US3906156A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Signal matrixing for directional reproduction of sound
Assignee: Individual
•
Filing: 1972-09-13
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Granted: 1975-09-16
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Expires: 1992-09-13
Abstract
Abstract Multidirectional sound signals are optimally matrixed to increase the psychoacoustic directional fidelity as compared with prior systems. Four (or more) azimuthally spaced loudspeakers are fed from two transmission channels with very satisfactory directional sensing accuracy and full compatibility with conventional single-channel and two-channel reproduction equipment. Further auxiliary transmission channels may be added to produce a form of discrete-channel capability having even greater azimuthal fidelity than obtained in speaker-identified channels, while at the same time maintaining compatibility both with conventional reproducing equipment and with equipment for the basic two-channel transmission of the invention. The auxiliary channels may be transmitted in a relatively narrow frequency range, thus reducing the total bandwidth requirement for recording or broadcasting as compared with full conventional discrete channels.
Inventors
- 👤 Duane H Cooper
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 23:55
CPC Classifications
H; H04; H04S; H04S3/00; H04S3/02; G; G11; G11B; G11B20/00; G11B20/00992
Claims Analysis
Total Claims: 44
Claim 1
Independent Claim
77 words
A method of producing signals with directional audio information comprising matrixing source signals representative of sounds from different bearing angles theta , each measured from a source reference direction, to form at least three transmission signals, T , T and TT, capable of being re-matrixed for production of presentation signals, each of said transmission signalshaving encoding mixing coefficients substantially corresponding to values of single-variable 360* repetitive functions of said bearing angles theta , said single-variable functions being
Claim 2
Independent Claim
77 words
A method of producing signals with directional audio information comprising matrixing source signals representative of sounds from different bearing angles theta , each measured from a source reference direction, to form at least three transmission signals, T , T and TT, capable of being re-matrixed for production of presentation signals, each of said transmission signalshaving encoding mixing coefficients substantially corresponding to values of single-variable 360* repetitive functions of said bearing angles theta , said single-variable functions being
Claim 3
Dependent Claim
25 words
The method of claim 1 wherein said three transmission signals are formed from any three mutually independent linear combinations of T , T and TT.
Claim 4
Dependent Claim
25 words
The method of claim 1 comprising passing signal TT through a filter to narrow the frequency band thereof relative to the other two transmission signals.
Claim 5
Dependent Claim
28 words
The method of claim 3 comprising shifting the phase of said other transmission signals in amounts equal in frequency characteristic to the phase shifts produced by said filter.
Claim 6
Dependent Claim
20 words
The method of claim 1 wherein there are at least four transmission signals, the fourth transmission signal being formed as:
Claim 7
Dependent Claim
34 words
The method of claim 5 wherein said four transmission signals are formed from any two mutually independent linear combinations of T and T and any two mutually independent linear combinations of TT and TQ.
Claim 8
Dependent Claim
29 words
The method of claim 5 wherein said four transmission signals are formed from four mutually independent linear combinations of T , T , TT and TQ, said combinations being:
Claim 9
Dependent Claim
25 words
The method of claim 5 comprising passing signals TT and TQ through filters to narrow the frequency bands relative to the other two transmission signals.
Claim 10
Dependent Claim
28 words
The method of claim 8 comprising shifting the phase of said other transmission signals in amounts equal in frequency characteristic to the phase shifts produced by said filters.
Claim 11
Dependent Claim
64 words
A recording with directional audio information derived from matrixed source signals representative of sounds from different bearing angles theta , each measured from a source reference direction, to form at least three recorded signals, T , T and TT, each having mixing coefficients substantially corresponding to values of single-variable 360* repetitive functions of said bearing angles theta , said single-variable functions being defined as:
Claim 12
Dependent Claim
64 words
A recording with directional audio information derived from matrixed source signals representative of sounds from different bearing angles theta , each measured from a source reference direction, to form at least three recorded signals, T , T and TT, each having mixing coefficients substantially corresponding to values of single-variable 360* repetitive functions of said bearing angles theta , said single-variable functions being defined as:
Claim 13
Dependent Claim
25 words
The recording of claim 10 wherein said three recorded signals are formed from any three mutually independent linear combinations of T , T and TT.
Claim 14
Dependent Claim
21 words
The recording of claim 10 wherein the recorded signal TT has a substantially narrower frequency band than T and T .
Claim 15
Dependent Claim
20 words
The recording of claim 10 wherein there are at least four recorded signals, the fourth recorded signal being formed as:
Claim 16
Dependent Claim
34 words
The recording of claim 13 wherein said four recorded signals are formed from any two mutually independent linear combinations of T and T and any two mutually independent linear combinations of TT and TQ.
