US3686471A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System for recording and/or reproducing four channel signals on a record disc
Assignee: Victor Company of Japan Ltd
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Filing: 1970-11-25
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Granted: 1972-08-22
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Expires: 1990-11-25
Abstract
Abstract This system records four channel signals on or reproduces them from a record disc. The four channel signals are combined into sum signals and difference signals, respectively, each composed of two signals. Each difference signal is converted into an angle modulated wave by modulating a carrier from a single oscillator and is multiplexed with each sum signal. The four channel signals picked up from the record disc are reproduced and sounded respectively from four speakers placed at predetermined positions.
Inventors
- 👤 Nobuaki Takahashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 12:46
CPC Classifications
H; H04; H04S; H04S3/00; H04S3/006
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
450 words
A system for recording four channel signals on a record disc, said system comprising a signal source means for supplying four separate channel signals, matrix circuit means for composing a first sum signal and a first difference signal responsive to the first and second channel signals and a second sum signal and a second difference signal responsive to the third and fourth channel signals among the four separate channel signals, single oscillator means for oscillating to provide a signal having a predetermined frequency, frequency divider means operated responsive to the oscillator signal of predetermined frequency for dividing the frequency thereof, means responsive to the output of the frequency divider means for generating a saw-tooth waveform signal, first serrasoid modulator means for anglemodulating said saw-tooth waveform signal with the first difference signal, second serrasoid modulator means for anglemodulating said saw-tooth waveform signal with the second difference signal, first frequency multiplier means for multiplying the frequency of the output signal of the first serrasoid modulator means, second frequency multiplier means for multiplying the frequency of the output signal of the second serrasoid modulator means, first mixer means responsive to the output signal of the first frequency multiplier means and the output signal of the single oscillator means for producing a signal having frequencies equal to the difference between the frequencies of the output signal of the first frequency multiplier means and the predetermined frequency of the single oscillator means, second mixer means responsive to the output signal of the second frequency multiplier means and the output signal of the single oscillator means for producing a signal having frequencies equal to the difference between the frequencies of the output signal of the second frequency multiplier means and the predetermined frequency of the single oscillator means, means whereby the carrier frequencies of the output signals of said first and second mixer means have frequencies in a recordable frequency range of the record disc, the maximum phase angle deviation of the carrier wave of each of the output Signals of said first and second mixer means being between 0.3 and 3 radians and the lower frequency limit of said carrier wave being higher than the upper frequency limit of the first and second sum signals, third mixer means for mixing and multiplexing the first sum signal with the output signal of the first mixer means, fourth mixer means for mixing and multiplexing the second sum signal with the output signal of the second mixer means, and means for simultaneously recording the output signal of the third mixer means on one wall of a single groove of the record disc and the output signal of the fourth mixer means on the other wall of the groove.
Claim 2
Independent Claim
450 words
A system for recording four channel signals on a record disc, said system comprising a signal source means for supplying four separate channel signals, matrix circuit means for composing a first sum signal and a first difference signal responsive to the first and second channel signals and a second sum signal and a second difference signal responsive to the third and fourth channel signals among the four separate channel signals, single oscillator means for oscillating to provide a signal having a predetermined frequency, frequency divider means operated responsive to the oscillator signal of predetermined frequency for dividing the frequency thereof, means responsive to the output of the frequency divider means for generating a saw-tooth waveform signal, first serrasoid modulator means for anglemodulating said saw-tooth waveform signal with the first difference signal, second serrasoid modulator means for anglemodulating said saw-tooth waveform signal with the second difference signal, first frequency multiplier means for multiplying the frequency of the output signal of the first serrasoid modulator means, second frequency multiplier means for multiplying the frequency of the output signal of the second serrasoid modulator means, first mixer means responsive to the output signal of the first frequency multiplier means and the output signal of the single oscillator means for producing a signal having frequencies equal to the difference between the frequencies of the output signal of the first frequency multiplier means and the predetermined frequency of the single oscillator means, second mixer means responsive to the output signal of the second frequency multiplier means and the output signal of the single oscillator means for producing a signal having frequencies equal to the difference between the frequencies of the output signal of the second frequency multiplier means and the predetermined frequency of the single oscillator means, means whereby the carrier frequencies of the output signals of said first and second mixer means have frequencies in a recordable frequency range of the record disc, the maximum phase angle deviation of the carrier wave of each of the output Signals of said first and second mixer means being between 0.3 and 3 radians and the lower frequency limit of said carrier wave being higher than the upper frequency limit of the first and second sum signals, third mixer means for mixing and multiplexing the first sum signal with the output signal of the first mixer means, fourth mixer means for mixing and multiplexing the second sum signal with the output signal of the second mixer means, and means for simultaneously recording the output signal of the third mixer means on one wall of a single groove of the record disc and the output signal of the fourth mixer means on the other wall of the groove.
