Audio tuning system

• US 20070025559A1
• Filed: 07/31/2006
• Published: 02/01/2007
• Est. Priority Date: 07/29/2005
• Status: Active Grant

• Current Assignee: Harman International Industries Incorporated (Samsung Electronics Co. Ltd.)
• Original Assignee: Harman International Industries Incorporated (Samsung Electronics Co. Ltd.)
• Inventors: Mihelich, Ryan, Eid, Bradley
• Granted Patent: US 8,082,051 B2
• Time in Patent Office: Days
• US Class Current: 381/59
• CPC Class Codes: H04R 2499/13 Acoustic transducers and sound field adaptation in vehicles
• CPC Class Codes: H04R 29/001 for loudspeakers H04R29/007 takes precedence
• CPC Class Codes: H04R 3/14 Cross-over networks
• CPC Class Codes: H04S 7/301 Automatic calibration of stereophonic sound system, e.g. with test microphone
• CPC Class Codes: H04S 7/307 Frequency adjustment, e.g. tone control H04S7/301 takes precedence

Abstract

An audio system installed in a listening space may include a signal processor and a plurality of loudspeakers. The audio system may be tuned with an automated audio tuning system to optimize the sound output of the loudspeakers within the listening space. The automated audio tuning system may provide automated processing to determine at least one of a plurality of settings, such as channel equalization settings, delay settings, gain settings, crossover settings, bass optimization settings and group equalization settings. The settings may be generated by the automated audio tuning system based on an audio response produced by the loudspeakers in the audio system. The automated tuning system may generate simulations of the application of settings to the audio response to optimize tuning.

Claims

1. An automated audio tuning system executable on a computer, comprising:

a setup file configured to store audio system specific configuration settings for an audio system to be tuned;

a transfer function matrix configured to store a plurality of in-situ measured audio responses receivable from a plurality of loudspeakers;

a laboratory response matrix configured to store a plurality of laboratory measured audio responses;

a channel equalization engine executable to generate channel equalization settings for each of a plurality of amplified channels based on the in-situ audio responses or the measured audio responses, or a combination thereof;

a crossover engine executable to generate a crossover setting for a selected group of amplified channels based on the in-situ audio responses or the measured audio responses, or a combination thereof with the channel equalization settings applied thereto; and

a system optimization engine executable to generate equalization settings applicable to a group of the amplified channels based on the in-situ measure audio responses with the channel equalization settings and crossover settings applied thereto.

2. The automated audio tuning system of claim 1, further comprising a delay engine executable to generate delay settings for each of the amplified channels based on the in-situ audio responses.

3. The automated audio tuning system of claim 2, further comprising a gain engine executable to generate a gain for each of the amplified channels based on the in-situ measured audio responses to optimize an output level of each of the amplified channels.

4. The automated audio tuning system of claim 1, further comprising a bass optimization engine executable to generate a phase adjustment of each of a plurality amplified channels in a selected group based on the in-situ measured audio responses, and the audio system specific configuration settings to optimize summation of the in-situ measured audio responses of the selected group.

5. The automated audio tuning system of claim 4, where the amplified channels in the selected group are indicated in the audio system specific configuration settings as driving loudspeakers operable in a determined frequency range.

6. The automated audio tuning system of claim 5, where the determined frequency range is at or below about 400 Hz.

7. The automated audio tuning system of claim 1, where the transfer function matrix comprises a three-dimensional matrix comprising a plurality of audio channels corresponding to a plurality of microphone based response measurements, within a plurality of different frequencies.

8. The automated audio tuning system of claim 6, further comprising a spatial averaging engine executable to spatially average the transfer function matrix by averaging the plurality of microphone based response measurements for each of the audio channels.

9. The automated audio tuning system of claim 7, where the spatially averaged transfer function is further executable to weight the microphone based response measurements with weighting factors included in the setup file.

10. The automated audio tuning system of claim 7, where the channel equalization engine and the crossover engine are executable to generate respective channel equalization settings and crossover settings with the spatially averaged transfer function matrix.

11. The automated audio tuning system of claim 3, further comprising a setting applications simulator engine executable to generate a simulation of application to the measured audio responses of at least one of the channel equalization settings, the delay settings, the gain, or the crossover settings, or any combination thereof.

