System and method for digital signal processing

• US 10,291,195 B2
• Filed: 10/17/2017
• Issued: 05/14/2019
• Est. Priority Date: 02/07/2006
• Status: Active Grant

• Current Assignee: Bongiovi Acoustics LLC
• Original Assignee: Bongiovi Acoustics LLC
• Inventors: Bongiovi, Anthony, Fuller, Phillip, Zelniker, Glenn
• Primary Examiner(s): Patel, Yogeshkumar
• Application Number:
  US15/786,099
• Publication Number:
  US 20180091109A1
• Time in Patent Office: 574 Days
• CPC Class Codes: H03G 3/20 Automatic control H03G3/005 takes precedence; combined with volume compression or expansion H03G7/00
• CPC Class Codes: H03G 5/005 of digital signals
• CPC Class Codes: H03G 5/165 Equalizers; Volume or gain control in limited frequency bands
• CPC Class Codes: H04R 2499/13 Acoustic transducers and sound field adaptation in vehicles
• CPC Class Codes: H04R 3/12 for distributing signals to two or more loudspeakers specially adapted for hearing aids H04R25/407
• CPC Class Codes: H04S 7/307 Frequency adjustment, e.g. tone control H04S7/301 takes precedence

Abstract

The present invention provides methods and systems for digitally processing audio signals. Some embodiments receive an audio signal and converting it to a digital signal. The gain of the digital signal may be adjusted a first time, using a digital processing device located between a receiver and a driver circuit. The adjusted signal can be filtered with a first low shelf filter. The systems and methods may compress the filtered signal with a first compressor, process the signal with a graphic equalizer, and compress the processed signal with a second compressor. The gain of the compressed signal can be adjusted a second time. These may be done using the digital processing device. The signal may then be output through an amplifier and driver circuit to drive a personal audio listening device. In some embodiments, the systems and methods described herein may be part of the personal audio listening device.

Claims

1. A method for processing a digital signal comprising:

adjusting a gain of the digital signal a first time using a digital processing device to create a first adjusted signal;

processing the first adjusted signal with a first low shelf filter and a first high shelf filter to create a first filtered signal;

compressing the first filtered signal with a first compressor to create a first compressed signal;

processing the first compressed signal with a second low shelf filter and a second high shelf filter to create a second filtered signal;

processing the second filtered signal with a graphic equalizer to create an equalized signal;

compressing the equalized signal with a second compressor to create a second compressed signal;

adjusting the gain of the second compressed signal a second time to create a second adjusted signal, wherein the adjustment comprises a gain reduction if the gain of the second compressed signal is above a predetermined threshold; and

outputting the second adjusted signal through an amplifier and driver circuit in a personal audio listening device.

2. The method of claim 1, comprising a plurality of independent digital processing devices to process and compress the signals.

3. The method of claim 1, wherein the personal audio listening device is a pair of headphones.

4. The method of claim 3, wherein the personal audio listening device is used within a vehicle.

5. The method of claim 4, further comprising creating a sound profile for a vehicle where the personal audio listening device will be used.

6. The method of claim 1, wherein the audio signal is received wirelessly.

7. The method of claim 1, wherein the digital signal represents an audio signal.

8. The method of claim 1, wherein adjusting the gain of the received signal a first time is done with a first gain amplifier and adjusting the gain of the signal a second time is done with a second gain amplifier.

9. The method of claim 1, wherein the first low shelf filter has a cutoff frequency at 1000 Hz.

10. The method of claim 1, wherein the first high shelf filter has a cutoff frequency at 1000 Hz.

11. The method of claim 1, wherein the graphic equalizer comprises eleven cascading second order filters.

12. The method of claim 11, wherein each of the second order filters is a bell filter.

13. The method of claim 12, wherein the first of the eleven filters has a center frequency of 30 Hz and the eleventh filter of the eleven filters has a center frequency of 16000 Hz.

14. The method of claim 13, wherein the second to tenth filters are centered at approximately one octave intervals from each other.

15. The audio system of claim 1, wherein the second low shelf filter is a magnitude-complementary low-shelf filter.

16. The audio system of claim 1, further comprising a set of headphones coupled to the driver circuit.

17. The audio system of claim 1 wherein at least one of said digital processing devices is disposed remotely from one or more other digital processing devices.