Claim 3
Independent Claim
259 words
A system for recording four channel signals in a single groove cut on a record disc, said system comprising signal source means for supplying four separate channel signals, matrix circuit means for composing a first sum signal and a first difference signal responsive to the first and second channel signals and also a second sum signal and a second difference signal responsive to the third and fourth channel signals of the four separate channel signals, single oscillator means for generating a carrier wave having a predetermined frequency, first modulator means for angle-modulating said carrier wave with the first difference signal, second modulator means for angle-modulating said carrier wave with the second difference signal, each of said modulator means comprising means whereby the maximum phase angle deviation of said carrier wave is between 0.3 and 3 radians for all frequencies which are included in the four channel signals, the lower frequency limit of the carrier wave in the output of each of said modulator means being higher than the upper frequency limit of the first and second sum signals, first mixer means for mixing and multiplexing the first sum signal with the output signal of the first modulator means, second mixer means for mixing and multiplexing the second sum signal with the output signal of the second modulator means, and means for simultaneously recording the output signal of said first mixer means on one wall of a single groove of the record disc and recording the output signal of said second mixer means on the other wall of the groove.
Claim 4
Independent Claim
259 words
A system for recording four channel signals in a single groove cut on a record disc, said system comprising signal source means for supplying four separate channel signals, matrix circuit means for composing a first sum signal and a first difference signal responsive to the first and second channel signals and also a second sum signal and a second difference signal responsive to the third and fourth channel signals of the four separate channel signals, single oscillator means for generating a carrier wave having a predetermined frequency, first modulator means for angle-modulating said carrier wave with the first difference signal, second modulator means for angle-modulating said carrier wave with the second difference signal, each of said modulator means comprising means whereby the maximum phase angle deviation of said carrier wave is between 0.3 and 3 radians for all frequencies which are included in the four channel signals, the lower frequency limit of the carrier wave in the output of each of said modulator means being higher than the upper frequency limit of the first and second sum signals, first mixer means for mixing and multiplexing the first sum signal with the output signal of the first modulator means, second mixer means for mixing and multiplexing the second sum signal with the output signal of the second modulator means, and means for simultaneously recording the output signal of said first mixer means on one wall of a single groove of the record disc and recording the output signal of said second mixer means on the other wall of the groove.
Claim 5
Dependent Claim
121 words
The recording system as defined in claim 2 wherein said signal source means comprises four microphones which are placed at predetermined distances and positions relative to a sound source for converting the sounds from said sound sources into distance and position dependent electric signals, means responsive to each electric signal generated by each of said microphones for recording said signals as the four channel signals on a magnetic tape while said tape is running at a first running speed, means for reproducing the four channel signals from said magnetic tape while said tape is running at a second running speed which is slower than said first running speed, and means for supplying the reproduced four channel signals to said matrix means.
Claim 6
Dependent Claim
213 words
A system for reproducing the four channel signals which are recorded on the record disc according to claim 2, said system comprising pickup means for generating electrical signals responsive to the signals recorded on the one wall of the groove and electrical signals responsive to the signals recorded on the other wall of the groove, first separator means for separating the first sum signal and the angle modulated signal which is modulated with the first difference signal, second separator means for separating the second sum signal and the angle modulated signal which is modulated with the second difference signal, first demodulator means for demodulating the angle modulated signal separated by the first separator means and thus reproducing the first difference signal, second demodulator means for demodulating the angle modulated signal separated by the second separator means and thus reproducing the second difference signal, second matrix circuit means responsive to the separated first sum signal and the reproduced firSt difference signal for separately reproducing the original first and second channel signals, third matrix circuit means responsive to the separated second sum signal and the reproduced second difference signal for separately reproducing the original third and fourth channel signals, and means comprising four speakers for respectively generating sound responsive to the reproduced four channel signals.
Claim 7
Dependent Claim
67 words
The reproducing system as defined in claim 4 wherein said four speakers are arranged with respect to the listener so that the first speaker is placed at the front and on one side, the second speaker at the rear and on the one side, the third speaker at the front and on the other side, and the fourth speaker at the rear and on the other side.
Claim 8
Dependent Claim
67 words
The reproducing system as defined in claim 4 wherein said four speakers are arranged with respect to the listener so that the first speaker is placed at the front and on one side, the second speaker at the rear and on the other side, the third speaker at the front and on the other side, and the fourth speaker at the rear and on the one side.