12. An automated audio tuning system executable on a computer, comprising:

a setup file configured to store audio system specific configuration settings for an audio system to be tuned;

a response matrix configured to store a plurality of measured audio responses receivable from a plurality of loudspeakers; and

a crossover engine executable to generate a crossover setting for at least two of a plurality of amplified channels in the audio system, where the at least two amplified channels are each configured in the setup file to drive loudspeakers operable in at least partially different frequency ranges, and where the crossover engine is executable to generate crossover settings to optimize a combined response of the loudspeakers.

13. The automated audio tuning system of claim 12, further comprising a channel equalization engine executable to generate channel equalization settings for each of a plurality of amplified channels to adjust a frequency response of the measured audio responses based on the audio system specific configuration settings.

14. The automated audio tuning system of claim 13, further comprising a delay engine executable to generate delay settings for each of the amplified channels based on the measured audio responses.

15. The automated audio tuning system of claim 14, further comprising a system optimization engine executable to generate group equalization settings applicable to a group of the amplified channels based on the audio responses with the channel equalization settings, delay settings, gain settings, and crossover settings applied thereto.

16. The automated audio tuning system of claim 14, where the crossover engine is executable to generate crossover settings based on the audio responses that have been equalized with the channel equalization settings and delayed with the delay settings.

17. The automated audio tuning system of claim 12, where the crossover engine is executable to generate the crossover settings with at least one of a parametric engine or a non-parametric engine, or a combination thereof.

18. The automated audio tuning system of claim 12, where the response matrix comprises an in-situ response matrix configured to store a plurality of in-situ measured audio responses and a laboratory response matrix configured to store a plurality of laboratory measured audio responses.

19. The automated audio tuning system of claim 18, where the in-situ measured audio responses are loudspeaker responses measured in a vehicle.

20. An automated audio tuning system executable on a computer, comprising:

a setup file configured to store audio system specific configuration settings for an audio system to be tuned;

a response matrix configured to store a plurality of measured audio responses receivable from a plurality of loudspeakers; and

a bass optimization engine executable to generate a phase adjustment for each of a plurality of amplified channels in a determined group of amplified channels included in the audio system based on the measured audio responses and the audio system specific configuration settings to optimize summation of the audio responses of the determined group of amplified channels.

21. The automated audio tuning system of claim 20, where the audio responses are in-situ measured audio responses.

22. The automated audio tuning system of claim 20, where the determined group is selected based on indication in the setup file that each of the amplified channels is configured to drive a loudspeaker in a determine frequency range.

23. The automated audio tuning system of claim 22, where the determined frequency range is between about 0 Hz and about 150 Hz.

24. The automated audio tuning system of claim 20, where the phase adjustment of at least two of the amplified channels is different.

25. The automated audio tuning system of claim 20, where the bass optimization engine is executable to generate the phase adjustment with at least one of a parametric engine or a non-parametric engine, or a combination thereof.

26. The automated audio tuning system of claim 20, where the bass optimization engine includes a direct optimization engine executable to directly determine an optimized phase adjustment for each of the amplified channels in the group, and an iterative optimization engine executable to iteratively determine an optimized phase adjustment for each of the amplified channels in the group.

27. The automated audio tuning system of claim 26, where determination of the optimized phase adjustments with one of the direct optimization engine or the iterative optimization engine, or a combination thereof, is based on an optimization engine designation that is settable in the setup file.

28. An automated audio tuning system comprising:

a memory device;

instructions stored in the memory device to store in a setup file, and retrieve from the setup file, audio system specific configuration information;

instructions stored in the memory device to capture and store in a response matrix a plurality of audio responses receivable from a plurality of loudspeakers in an audio system;

instructions stored in the memory device to generate a plurality of channel equalization settings for each of a plurality of amplified channels based on the audio responses and the audio system specific configuration information; and

instructions stored in the memory device to apply the channel equalization settings to the response matrix, and to generate a crossover setting for at least two amplified channels based on the equalized audio responses and indication in the audio system specific configuration information that the at least two amplified channels are each configured to drive respective loudspeakers operable in different frequency ranges.

29. The automated audio tuning system of claim 28, further comprising instructions stored in the memory device to apply the generated crossover setting to the equalized audio responses, and to generate group equalization settings applicable to groups of the amplified channels based on the equalized audio response with the crossover setting applied thereto.