Claim 17
Dependent Claim
31 words
The recording of claim 13 wherein said four recorded signals are formed from four mutually independent linear combinations of T , T , TT and TQ, said combinations being defined by:
Claim 18
Dependent Claim
22 words
The recording of claim 13 wherein said recorded signals TT and TQ have substantially narrower frequency bands than T and T .
Claim 19
Dependent Claim
28 words
The method of claim 2 wherein said three mutually independent linear combinations of T , T and TT are respectively given by TL, TR and TT defined as:
Claim 20
Dependent Claim
31 words
The recording of claim 11 wherein said three mutually independent linear combinations of T , T and TT are respectively given by TL not identical , TR and TT defined as:
Claim 21
Independent Claim
88 words
A method of producing presentation signals from at least three transmission signals, T , T and TT for an array of acoustical transducers distributed at respective bearing angles relative to a presentation reference direction about a listening space, the transmission signals being formed from source signals representative of sounds from different bearing angles theta , each measured from a source reference direction, and having encoded mixing coefficients substantially corresponding to values of single-variable 360* repetitive functions of said bearing angles theta , said single-variable functions being defined as:
Claim 22
Independent Claim
88 words
A method of producing presentation signals from at least three transmission signals, T , T and TT for an array of acoustical transducers distributed at respective bearing angles relative to a presentation reference direction about a listening space, the transmission signals being formed from source signals representative of sounds from different bearing angles theta , each measured from a source reference direction, and having encoded mixing coefficients substantially corresponding to values of single-variable 360* repetitive functions of said bearing angles theta , said single-variable functions being defined as:
Claim 23
Dependent Claim
98 words
The method of producing presentation signals in accordance with claim 19 wherein said transmission signals ar in the form TL, TR and TT defined as: TL 1/2 (T + T ) TR 1/2 (T - T ) TT TT and said method comprises the steps of multiplying each of the transmission signals TL, TR and TT by decoding mixing coefficients and adding the product signals formed thereby substantially in accordance with the relationship defined by Pi 1/2 TL (1 + e j ( /2)) + 1/2 TR (1 - e j ( /2)) + TT ej ( 12).
Claim 24
Independent Claim
78 words
The method of producing presentation signals from at least four transmission signals for an array of acoustical transducers distributed at respective bearing angles relative to a reference direction about a listening space, the transmission signals being formed from matrixed source signals reprsentative of sounds from different bearing angles theta , each measured from a source reference direction, and having encoding mixing coefficients substantially corresponding to values of functions of the bearing angles theta defined by the following relationships:
Claim 25
Independent Claim
78 words
The method of producing presentation signals from at least four transmission signals for an array of acoustical transducers distributed at respective bearing angles relative to a reference direction about a listening space, the transmission signals being formed from matrixed source signals reprsentative of sounds from different bearing angles theta , each measured from a source reference direction, and having encoding mixing coefficients substantially corresponding to values of functions of the bearing angles theta defined by the following relationships:
Claim 26
Dependent Claim
95 words
The method of claim 21 wherein the transmission signals T and T form signals TL and TR according to the following relationships: TL 1/2 (T + T ) TR 1/2 (T - T ) and said method comprises the steps of multiplying each of the signals TL, TR, TT and TQ by decoding mixing coefficients and adding the product signals formed thereby substantially in accordance with the relationship defined by Pi 1/2 TL (1 + e j( /2)) + 1/2 TR (1 - e j( /2)) + TT ej( /2) + TQ e 2j( /2)
Claim 27
Dependent Claim
38 words
The method of claim 19 wherein the signal TT has a substantially narrower frequency range than T and T and each presentation signal is attenuated in the frequency range of these signals to equalize the overall frequency response.
Claim 28
Dependent Claim
39 words
The method of claim 21 wherein the signals TT and TQ have substantially narrower frequency ranges than T and T and each presentation signal is attenuated in the frequency range of these signals to equalize the overall frequency response
Claim 29
Dependent Claim
92 words
Apparatus for the production of signals with directional audio information comprising matrix means for matrixing source signals representative of sounds from different bearing angles theta , each measured from a source reference direction, to form at least three transmission signals, T , T and TT, capable of being re-matrixed for production of presentation signals, said matrix means including means for providing encoding mixing coefficients for each of said transmission signals substantially corresponding to values of single-variable 360 * repetitive functions of said bearing angles theta , said sIngle-variable functions being defined as:
Claim 30
Dependent Claim
92 words
Apparatus for the production of signals with directional audio information comprising matrix means for matrixing source signals representative of sounds from different bearing angles theta , each measured from a source reference direction, to form at least three transmission signals, T , T and TT, capable of being re-matrixed for production of presentation signals, said matrix means including means for providing encoding mixing coefficients for each of said transmission signals substantially corresponding to values of single-variable 360 * repetitive functions of said bearing angles theta , said sIngle-variable functions being defined as:
Claim 31
Dependent Claim
25 words
The apparatus of claim 25 wherein said three transmission signals are formed from any three mutually independent linear combinations of T , T and TT.
