Orientation-Responsive Acoustic Array Control

• US 20120263325A1
• Filed: 04/14/2011
• Published: 10/18/2012
• Est. Priority Date: 04/14/2011
• Status: Active Grant

• Current Assignee: Bose Corporation
• Original Assignee: Bose Corporation
• Inventors: Freeman, Eric J., Joyce, John
• Granted Patent: US 9,253,561 B2
• Time in Patent Office: Days
• US Class Current: 381/120
• CPC Class Codes: H04R 1/02 Casings; Cabinets ; Supports therefor; Mountings therein H04R1/28 takes precedence ; attachments for microphones H04R1/08; mounting of transducers in earpieces H04R1/1075
• CPC Class Codes: H04R 1/24 Structural combinations of separate transducers or of two parts of the same transducer and responsive respectively to two or more frequency ranges
• CPC Class Codes: H04R 1/2807 Enclosures comprising vibrating or resonating arrangements for the reduction of undesired resonances or vibrations H04R1/2869
• CPC Class Codes: H04R 1/2811 for loudspeaker transducers
• CPC Class Codes: H04R 1/34 by using a single transducer with sound reflecting, diffracting, directing or guiding means specially adapted for hearing aids H04R25/402
• CPC Class Codes: H04R 2201/025 Transducer mountings or cabinet supports enabling variable orientation of transducer of cabinet
• CPC Class Codes: H04R 2203/12 Beamforming aspects for stereophonic sound reproduction with loudspeaker arrays
• CPC Class Codes: H04R 2205/022 Plurality of transducers corresponding to a plurality of sound channels in each earpiece of headphones or in a single enclosure
• CPC Class Codes: H04R 2205/024 Positioning of loudspeaker enclosures for spatial sound reproduction
• CPC Class Codes: H04R 2430/25 Array processing for suppression of unwanted side-lobes in directivity characteristics, e.g. a blocking matrix
• CPC Class Codes: H04R 2499/13 Acoustic transducers and sound field adaptation in vehicles
• CPC Class Codes: H04R 2499/15 Transducers incorporated in visual displaying devices, e.g. televisions, computer displays, laptops
• CPC Class Codes: H04R 29/005 Microphone arrays
• CPC Class Codes: H04R 3/005 for combining the signals of two or more microphones specially adapted for hearing aids H04R25/407
• CPC Class Codes: H04R 3/12 for distributing signals to two or more loudspeakers specially adapted for hearing aids H04R25/407
• CPC Class Codes: H04R 3/14 Cross-over networks
• CPC Class Codes: H04R 5/02 Spatial or constructional arrangements of loudspeakers
• CPC Class Codes: H04R 5/04 Circuit arrangements, e.g. for selective connection of amplifier inputs/outputs to loudspeakers, for loudspeaker detection, or for adaptation of settings to personal preferences or hearing impairments combinations of amplifiers H03F3/68; stereophonic systems H04S
• 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
• 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 device incorporates a plurality of acoustic drivers and employs them to form either a first acoustic interference array generating destructive interference in a first direction from the plurality of acoustic drivers or a second acoustic interference array generating destructive interference in a second direction from the plurality of acoustic drivers in response to the orientation of the casing of the audio device relative to the direction of the force of gravity.

Claims

1. An audio device comprising:

a casing rotatable about an axis between a first orientation and a second orientation different from the first orientation;

an orientation input device disposed on the casing to enable determination of an orientation of the casing relative to the direction of the force of gravity;

a plurality of acoustic drivers disposed on the casing and operable to form an acoustic interference array; and

wherein;

the plurality of acoustic drivers are operated to generate destructive interference in a first direction from the plurality of acoustic drivers in response to the casing being in the first orientation; and

the plurality of acoustic drivers are operated to generate destructive interference in a second direction from the plurality of acoustic drivers in response to the casing being in the second orientation.

2. The audio device of claim 1, wherein:

the casing has an elongate shape extending along the axis; and

the plurality of acoustic drivers are disposed on the casing and form a laterally extending row when the casing is rotated to either the first orientation or the second orientation.

3. The audio device of claim 2, wherein each acoustic driver of the plurality of acoustic drivers is disposed on the casing in an orientation causing other axes that are each coincident with a direction of maximum acoustic radiation of each acoustic driver to intersect the axis.

4. The audio device of claim 3, wherein the directions of maximum acoustic radiation of all of the acoustic drivers of the plurality of acoustic drivers are in parallel.

