Techniques for tuning the distortion response of a loudspeaker

Patent metadata

Field	Value
Publication number	US-9848262-B2
Application number	US-201615078896-A
Country	US
Kind code	B2
Filing date	Mar 23, 2016
Priority date	Mar 23, 2016
Publication date	Dec 19, 2017
Grant date	Dec 19, 2017

Abstract

A corrector is configured to transform audio signals to compensate for unwanted distortion characteristics of a loudspeaker. A tuning filter is configured to transform audio signals to incorporate desired distortion characteristics associated with a target loudspeaker. By chaining together the tuning filter and the corrector, an audio signal can be modified so that the loudspeaker, when outputting the audio signal, has response characteristics of the target loudspeaker.

First claim

What is claimed is:

1. A computer-implemented method for generating a desired response for a loudspeaker, the method comprising:
tuning an audio signal based on a model of a first output device to emulate one or more desired distortion characteristics associated with the first output device to produce a tuned audio signal;
correcting the tuned audio signal to attenuate one or more undesired distortion characteristics associated with a second output device to produce a corrected audio signal;
outputting a final signal, via the second output device, that is based on the corrected audio signal, wherein the final signal includes the one or more desired distortion characteristics associated with the first output device.

2. The computer-implemented method of claim 1 , wherein the final signal includes less or none of the one or more undesired distortion characteristics associated with the second output device.

3. The computer-implemented method of claim 1 , wherein tuning the audio signal comprises modifying the audio signal based on a first transfer function associated with the first output device.

4. The computer-implemented method of claim 3 , wherein the first transfer function indicates both linear and non-linear response characteristics associated with the first output device.

5. The computer-implemented method of claim 3 , further comprising generating the model of the first output device to determine the first transfer function, wherein the model comprises a physical system model, a Hammerstein model, a Volterra kernel, or a lumped parameters model.

6. The computer-implemented method of claim 1 , wherein correcting the tuned audio signal comprises modifying the tuned audio signal based on a second transfer function associated with the second output device.

7. The computer-implemented method of claim 6 , wherein the second transfer function indicates both linear and non-linear response characteristics associated with the second output device.

8. The computer-implemented method of claim 6 , further comprising generating a model of the second output device to determine the second transfer function, wherein the model comprises a physical system model, a Hammerstein model, a Volterra kernel, or a lumped parameters model.

9. A non-transitory computer-readable medium that, when executed by a processor, configures the processor to generate a desired response for a loudspeaker, by performing the steps of:
tuning an audio signal based on a model of a first output device to emulate one or more desired distortion characteristics associated with the first output device to produce a tuned audio signal;
correcting the tuned audio signal to attenuate one or more undesired distortion characteristics associated with a second output device to produce a corrected audio signal;
outputting a final signal, via the second output device, that is based on the corrected audio signal, wherein the final signal includes the one or more desired distortion characteristics associated with the first output device.

10. The non-transitory computer-readable medium of claim 9 , wherein the final signal includes less or none of the one or more undesired distortion characteristics associated with the second output device.

11. The non-transitory computer-readable medium of claim 9 , wherein tuning the audio signal comprises modifying the audio signal based on a first nonlinear transfer function associated with the first output device.

12. The non-transitory computer-readable medium of claim 11 , further comprising estimating a first set of parameters via a gradient descent algorithm to determine the first transfer function, wherein the first set of parameters governs dynamics of the first output device.

13. The non-transitory computer-readable medium of claim 9 , wherein correcting the tuned audio signal comprises modifying the tuned audio signal based on a second nonlinear transfer function associated with the second output device.

14. The non-transitory computer-readable medium of claim 13 , further comprising estimating a second set of parameters via a gradient descent algorithm to determine the second transfer function, wherein the second set of parameters governs dynamics of the second output device.

15. A system configured to generate a desired response for a loudspeaker, comprising:
a memory storing an emulation application; and
a processor coupled to the memory that, when executing the emulation application, is configured to:
tune an audio signal based on a model of a first output device to emulate one or more desired distortion characteristics associated with the first output device to produce a tuned audio signal,
correct the tuned audio signal to attenuate one or more undesired distortion characteristics associated with a second output device to produce a corrected audio signal,
output a final signal, via the second output device, that is based on the corrected audio signal, wherein the final signal includes the one or more desired distortion characteristics associated with the first output device.

16. The system of claim 15 , wherein the final signal includes less or none of the one or more undesired distortion characteristics associated with the second output device.

17. The system of claim 15 , wherein the processor is configured to tune the audio signal by modifying the audio signal based on a first nonlinear transfer function associated with the first output device.

18. The system of claim 15 , wherein the processor is configured to correct the tuned audio signal by modifying the tuned audio signal based on a second nonlinear transfer function associated with the second output device.

19. The system of claim 18 , wherein the processor modifies the tuned audio signal by applying an inverse of the second transfer function to the tuned audio signal.

20. The system of claim 15 , wherein the first output device comprises a first amplifier for amplifying musical instruments and the second output device comprises a second amplifier for amplifying a musical instrument configured to generate the audio signal.

Assignees

• Harman Int Ind

Inventors

• Iyer Ajay
• Hutchings Jeffrey
• Kreifeldt Richard Allen

Classifications

• G10H2210/311

  Distortion, i.e. desired non-linear audio processing to change the tone colour, e.g. by adding harmonics or deliberately distorting the amplitude of an audio waveform · CPC title

• H04R3/04 Primary

  for correcting frequency response · CPC title

• G10H3/187

  for distorting the signal, e.g. to simulate tube amplifiers (changing the tone color by non-linear elements G10H1/16) · CPC title

• H04R29/001

  for loudspeakers (H04R29/007 takes precedence) · CPC title

• G10H1/125

  using a digital filter · CPC title