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1971-02-05 |
1974-01-22 |
Sansui Electric Co |
Quadrasonic sound system for two channel transmission
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1971-02-24 |
1974-01-08 |
Columbia Broadcasting Syst Inc |
Decoders for quadruphonic sound utilizing wave matching logic
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1971-06-23 |
1976-06-29 |
Cbs Inc. |
Logic for matrix systems for reproducing quadraphonic sound
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1971-07-08 |
1974-08-20 |
Matsushita Electric Ind Co Ltd |
Circuit for mixing four audio input signals to produce four audio output signals
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JPS5213082B1
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*
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1971-07-19 |
1977-04-12 |
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GB1398786A
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1971-08-06 |
1975-06-25 |
Sony Corp |
Multisignal transmission apparatus
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1971-09-01 |
1974-02-26 |
Columbia Broadcasting Syst Inc |
Four channel decoder with improved gain control
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1971-10-07 |
1974-07-16 |
Pioneer Electronic Corp |
Magnetic head and simulated four-channel stereo system
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1971-10-19 |
1973-11-13 |
Motorola Inc |
Gain modified multi-channel audio system
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1971-12-30 |
1974-01-01 |
Sansui Electric Co |
Decoder for use in matrix four-channel system
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JPS5240563B2
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1972-03-07 |
1977-10-13 |
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JPS5228361B2
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1972-03-09 |
1977-07-26 |
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JPS5317283B2
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*
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1973-03-07 |
1978-06-07 |
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GB1522599A
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1974-11-16 |
1978-08-23 |
Dolby Laboratories Inc |
Centre channel derivation for stereophonic cinema sound
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1975-09-25 |
1977-04-19 |
Clifford H. Moulton |
Decoder for quadraphonic playback
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1975-10-10 |
1977-02-01 |
Yudin Industries, Inc. |
Audio signal processing apparatus
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1980-03-04 |
1984-10-02 |
Polaroid Corporation |
Method and apparatus for controlling exposure by selective use of blocking visible filter
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1981-08-19 |
1985-07-30 |
John C. Bogue |
Automatic dimension control for a directional enhancement system
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1981-08-27 |
1985-06-25 |
John C. Bogue |
Variable rate and variable limit dimension controls for a directional enhancement system
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1985-03-07 |
1989-01-17 |
Dolby Laboratories Licensing Corporation |
Variable matrix decoder
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1985-03-07 |
1991-09-03 |
Dolby Laboratories Licensing Corporation |
Variable matrix decoder with three output channels
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1990-06-08 |
1996-04-02 |
Harman International Industries, Inc. |
Surround sound processor with improved control voltage generator
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1990-06-08 |
1997-09-09 |
Harman International Industries, Inc. |
Six-axis surround sound processor with automatic balancing and calibration
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1990-06-08 |
1994-08-16 |
Fosgate James W |
Apparatus for enhancing monophonic audio signals using phase shifters
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1990-06-08 |
1994-03-15 |
Fosgate James W |
Control voltage generator for surround sound processor
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1990-06-08 |
1992-12-15 |
Fosgate James W |
Surround processor
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2000-02-22 |
2005-08-02 |
Board Of Trustees Operating Michigan State University |
Process for high fidelity sound recording and reproduction of musical sound
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2013-05-30 |
2015-04-29 |
Egils Ranga |
An optimised three speaker stereo sound system
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2015-03-23 |
2017-03-16 |
Eric Jay Alexander |
Inversion Speaker and Headphone for Music Production
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