Claim 32
Dependent Claim
28 words
The apparatus of claim 26 wherein said three mutually independent linear combinations of T , T and TT are respectively given by TL, TR and TT defined as:
Claim 33
Dependent Claim
26 words
The apparatus of claim 25 comprising a filter responsive to transmission signal TT for narrowing the frequency band thereof relative to the other two transmission signals.
Claim 34
Dependent Claim
32 words
The apparatus of claim 28 comprising phase shifting means to shift the phase of said other transmission signals in amounts equal in frequency characteristic to the phase shifts produced by said filter.
Claim 35
Dependent Claim
24 words
The apparatus of claim 25 wherein said matrix means comprises means for providing at least four transmission signals, the fourth signal being formed as:
Claim 36
Dependent Claim
39 words
The apparatus of claim 30 wherein said matrix means includes means for providing said four transmission signals from any two mutually independent linear combinations of T and T and any two mutually independent linear combinations of TT and TQ.
Claim 37
Dependent Claim
87 words
Apparatus for producing presentation signals from at least three transmission signals, T , T and TT, for an array of acoustical transducers distributed at respective bearing angles relative to a presentation reference direction about a listening space, the transmission signals being formed from source signals representative of sounds from different bearing angles theta , each measured from a source reference direction, and having encoded mixing coefficients substantially corresponding to values of single-variable 360* repetitive functions of said bearing angles theta , said single-variable functions being defined as:
Claim 38
Dependent Claim
87 words
Apparatus for producing presentation signals from at least three transmission signals, T , T and TT, for an array of acoustical transducers distributed at respective bearing angles relative to a presentation reference direction about a listening space, the transmission signals being formed from source signals representative of sounds from different bearing angles theta , each measured from a source reference direction, and having encoded mixing coefficients substantially corresponding to values of single-variable 360* repetitive functions of said bearing angles theta , said single-variable functions being defined as:
Claim 39
Dependent Claim
95 words
Apparatus for producing presentation signals in accordance with claim 32 wherein said transmission signals are in the form TL, TR, and TT defined as: TL 1/2 (T + T ) TR 1/2 (T - T ) TT TT and said apparatus comprises means for multiplying each of the transmission signals TL, TR and TT by decoding mixing coefficients and means for adding the product signals formed thereby substantially in accordance with the relationship defined by Pi 1/2 TL (1 + e j( /2)) + 1/2 TR (1 - e j( /2)) + TT ej( /2)
Claim 40
Dependent Claim
77 words
Apparatus for producing presentation signals from at least four trasmission signals for an array of acoustical transducers distributed at respective bearing angles relative to a reference direction about a listening space, the transmission signals being formed from matrixed source signals representative of sounds from different bearing angles theta , each measured from a source reference direction, and having encoding mixing coefficients substantially corresponding to values of functions of the bearing angles theta defined by the following relationships:
Claim 41
Dependent Claim
77 words
Apparatus for producing presentation signals from at least four trasmission signals for an array of acoustical transducers distributed at respective bearing angles relative to a reference direction about a listening space, the transmission signals being formed from matrixed source signals representative of sounds from different bearing angles theta , each measured from a source reference direction, and having encoding mixing coefficients substantially corresponding to values of functions of the bearing angles theta defined by the following relationships:
Claim 42
Dependent Claim
100 words
The apparatus of claim 34 wherein the transmission signals T and T form signals TL and TR according to the following relationships: TL 1/2 (T + T ) TR 1/2 (T - T ) and said appartus comprises means for multiplying each of the signals TL, TR, TT and TQ by decoding mixing coefficients and means for adding the product signals formed thereby substantially in accordance with the relationship defined by Pi 1/2 TL (1 + e j ( /2)) + 1/2 TR (1 - e j ( /2)) + TT ej ( /2) + TQ e 2j( to /2)
Claim 43
Dependent Claim
41 words
The apparatus of claim 32 comprising means for substantially narrowing the frequency range of signAl TT relative to T and T and means for attenuating each presentation signal in the frequency range of these signals to equalize the overall frequency response.
Claim 44
Dependent Claim
43 words
The apparatus of claim 34 comprising means for substantially narrowing the frequency ranges of signals TT and TQ relative to T and T and means for attenuating each presentation signal in the frequency range of these signals to equalize the overall frequency response.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-09-15 | 1979-03-17 | 1979-09-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-15 | 1983-03-17 | 1983-09-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-15 | 1987-03-17 | 1987-09-16 | $7700.00 | Window Closed / Lapsed |