Electroacoustical transducing with low frequency augmenting devices

• US 7,676,047 B2
• Filed: 03/07/2003
• Issued: 03/09/2010
• Est. Priority Date: 12/03/2002
• Status: Expired due to Fees

• Current Assignee: Bose Corporation
• Original Assignee: Bose Corporation
• Inventors: Aylward, J. Richard, Barker, Charles R. III
• Primary Examiner(s): Mei; Xu
• Assistant Examiner(s): KURR, JASON RICHARD
• Application Number:
  US10/383,697
• Publication Number:
  US 20040105559A1
• Time in Patent Office: 2,559 Days
• Field of Search: 381/387, 381/338, 381/351, 381/342, 381/334, 381/335, 381/349, 381/97, 381/98, 381/1, 381/17, 381/18, 381/345, 181/148, 181/156, 181/199
• US Class Current: 381/97
• CPC Class Codes: A63F 2300/6063 for sound processing
• CPC Class Codes: H03G 5/165 Equalizers; Volume or gain control in limited frequency bands
• 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 1/26 Spatial arrangements of separate transducers responsive to two or more frequency ranges
• CPC Class Codes: H04R 1/2819 for loudspeaker transducers
• CPC Class Codes: H04R 1/2857 for loudspeaker transducers
• 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 2499/13 Acoustic transducers and sound field adaptation in vehicles
• CPC Class Codes: H04R 5/02 Spatial or constructional arrangements of loudspeakers
• CPC Class Codes: H04R 9/063 using a plurality of acoustic drivers H04R1/24 and H04R1/403 take precedence
• CPC Class Codes: H04S 1/002 Non-adaptive circuits, e.g. manually adjustable or static, for enhancing the sound image or the spatial distribution control circuits for electronic adaptation of the sound field H04S7/30
• 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 3/00 Systems employing more than two channels, e.g. quadraphonic H04S5/00, H04S7/00 take precedence
• CPC Class Codes: H04S 3/002 Non-adaptive circuits, e.g. manually adjustable or static, for enhancing the sound image or the spatial distribution control circuits for electronic adaptation of the sound field H04S7/30

Abstract

A method for processing a multichannel audio signal. The method includes mounting electroacoustical transducers in a low frequency augmenting device. The electroacoustical transducers radiate different high frequency acoustic energy and common low frequency acoustic energy. The transducers may be part of directional arrays. The method is applied to multimedia entertainment devices.

Claims

1. An electroacoustical device, comprising:

a source of a first input signal having bass and high frequency spectral bands,

a first directional array comprising a first electroacoustical transducer and a second electroacoustical transducer operative in a substantially overlapping frequency range;

first signal processing circuitry coupled to said first source and said first and second electroacoustical transducers constructed and arranged to process a high frequency spectral band of said first input signal to provide a first processed high frequency signal to the first electroacoustical transducer and a second processed high frequency signal to the second electroacoustical transducer to cause radiation from the first electroacoustical transducer and radiation from the second electroacoustical transducer to destructively interfere more in some directions than in other directions to cause the first directional array to directionally radiate the high frequency spectral band and to provide the bass frequency spectral band of the first input signal to the first electroacoustical transducer and the second electroacoustical transducer,

a low frequency augmenting structure having an interior and an exterior,

and first and second electroacoustical transducers each having first and second radiating surfaces,

said first radiating surfaces facing a surrounding environment and said second radiating surfaces facing said low frequency augmenting structure interior.

2. An electroacoustical device in accordance with claim 1, further comprising:

a second source of a second input signal having bass and high frequency spectral bands

a second directional array comprising a third electroacoustical transducer and a fourth electroacoustical transducer operative in a substantially overlapping frequency range each comprising a first radiating surface and a second radiating surface;

second signal processing circuitry coupled to said first and second sources and said third and fourth electroacoustical transducers constructed and arranged to process the high frequency spectral band of said second input signal to provide a third processed high frequency signal to the third electroacoustical transducer and a fourth processed high frequency signal to the fourth electroacoustical transducer so that radiation from the third electroacoustical transducer and radiation from the fourth electroacoustical transducer destructively interfere more in some directions than in other directions and to provide,

the bass frequency spectral band of the first input signal and the bass frequency of the second input signal to provide a combined bass signal to the first, second, third and fourth electroacoustical transducers,

so that the first radiating surfaces face said surrounding environment and the second radiating surfaces face said low frequency augmenting structure interior.

3. An electroacoustical device in accordance with claim 1, wherein said low frequency augmenting device comprises one of an acoustical waveguide and a ported enclosure.

4. An electroacoustical device in accordance with claim 1, wherein the signal processing for processing the high frequency spectral band of the first input signal comprises one or more of a phase shifter, a time delay, and a polarity inversion.

5. A method for operating a multimedia entertainment device having an audio system, said multimedia entertainment device including an associated listening space, said method comprising:

radiating directionally toward said listening space, by a first loudspeaker array comprising a first plurality of electroacoustical transducers operating in a substantially overlapping frequency range, sound waves corresponding to a first audio channel high frequency spectral band, said first audio channel high frequency spectral band including frequencies with corresponding wavelengths that are greater than the diameter of radiating surfaces of said plurality of electroacoustical transducers, the radiating directionally toward the listening space by the first loudspeaker array comprising processing the first audio channel high frequency spectral band to provide a first audio channel high frequency first portion and a first audio channel high frequency second portion and transmitting the first audio channel high frequency first portion to one of the first plurality of electroacoustical transducers and the first audio channel high frequency second portion to another of the first plurality of electroacoustical transducers so that radiation from the one of the first plurality of electroacoustical transducers and radiation from the another of the first plurality of electroacoustical transducers destructively interfere more in some directions than in other directions;

radiating directionally toward said listening space, by a second loudspeaker array, sound waves corresponding to a second audio channel high frequency portion, the radiating directionally toward the listening space by the second loudspeaker array comprising processing the second audio channel high frequency spectral band to provide a second audio channel high frequency first portion and a second audio channel high frequency second portion and transmitting the second audio channel high frequency first portion to one of the second plurality of electroacoustical transducers and the first audio channel high frequency second portion to another of the first plurality of electroacoustical transducers so that radiation from the one of the first plurality of electroacoustical transducers and radiation from the another of the first plurality of electroacoustical transducers destructively interfere more in some directions than in other directions;

combining the bass spectral band of the first audio channel and the bass spectral band of the second audio channel to provide a combined bass signal; and

radiating, by said first loudspeaker array and said second loudspeaker array, sound waves corresponding to the combined bass signal into a bass frequency augmenting device.

6. A method for operating a multimedia entertainment device in accordance with claim 5 wherein said multimedia entertainment device is a video game.

7. A method for operating a multimedia entertainment device in accordance with claim 5, wherein said multimedia entertainment device is a gambling machine.

8. A method in accordance with claim 5, said second loudspeaker array comprising electroacoustical transducers operating in a substantially overlapping frequency range, said second audio channel high frequency portion including frequencies with corresponding wavelengths that are greater than the diameter of the radiating surfaces of said second loudspeaker array electroacoustical transducers.

9. A method in accordance with claim 5, wherein the processing the first audio channel high frequency spectral band comprises one or more of phase shifting, time delaying, and polarity inverting.