Method and apparatus for processing audio signal

Patent metadata

Field	Value
Publication number	US-9131297-B2
Application number	US-201213605422-A
Country	US
Kind code	B2
Filing date	Sep 6, 2012
Priority date	Sep 6, 2011
Publication date	Sep 8, 2015
Grant date	Sep 8, 2015

Abstract

Provided are an audio signal processing apparatus and method. The audio signal processing apparatus includes: a sensing unit for sensing an impedance value of a headphone and adjusting a gain to be applied to an audio signal based on the sensed impedance value; and an amplifier for generating an output audio signal by receiving at least one bias voltage corresponding to the adjusted gain and amplifying the input audio signal according to the adjusted gain. The audio signal processing apparatus is capable of appropriately adjusting the magnitude of an acoustic signal output from a headphone, according to the product specifications of the headphone.

First claim

What is claimed is:

1. An audio signal processing apparatus comprising:
a sensor which determines an impedance value of a headphone, and adjusts a gain to be applied to an audio signal based on the determined impedance value;
a power supplier which adjust at least one bias voltage based on the determined impedance value received from the sensor; and
an amplifier which generates an output audio signal using the adjusted at least one bias voltage from the power supplier and the adjusted gain from the sensor and which amplifies the audio signal generated from the received adjusted at least one bias voltage based on the adjusted gain,
wherein the power supplier adjusts the at least one bias voltage to be proportional to the adjusted gain and adjusts the at least one bias voltage to be equal to or greater than a maximum voltage of the output audio signal, and
wherein the amplifier generates the output audio signal, which is an unclipped output audio signal obtained using the adjusted at least one bias voltage and the proportional adjusted gain.

2. The audio signal processing apparatus of claim 1 , wherein the sensor senses the impedance value in units of frequency bands.

3. The audio signal processing apparatus of claim 2 , wherein the sensor obtains an impedance value characteristic curve of the headphone that varies according to a frequency.

4. The audio signal processing apparatus of claim 2 , wherein the sensor detects an impedance value corresponding to a frequency band corresponding to a direct-current (DC) voltage component, as the impedance value of the headphone.

5. The audio signal processing apparatus of claim 1 , wherein the sensor adjusts the gain to maintain power of the output audio signal at a constant level.

6. The audio signal processing apparatus of claim 1 , further comprising a headphone connector connectable to a plug of the headphone, and
wherein the sensor senses whether the headphone is connected to the headphone connector, and senses the impedance value of the headphone in response to sensing that the headphone is connected to the headphone connector.

7. The audio signal processing apparatus of claim 6 , wherein the headphone connector comprises:
a plug inserter into which the plug of the headphone is insertable;
a third pole connecting terminal connectable to a third pole terminal of the headphone; and
a fourth pole connecting terminal connectable to a fourth pole terminal of the headphone, and
the audio signal processing apparatus further comprises a plug sensor which determines whether the plug is a three-pole plug or a four-pole plug, based on a difference between voltages of the third pole connecting terminal and the fourth pole connecting terminal.

8. The audio signal processing apparatus of claim 1 , further comprising:
a user interface generator which generates a user interface screen for selecting whether the gain applied to the output audio signal is to be adjusted based on the sensed impedance value; and
a display which displays the generated user interlace screen,
wherein the user interface screen comprises:
an impedance field indicating the sensed impedance value of the headphone;
a manual adjustment field in which a user manually inputs the gain; and
a recommended value adjustment field in which a recommended gain is provided which is calculated by the audio signal processing apparatus based on the measured impedance of the headphone.

9. The audio signal processing apparatus of claim 1 , further comprising:
a user interface generator which generates a user interface screen for selecting whether the gain applied to the output audio signal is to be adjusted based on the sensed impedance value; and
a display which displays the generated user interface screen,
wherein the user interface screen comprises:
an impedance field indicating the sensed impedance value of the headphone; and
a gain adjustment interface comprising a recommended gain value field which indicates a recommended gain which is calculated by the audio signal processing apparatus based on the measured impedance of the headphone and a manual adjustment element which is manipulated by a user to adjust the recommended gain.

10. An audio signal processing apparatus comprising:
a sensor which determines an impedance value of a headphone, and adjusts a gain to be applied to an audio signal based on the determined impedance value; and
an amplifier which generates an output audio signal by receiving at least one bias voltage corresponding to the adjusted gain and amplifies the audio signal according to the adjusted gain,
wherein the sensor senses the impedance value of the headphone in units of frequency bands, and
wherein the sensor detects a converging frequency band that is a frequency band in which the impedance value converges to a predetermined value, and obtains an impedance value corresponding to the converging frequency band, as the impedance value of the headphone.

11. The audio signal processing apparatus of claim 10 , wherein the sensor obtains an average of impedance values corresponding to the converging frequency band, as the impedance value of the headphone.

12. A method of processing an audio signal, performed by an audio signal processing apparatus that is connectable to a headphone, the method comprising:
determining an impedance value of the headphone;
adjusting a gain to be applied to the audio signal based on the determined impedance value;
adjusting at least one bias voltage based on the determined impedance value to be proportional to the adjusted gain and to equal to or be greater than a maximum voltage of the output audio signal;
applying the adjusted at least one bias voltage to the amplifier; and
generating the output audio signal by using the adjusted at least one bias voltage and the adjusted gain and amplifying the audio signal generated from the received adjusted at least one bias voltage based on the adjusted gain,
wherein the generated output audio signal is an unclipped output audio signal obtained using the adjusted at least one bias voltage and the proportional adjusted gain.

13. The method of claim 12 , wherein the determining the impedance value of the headphone comprises:
sensing whether the headphone is connected to a headphone connector of the audio signal processing apparatus; and
sensing the impedance value of the headphone in response to sensing that the headphone is connected to the headphone connector.

14. The method of claim 12 , wherein the determining the impedance value of the headphone comprises sensing the impedance value in units of frequency bands.

15. The method of claim 14 , wherein the determining the impedance value of the headphone comprises detecting an impedance value corresponding to a frequency band corresponding to a direct-current (DC) voltage component, as the impedance value of the headphone.

16. The method of claim 12 , wherein the adjusting the gain comprises adjusting the gain to maintain power of the output audio signal at a constant level.

17. A method of processing an audio signal, performed by an audio signal processing apparatus that is connectable to a headphone, the method comprising:
determining an impedance value of the headphone,
adjusting a gain to be applied to the audio signal based on the determined impedance value; and
generating an output audio signal by receiving at least one bias voltage corresponding to the gain adjusted by the determining and amplifying the audio signal according to the adjusted gain,
wherein the determining the impedance value of th

Assignees

• Kim Han-Ki
• Park Hae-Kwang
• Lim Dong-Hyun
• Samsung Electronics Co Ltd

Inventors

• Kim Han-Ki
• Park Hae-Kwang
• Lim Dong-Hyun

Classifications

• H04R1/1041

  Mechanical or electronic switches, or control elements (switches in general H01H) · CPC title

• H03G3/301

  the gain being continuously variable · CPC title

• H04R3/007 Primary

  Protection circuits for transducers · CPC title

• H03G3/30

  in amplifiers having semiconductor devices · CPC title

• H04R3/00 Primary

  Circuits for transducers (arrangements for producing a reverberation or echo sound G10K15/08; amplifiers H03F) · CPC title