30. The automated audio tuning system of claim 28, further comprising instructions stored in the memory device to generate a plurality of delay settings based on the audio responses and the audio system specific configuration information.

31. The automated audio tuning system of claim 30, further comprising instructions stored in the memory device to apply the delay settings to the response matrix, and to generate a plurality of bass optimization settings to adjust the phase of a determined group of the amplified channels based on the delayed audio responses.

32. The automated audio tuning system of claim 28, where the instructions to generate the crossover settings further comprise instructions stored in the memory device to identify, from the audio system specific configuration information, at two amplified output channels of the audio system that are configured to drive respective loudspeakers that, in combination, are operable to produce a frequency range of audible sound that is larger than a frequency range of audible sound the loudspeakers are operable to produce individually, and instructions to generate crossover settings for only the identified at least two amplified output channels as a function of the audible sound the loudspeakers are operable to produce individually.

33. The automated audio tuning system of claim 28, further comprising instructions stored in the memory device to enable download of the generated settings into the audio system.

34. The automated audio tuning system of claim 28, where the instructions to generate the crossover settings further comprise instructions stored in the memory device to generate non-parametric coefficients for the cross-over settings based on a constraint stored in the setup file.

35. The automated audio tuning system of claim 29, where the instructions to generate the group equalization settings further comprise instructions stored in the memory device to compare the equalized audio responses with the crossover settings applied thereto to a target function, and generate the group equalization settings that adjust the equalized audio responses with the crossover settings applied thereto to optimally match the target function.

36. A method of automated sound system tuning, the method comprising:

entering audio system specific configuration information in a setup file;

storing a plurality of audio responses for a plurality of loudspeakers included in the audio system specific configuration;

identifying with a crossover engine, from the audio system specific configuration information, at least two amplified audio channels from which respective loudspeakers will be drivable in different frequency ranges;

generating a crossover setting with the crossover engine, based on optimization of a simulated combined response of the loudspeakers; and

tuning groups of amplified audio channels with group equalization settings, and phase adjustments between amplified audio channels, based on simulated application of the crossover settings to the amplified audio channels as applied to the system specific configuration information included in the setup file.

37. The method of claim 36, where tuning groups of the amplified audio channels with group equalization settings, and phase adjustments between amplified channels comprises iteratively determining bass optimization settings to achieve maximal summation of a determined frequency range of a group of amplified audio channels selected based on audio system specific configuration information included in the setup file.

38. The method of claim 36, where tuning groups of the amplified audio channels with group equalization settings, and phase adjustments between amplified audio channels comprises iteratively determining group equalization settings for a group of amplified audio channels based on comparison of a simulated response of the group of amplified audio channels to a target function.

39. The method of claim 36, where generating a crossover setting comprises generating an optimized crossover setting with one of a parametric engine or a non-parametric engine, or a combination thereof, and one of a direct optimization engine or an iterative optimization engine, or a combination thereof.

40. The method of claim 36, further comprising generating channel equalization, gain, and delay settings for each of a plurality of amplified audio channels based on the setup file, and simulated application of the audio responses to the system specific configuration information.

41. The method of claim 39, where generating channel equalization, gain and delay settings for each of a plurality of amplified audio channels comprises generating an optimized channel equalization setting for each of the amplified output channels with one of a parametric engine or a non-parametric engine, or a combination thereof, and one of a direct optimization engine or an iterative optimization engine, or a combination thereof.

42. A computer readable medium having computer executable modules for an automated audio tuning system comprising:

an amplified channel equalization engine executable to generate a response correction for a plurality of amplified audio channels based on a response of loudspeakers indicated as being drivable by the amplified audio channels;

a settings application simulator engine executable to simulate application of the generated response corrections to the response of loudspeakers;

a crossover engine executable to generate a crossover setting in accordance with the response corrected response of loudspeakers for at least two of the amplified audio channels, where the at least two of the amplified audio channels are each designated to drive a respective loudspeaker operable in a different frequency range;

the settings application simulator engine further executable to simulate application of the generated response corrections and crossover settings to the response of loudspeakers; and

a system optimization engine executable to generate a response correction, or a phase correction, or a combination thereof, for groups of amplified audio channels based on the simulated response corrected and selectively crossed-over response of loudspeakers.