Sound reproducing system and sound reproducing method

• US 20080187156A1
• Filed: 09/20/2007
• Published: 08/07/2008
• Est. Priority Date: 09/22/2006
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Yokota, Teppei
• Granted Patent: US 8,194,898 B2
• Time in Patent Office: Days
• US Class Current: 381/307
• CPC Class Codes: H04R 1/025 Arrangements for fixing loudspeaker transducers, e.g. in a box, furniture
• CPC Class Codes: H04R 1/028 associated with devices performing functions other than acoustics, e.g. electric candles
• CPC Class Codes: H04R 2420/07 Applications of wireless loudspeakers or wireless microphones
• 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 2420/01 Enhancing the perception of the sound image or of the spatial distribution using head related transfer functions [HRTF's] or equivalents thereof, e.g. interaural time difference [ITD] or interaural level difference [ILD]
• CPC Class Codes: H04S 3/008 in which the audio signals are in digital form, i.e. employing more than two discrete digital channels data reduction aspects thereof based on psychoacoustics G10L19/02

Abstract

A sound reproducing system includes a first speaker that is supplied with audio signals of a first channel and that is placed so that a reproduced sound image generated by the audio signals of the first channel is localized in a position in a front direction of a listener; a pair of second speakers that are supplied with audio signals on which a virtual sound source process is performed; a virtual sound source processing unit to perform the virtual sound source process on the audio signals of a plurality of channels; a volume detecting unit to detect the volumes of the first channel and the other channels; a volume comparing unit to compare the volume of the first channel with each of the volumes of the other channels; and a control unit to control the gains of the audio signals of the first channel and the other channels.

Claims

1. A sound reproducing system to reproduce audio signals of a plurality of channels including a first channel in which a reproduced sound image is localized in a position in a front direction of a listener, the sound reproducing system comprising:

a first speaker that is supplied with first audio signals of the first channel and that is placed so that a first reproduced sound image generated by the first audio signals of the first channel is localized in a position in the front direction of the listener;

a pair of second speakers that are supplied with second audio signals on which a virtual sound source process is performed so that a second reproduced sound image is localized in a predetermined position;

virtual sound source processing means for performing the virtual sound source process on the audio signals of the plurality of channels so as to generate the second audio signals to be supplied to the second speakers;

volume detecting means for detecting a volume of the first channel from the first audio signals of the first channel and detecting volumes of channels other than the first channel from other audio signals of the other channels;

volume comparing means for comparing the volume of the first channel with each of the volumes of the other channels detected by the volume detecting means; and

control means for controlling the gains of the first audio signals of the first channel and the other channels based on a comparison result generated by the volume comparing means.

2. The sound reproducing system according to claim 1,

wherein, if it is determined that the volume of the first channel is relatively larger than each of the volumes of the other channels, the control means performs gain control to decrease the volume of the first audio signals of the first channel among the audio signals of the plurality of channels to be supplied to the virtual sound source processing means.

3. The sound reproducing system according to claim 1,

wherein, if it is determined that the volume of the first channel is relatively larger than each of the volumes of the other channels, the control means performs control to remove the first audio signals of the first channel from the audio signals of the plurality of channels to be supplied to the virtual sound source processing means.

4. The sound reproducing system according to claim 1,

wherein, if it is determined that the volume of the first channel is relatively larger than each of the volumes of the other channels, the control means controls the gain of the first audio signals of the first channel in order to increase the volume of the first channel.

5. The sound reproducing system according to claim 4,

wherein, if it is determined that the volume of the first channel is relatively larger than each of the volumes of the other channels, the control means performs control so that the audio signals on which the virtual sound source process is performed are supplied to the second speakers while being delayed so that sound is emitted therefrom at timing later than sound emission timing in the first speaker.

6. The sound reproducing system according to claim 1,

wherein, among the audio signals to be supplied to the second speakers after the virtual sound source process is performed thereon, at least the audio signals of the same channel as that of the audio signals to be supplied to the first speaker are delayed so that sound is emitted from the second speakers later than sound emission timing in the first speaker.