5. The audio device of claim 4, wherein:

the audio device is a portion of an audio system comprising the audio device and a subwoofer having a separate casing;

the audio device and the subwoofer cooperate in acoustically outputting audio received from another device such that the audio device acoustically outputs a portion of the received audio comprising mid-range and higher frequency sounds and such that the subwoofer acoustically outputs a portion of the received audio comprising lower frequency sounds; and

wherein the audio device comprises a wireless transmitter to provide the subwoofer with at least the lower frequency sounds.

6. The audio device of claim 1, wherein the orientation input device comprises a gravity detector comprising an accelerometer.

7. The audio device of claim 1, wherein the orientation input device comprises a manually operable control.

8. The audio device of claim 1, wherein:

the first direction relative to the plurality of acoustic drivers is selected to extend towards a listening position at which a listener is expected to be located at a time when the casing is in the first orientation; and

the second direction relative to the plurality of acoustic drivers is selected to extend towards the listening position at a time when the casing is in the second orientation.

9. The audio device of claim 1, wherein:

the first direction relative to the plurality of acoustic drivers is selected to extend along a direction of maximum acoustic radiation of one of the acoustic drivers of the plurality of acoustic drivers; and

the second direction relative to the plurality of acoustic drivers is perpendicular to the first direction relative to the plurality of acoustic drivers.

10. The audio device of claim 1, further comprising:

a processing device;

a plurality of digital-to-analog converters accessible by the processing device;

a plurality of audio amplifiers of which each audio amplifier is coupled to an output of a digital-to-analog converter of the plurality of digital-to-analog converters, and of which each audio amplifier is coupled to an acoustic driver of the plurality of acoustic drivers;

a storage accessible by the processing device in which is stored a control routine comprising a sequence of instructions that when executed by the processing device, causes the processing device to;

monitor the orientation input device to determine the orientation of the casing;

provide a first plurality of coefficients to a plurality of filters to cause the plurality of acoustic drivers to be operated to generate destructive interference in the first direction relative to the plurality of acoustic drivers in response to determining that the casing is in the first orientation, wherein each filter of the plurality of filters is accessible by the processing device and an output of each filter of the plurality of filters is provided as an input to one of the digital-to-analog converters; and

provide a second plurality of coefficients to the plurality of filters to cause the plurality of acoustic drivers to be operated to generate destructive interference in the second direction relative to the plurality of acoustic drivers in response to determining that the casing is in the second orientation.

11. The audio device of claim 10, wherein the processing device is further caused by execution of the sequence of instructions to instantiate each filter of the plurality of filters.

12. The audio device of claim 10, wherein:

the first and second pluralities of coefficients are stored within the storage; and

the processing device is further caused by the execution of the sequence of instructions to retrieve one or the other of the first and second pluralities of coefficients in response to determining the orientation of the casing to be in one of the first and second orientations.

13. A method comprising:

detecting an orientation of a casing of an audio device about an axis relative to a direction of the force of gravity;

operating a plurality of acoustic drivers disposed on the casing to generate destructive interference in a first direction relative to the plurality of acoustic drivers in response to the casing being in a first orientation about the axis relative to the direction of the force of gravity; and

operating the plurality of acoustic drivers to generate destructive interference in a second direction relative to the plurality of acoustic drivers in response to the casing being in a second orientation about the axis relative to the direction of the force of gravity.

14. The method of claim 13, wherein the first and second directions are perpendicular to each other.

15. The method of claim 14, wherein the first and second directions of maximum acoustic radiation intersect the axis at a common point along the axis.

16. The method of claim 13, wherein:

the first direction relative to the plurality of acoustic drivers is selected to extend towards a listening position at which a listener is expected to be located at a time when the casing is in the first orientation; and

the second direction relative to the plurality of acoustic drivers is selected to extend towards the listening position at a time when the casing is in the second orientation.

17. The method of claim 13, wherein:

the first direction relative to the plurality of acoustic drivers is selected to extend along a direction of maximum acoustic radiation of one of the acoustic drivers of the plurality of acoustic drivers; and

the second direction relative to the plurality of acoustic drivers is perpendicular to the first direction relative to the plurality of acoustic drivers.

18. The method of claim 13, further comprising:

monitor a gravity detector disposed on the casing to determine the orientation of the casing;

providing a first plurality of coefficients to a plurality of filters to cause the plurality of acoustic drivers to be operated to generate destructive interference in the first direction relative to the plurality of acoustic drivers in response to determining that the casing is in the first orientation; and

provide a second plurality of coefficients to the plurality of filters to cause the plurality of acoustic drivers to be operated to generate destructive interference in the second direction relative to the plurality of acoustic drivers in response to determining that the casing is in the second orientation.