system comprising:

recording transfer functions at at least one listening position;

determining potential correction factors;

determining potential values for at least one parameter in the audio system modifying the transfer functions based on the potential values in order to generate predicted transfer functions;

statistically analyzing the predicted transfer functions;

modifying the statistical analysis based on the potential correction factors; and

selecting at least one correction factor based on the modified statistical analysis.

30. The method of claim 29, where modifying the statistical analysis comprises applying potential equalization factors.

31. The method of claim 30, where recording transfer functions comprises recording transfer functions at a plurality of listening positions;

where the statistical analysis determines a frequency with a maximum spatial variance for the predicted transfer functions, and

wherein the potential equalization factors are applied at the frequency with the maximum spatial variance for a predicted transfer function.

32. The method of claim 31, where the potential equalization factors comprise a center frequency at the frequency with the maximum variance, a bandwidth setting, a level setting.