7. The sound reproducing system according to claim 1,

wherein the second speakers are held by holding means at predetermined positions near the ears of the listener, and wherein speaker units of the second speakers are not attached to a baffle plate so that sound components output from front and rear sides of vibrating plates of the speaker units can be added to each other.

8. The sound reproducing system according to claim 1,

wherein the audio signals of the plurality of channels are audio signals of a multi-channel surround method, and

wherein the first audio signals of the first channel are audio signals of a center channel.

9. The sound reproducing system according to claim 8,

wherein the first speaker includes two speakers for two front-left and front-right channels, and

wherein the first audio signals of the center channel of the first channel are added to the audio signals of the front-left channel and the front-right channel, respectively.

10. A sound reproducing method in a sound reproducing system including

a first speaker that is supplied with first audio signals of a first channel among audio signals of a plurality of channels including the first channel in which a reproduced sound image is localized in a position in a front direction of a listener and that is placed so that a first reproduced sound image generated by the first audio signals of the first channel is localized in a position in the front direction of the listener;

a pair of second speakers that are supplied with second audio signals on which a virtual sound source process is performed so that a second reproduced sound image is localized at a predetermined position; and

virtual sound source processing means for performing the virtual sound source process on the audio signals of the plurality of channels so as to generate the second audio signals to be supplied to the second speakers,

the sound reproducing method comprising the steps of;

comparing the volume of the first audio signals of the first channel to be supplied to the first speaker with each of the volumes of the other audio signals of the other channels, the comparison being performed by volume comparing means of the sound reproducing system; and

controlling gains of the first audio signals of the first channel and the other channels based on a comparison result generated in the volume comparing step.

11. A sound reproducing apparatus comprising:

virtual sound source processing means that is supplied with audio signals of a plurality of channels including a first channel in which a reproduced sound image is localized in a position in a front direction of a listener and that performs a virtual sound source process on the audio signals of the plurality of channels so as to generate processed audio signals to be supplied to a pair of speakers;

an output circuit for outputting first audio signals of the first channel to a front speaker placed in the front direction of the listener;

volume detecting means for detecting a volume of the first channel from the first audio signals of the first channel and detecting volumes of channels other than the first channel from other audio signals of the other channels; and

control means for controlling gains of the first audio signals of the first channel and the other channels based on a comparison result of the volume of the first channel and the volumes of the other channels detected by the volume detecting means.

12. A sound reproducing system to reproduce audio signals of a plurality of channels including a first channel in which a reproduced sound image is localized in a position in a front direction of a listener, the sound reproducing system comprising:

a first speaker that is supplied with first audio signals of the first channel and that is placed so that a first reproduced sound image generated by the first audio signals of the first channel is localized in a position in the front direction of the listener;

a pair of second speakers that are supplied with second audio signals on which a virtual sound source process is performed so that a second reproduced sound image is localized in a predetermined position;

a virtual sound source processing unit configured to perform the virtual sound source process on the audio signals of the plurality of channels so as to generate second audio signals to be supplied to the second speakers;

a volume detecting unit configured to detect a volume of the first channel from the first audio signals of the first channel and detect volumes of channels other than the first channel from the audio signals of the other channels;

a volume comparing unit configured to compare the volume of the first channel with each of the volumes of the other channels detected by the volume detecting unit; and

a control unit configured to control gains of the audio signals of the first channel and the other channels based on a comparison result generated by the volume comparing unit.

13. A sound reproducing apparatus comprising:

a virtual sound source processing unit that is supplied with audio signals of a plurality of channels including a first channel in which a reproduced sound image is localized in a position in a front direction of a listener and that performs a virtual sound source process on the audio signals of the plurality of channels so as to generate processed audio signals to be supplied to a pair of speakers;

an output circuit configured to output first audio signals of the first channel to a front speaker placed in the front direction of the listener;

a volume detecting unit configured to detect a volume of the first channel from the first audio signals of the first channel and detect volumes of the channels other than the first channel from other audio signals of the other channels; and

a control unit configured to control gains of the audio signals of the first channel and the other channels based on a comparison result of the volume of the first channel and the volumes of the other channels detected by the volume detecting unit.