US3777076A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multi-directional sound system
Assignee: Sansui Electric Co Ltd
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Filing: 1972-07-03
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Granted: 1973-12-04
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Expires: 1992-07-03
Abstract
Abstract A multi-directional sound system for use in the manufacture of matrix four channel stereophono discs comprises an encoder including a plurality of phase shifters for shifting the phases of a plurality of directional input signals from discrete sound sources by angles corresponding to the directions of the sound sources and a matrix circuit for producing two channel signals, and a decoder for decoding the two channel signals for reproducing the directional input signals.
Inventors
- 👤 S Takahashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 14:53
CPC Classifications
H; H04; H04S; H04S3/00; H04S3/02; G; G11; G11B; G11B20/00; G11B20/00992
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
301 words
An encoder system for producing two channel signals suitable for recording on a phono disc from first to fourth directional audio input signals, said encoder system comprising: first to fourth input terminals for receiving said first to fourth audio input signals, respectively; first and second output terminals from which said two channel signals are derived, respectively; first to fourth phase shifter means coupled to said first to fourth input terminals, respectively, said first to fourth phase shifter means being operative to introduce relative phase differences of about +22.5*, +67.5*, -22.5* and -67.5* between said first to fourth audio input signals; means connected in circuit with said first phase shifter means for coupling about 0.92 of said first audio input signal to said first output terminal; means connected in circuit with said first phase shifter means for coupling about 0.38 of said first audio input signal to said second output terminal; means connected in circuit with said Second phase shifter means for coupling about 0.92 of said second audio input signal to said first output terminal; means connected in circuit with said second phase shifter means for coupling about -0.38 of said second audio input signal to said second output terminal; means connected in circuit with said third phase shifter means for coupling about 0.38 of said third audio input signal to said first output terminal; means connected in circuit with said third phase shifter means for coupling about 0.92 of said third audio input signal to said second output terminal; means connected in circuit with said fourth phase shifter means for coupling about -0.38 of said fourth audio input signal to said first output terminal; and means connected in circuit with said fourth phase shifter means for coupling about 0.92 of said fourth audio input signal to said second output terminal.
Claim 2
Dependent Claim
301 words
An encoder system for producing two channel signals suitable for recording on a phono disc from first to fourth directional audio input signals, said encoder system comprising: first to fourth input terminals for receiving said first to fourth audio input signals, respectively; first and second output terminals from which said two channel signals are derived, respectively; first to fourth phase shifter means coupled to said first to fourth input terminals, respectively, said first to fourth phase shifter means being operative to introduce relative phase differences of about +22.5*, +67.5*, -22.5* and -67.5* between said first to fourth audio input signals; means connected in circuit with said first phase shifter means for coupling about 0.92 of said first audio input signal to said first output terminal; means connected in circuit with said first phase shifter means for coupling about 0.38 of said first audio input signal to said second output terminal; means connected in circuit with said Second phase shifter means for coupling about 0.92 of said second audio input signal to said first output terminal; means connected in circuit with said second phase shifter means for coupling about -0.38 of said second audio input signal to said second output terminal; means connected in circuit with said third phase shifter means for coupling about 0.38 of said third audio input signal to said first output terminal; means connected in circuit with said third phase shifter means for coupling about 0.92 of said third audio input signal to said second output terminal; means connected in circuit with said fourth phase shifter means for coupling about -0.38 of said fourth audio input signal to said first output terminal; and means connected in circuit with said fourth phase shifter means for coupling about 0.92 of said fourth audio input signal to said second output terminal.
Claim 3
Dependent Claim
260 words
A decoder for producing first to fourth output signals from first and second channel signals each including four audio signals having predetermined relative amplitude ratios and relative phase differences of about +22.5*, +67.5* -22.5* and -67.5* therebetween, said decoder comprising: first and second input terminals for receiving said first and second channel signals, respectively; first to fourth output terminals from which said four output signals are derived, respectively; first to fourth phase shifter means coupled to said first to fourth output terminals, respectively; means connected to said first input terminal for coupling about 0.92 of said first channel signal to said first phase shifter means; means connected to said first input terminal for coupling about 0.92 of said first channel signal to said second phase shifter means; means connected to said first input terminal for coupling about 0.38 of said first channel signal to said third phase shifter means; means connected to said first input terminal for coupling about -0.38 of said first channel signal to said fourth phase shifter means; means connected to said second input terminal for coupling about 0.38 of said second channel signal to said first phase shifter means; means connected to said second input terminal for coupling about -0.38 of said second channel signal to said second phase shifter means; means connected to said second input terminal for coupling about 0.92 of said second channel signal to said third phase shifter means; and means connected to said second input terminal for coupling about 0.92 of said second channel signal to said fourth phase shifter means.
Claim 4
Dependent Claim
260 words
A decoder for producing first to fourth output signals from first and second channel signals each including four audio signals having predetermined relative amplitude ratios and relative phase differences of about +22.5*, +67.5* -22.5* and -67.5* therebetween, said decoder comprising: first and second input terminals for receiving said first and second channel signals, respectively; first to fourth output terminals from which said four output signals are derived, respectively; first to fourth phase shifter means coupled to said first to fourth output terminals, respectively; means connected to said first input terminal for coupling about 0.92 of said first channel signal to said first phase shifter means; means connected to said first input terminal for coupling about 0.92 of said first channel signal to said second phase shifter means; means connected to said first input terminal for coupling about 0.38 of said first channel signal to said third phase shifter means; means connected to said first input terminal for coupling about -0.38 of said first channel signal to said fourth phase shifter means; means connected to said second input terminal for coupling about 0.38 of said second channel signal to said first phase shifter means; means connected to said second input terminal for coupling about -0.38 of said second channel signal to said second phase shifter means; means connected to said second input terminal for coupling about 0.92 of said second channel signal to said third phase shifter means; and means connected to said second input terminal for coupling about 0.92 of said second channel signal to said fourth phase shifter means.
Claim 5
Dependent Claim
32 words
A decoder according to claim 2 wherein said first to fourth phase shifter means are operative to introduce between input signals thereto relative phase differences of about -22.5*, -67.5*, +22.5* and +67.5*.
Claim 6
Dependent Claim
32 words
A decoder according to claim 2 wherein said first to fourth phase shifter means are operative to introduce between input signals thereto relative phase differences of about 0*, -90*, 0* and 90*.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-12-03 | 1977-06-04 | 1977-12-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-03 | 1981-06-04 | 1981-12-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-03 | 1985-06-04 | 1985-12-04 | $7700.00 | Window Closed / Lapsed |