Claim 9
Independent Claim
293 words
A system for recording four channel signals on a record disc, said system comprising signal source means for supplying four separate channel signals, matrix circuit means for composing a first sum signal and a first difference signal responsive to the first and second channel signals and a second sum signal and a second difference signal responsive to the third and fourth channel signals among the four separate channel signals, first equalizer means for receiving the first difference signal, second equalizer means for receiving the second difference signal, said first and second equalizer means having a characteristic frequency response which increases in proportion to an increase of frequency at a slope of 6 dB/octave, single oscillator means for generating a carrier wave having a predetermined frequency, first modulator means for frequency modulating said carrier wave responsive to the output signal of the first equalizer means, second modulator means for frequency modulating said carrier wave responsive to the output signal of the second equalizer means, the maximum phase angle deviation of the modulated carrier wave being between 0.3 and 3 radians in each output of said first and second modulator means and the lower frequency limit of said modulated carrier wave being higher than the upper frequency limit of said first and second sum signals, first mixer means for mixing and multiplexing the first sum signal with the output signal of the first modulator means, second mixer means for mixing and multiplexing the second sum signal with the output signal of the second modulator means, and means for simultaneously recording the output signal of said first mixer means on one wall of a single groove of the record disc and the output signal of said second mixer means on the other wall of the groove.
Claim 10
Independent Claim
293 words
A system for recording four channel signals on a record disc, said system comprising signal source means for supplying four separate channel signals, matrix circuit means for composing a first sum signal and a first difference signal responsive to the first and second channel signals and a second sum signal and a second difference signal responsive to the third and fourth channel signals among the four separate channel signals, first equalizer means for receiving the first difference signal, second equalizer means for receiving the second difference signal, said first and second equalizer means having a characteristic frequency response which increases in proportion to an increase of frequency at a slope of 6 dB/octave, single oscillator means for generating a carrier wave having a predetermined frequency, first modulator means for frequency modulating said carrier wave responsive to the output signal of the first equalizer means, second modulator means for frequency modulating said carrier wave responsive to the output signal of the second equalizer means, the maximum phase angle deviation of the modulated carrier wave being between 0.3 and 3 radians in each output of said first and second modulator means and the lower frequency limit of said modulated carrier wave being higher than the upper frequency limit of said first and second sum signals, first mixer means for mixing and multiplexing the first sum signal with the output signal of the first modulator means, second mixer means for mixing and multiplexing the second sum signal with the output signal of the second modulator means, and means for simultaneously recording the output signal of said first mixer means on one wall of a single groove of the record disc and the output signal of said second mixer means on the other wall of the groove.
Claim 11
Dependent Claim
50 words
The recording system as defined in claim 7 wherein said first and second equalizer means respectively have a rising slope characteristic of 6 dB/octave in a frequency range which is higher than a predetermined frequency and a flat characteristic in a frequency range which is lower than said predetermined frequency.
Claim 12
Dependent Claim
33 words
The recording system as defined in claim 8 wherein said predetermined frequency in the first and second equalizer means is selected at a certain frequency within a range of 100 to 2,000 Hz.
Claim 13
Dependent Claim
263 words
A system for reproducing the four channel signals which are recorded on the record disc according to the system of claim 7, said system comprising pickup means for playing back as electrical signals the signals recorded on the one wall of the groove of the record disc and also the signals recorded on the other wall of the groove, first separator means for separating the first sum signal and the frequency modulated signal modulated with the first difference signal, second separator means for separating the second sum signal and the frequency modulated signal modulated with the second difference signal, first demodulator means for demodulating the frequency modulated signal separated by the first separator means and thus reproducing the first difference signal, second demodulator means for demodulating the frequency modulated signal separated by the second separator means and thus reproducing the second difference signal, first equalizer means for receiving the demodulated first difference signal, second equalizer means receiving the demodulated second difference signal, said first and second equalizer means having a characteristic frequency response which decreases in proportion to an increase of frequency at a slope of 6 dB/octave, second matrix circuit means responsive to the separated first sum signal and the output signal of the first equalizer means for separately reproducing the original first and second channel signals, third matrix circuit means responsive to the separated second sum signal and the output signal of the second equalizer means for separately reproducing the original third and fourth channel signals, and means comprising four speakers for respectively reproducing as sound the reproduced four channel signals.
Claim 14
Dependent Claim
50 words
The reproducing system as defined in claim 10 wherein said first and second equalizer means have a falling slope frequency characteristic of 6 dB/octave in a frequency range which is higher than a predetermined frequency and a flat characteristic in a frequency range which is lower than said predetermined frequency.
Claim 15
Dependent Claim
25 words
The reproducing system as defined in claim 11 wherein said predetermined frequency is a selected certain frequency within a range of 100 to 2,000 Hz.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-22 | 1976-02-21 | 1976-08-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-22 | 1980-02-21 | 1980-08-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-22 | 1984-02-21 | 1984-08-22 | $7700.00 | Window Closed / Lapsed |