US3646574A
Expired / Lapsed
US
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Compatible stereo generator
Assignee: Individual
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Filing: 1970-05-25
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Granted: 1972-02-29
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Expires: 1990-05-25
Abstract
Abstract This invention relates to an instrument incorporating an otherwise independent pair of wide band unity gain amplifier chains of novel configuration providing in the several stages of each chain the capability of and means for shifting the phase of signals from stereophonic signal sources applied to each chain. The phase shift capability of one channel is over the range of zero phase shift related to the phase of the input signal through + 90* and in the other channel over a range of from zero phase shift related to the phase of the input signal through - 90*. The wide band phase shift networks are an element in the implementation of a means to apply the discovery disclosed in this invention that if the signal output of each respectively, of a pair of related stereophonic signal channels is applied to one, respectively, of said amplifier chains, one of the channels containing signals identified as A+ C, and the other containing signals identified as B+ C (the C-components of the signals being common to both channels) and the signal of the first channel shifted in phase + 60* while that in the second channel is shifted in phase - 60* (the difference between the two being a total of 120* centered about a zero input reference phase) then the summation of the phase shifted signals from the two channels will result in an output (summed) signal of A+ B+ C, whereas by prior art techniques the summation or mixing of two stereophonic channels produces a resultant A+ B+2C.
Inventors
- 👤 Howard S Holzer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:04
CPC Classifications
H; H04; H04S; H04S3/00
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
175 words
A compatible stereophonic signal generator operable from a pair of stereophonically related signal sources wherein each of said pair of sources provides a common signal component, said generator comprising: a first cascade of phase-shift audio amplifiers for wide band phase shifting the common signal component from one of said signal sources, said first cascade having connected therein adjustable resistor capacitor networks adapted to vary the phase of signals applied thereto over a predetermined range of frequencies; a second cascade of phase shift amplifiers for wide band phase shifting the common signal component from the other of said signal sources, said second cascade having connected therein adjustable resistor capacitor networks adapted to vary the phase of signals applied thereto over said predetermined range of frequencies; said first and second cascades of phase shift amplifiers maintaining a substantially constant phase difference between the phase shifted common signal components, whereby upon being combined for monophonic reproduction, said phase shifted common signal components exhibit a combined signal magnitude less than the sum of the individual common signal component magnitudes.
Claim 2
Dependent Claim
175 words
A compatible stereophonic signal generator operable from a pair of stereophonically related signal sources wherein each of said pair of sources provides a common signal component, said generator comprising: a first cascade of phase-shift audio amplifiers for wide band phase shifting the common signal component from one of said signal sources, said first cascade having connected therein adjustable resistor capacitor networks adapted to vary the phase of signals applied thereto over a predetermined range of frequencies; a second cascade of phase shift amplifiers for wide band phase shifting the common signal component from the other of said signal sources, said second cascade having connected therein adjustable resistor capacitor networks adapted to vary the phase of signals applied thereto over said predetermined range of frequencies; said first and second cascades of phase shift amplifiers maintaining a substantially constant phase difference between the phase shifted common signal components, whereby upon being combined for monophonic reproduction, said phase shifted common signal components exhibit a combined signal magnitude less than the sum of the individual common signal component magnitudes.
Claim 3
Dependent Claim
12 words
The signal generator of claim 1 wherein said phase difference is 90*.
Claim 4
Dependent Claim
12 words
The signal generator of claim 1 wherein said phase difference is 120*.
Claim 5
Dependent Claim
18 words
The signal generator of claim 1 wherein each cascade of phase shift amplifiers comprises three phase shift amplifiers.
Claim 6
Dependent Claim
35 words
The signal generator of claim 1 wherein the frequency ranges for the respective cascade phase shift amplifiers are set for approximately 30 to 300 Hz., 300 to 3,000 Hz. and 3,000 to 30,000 Hz., respectively.
Claim 7
Dependent Claim
51 words
The signal generator of claim 1 wherein for each cascade all the resistors of said adjustable, resistor capacitor, phase shift networks include variable portions, said generator further including a common shaft with the variable portions being connected to said shaft so as to be commonly adjustable with a single manual operation.
Claim 8
Dependent Claim
220 words
A compatible stereophonic signal generator operable from a pair of stereophonically related audio signal sources, each of the pair having at least a signal component common to both said sources, said generator comprising: a first wide band phase shift generator having an input circuit, a first cascade of phase shift amplifiers connected to said input circuit, each of said amplifiers in said first cascade having connected therein adjustable resistor capacitor, phase shift networks adapted to vary the phase of signals applied thereto over a predetermined range of frequencies; a second wide band phase shift generator having an input circuit, a second cascade of phase shift amplifiers connected to said input circuit, each of said amplifiers in said second cascade having connected therein adjustable resistor capacitor, phase shift networks adapted to vary the phase of signals applied thereto over the same predetermined range of frequencies as defined for said first phase shift generator; said first and second wide band phase shift generators producing respective phase shifted signals which differ in relative phase by a substantially constant phase difference; said input circuit of said first wide band phase shift generator being connected to one of said pair of signal sources; said input circuit of said second wide band phase shift generator being connected to the other of the pair of signal sources.
Claim 9
Dependent Claim
220 words
A compatible stereophonic signal generator operable from a pair of stereophonically related audio signal sources, each of the pair having at least a signal component common to both said sources, said generator comprising: a first wide band phase shift generator having an input circuit, a first cascade of phase shift amplifiers connected to said input circuit, each of said amplifiers in said first cascade having connected therein adjustable resistor capacitor, phase shift networks adapted to vary the phase of signals applied thereto over a predetermined range of frequencies; a second wide band phase shift generator having an input circuit, a second cascade of phase shift amplifiers connected to said input circuit, each of said amplifiers in said second cascade having connected therein adjustable resistor capacitor, phase shift networks adapted to vary the phase of signals applied thereto over the same predetermined range of frequencies as defined for said first phase shift generator; said first and second wide band phase shift generators producing respective phase shifted signals which differ in relative phase by a substantially constant phase difference; said input circuit of said first wide band phase shift generator being connected to one of said pair of signal sources; said input circuit of said second wide band phase shift generator being connected to the other of the pair of signal sources.
Claim 10
Dependent Claim
33 words
The signal generator of claim 7 wherein said first and second wide band phase shift generators shift the phase of said common signal components by equal and opposite amounts respectively independently of frequency.
Claim 11
Dependent Claim
14 words
The signal generator of claim 7 wherein said amounts are +45* and -45*, respectively.
Claim 12
Dependent Claim
14 words
The signal generator of claim 7 wherein said amounts are +60* and -60*, respectively.
Claim 13
Independent Claim
117 words
The method of producing compatible two-channel stereophonic signals from first and second stereophonically related signals each containing at least a common signal component, said method comprising the steps of: phase shifting the common signal component of said first signal to provide a first phase shifted common signal component; phase shifting the common signal component of said second signal to provide a second phase shifted common signal component differing in phase from said first phase shifted common signal component by a substantially constant phase angle; and combining said phase shifted common signal components, for monophonic reproduction, to result in a combined component having an amplitude less than the sum of the amplitudes of the individual common signal components.
Claim 14
Independent Claim
117 words
The method of producing compatible two-channel stereophonic signals from first and second stereophonically related signals each containing at least a common signal component, said method comprising the steps of: phase shifting the common signal component of said first signal to provide a first phase shifted common signal component; phase shifting the common signal component of said second signal to provide a second phase shifted common signal component differing in phase from said first phase shifted common signal component by a substantially constant phase angle; and combining said phase shifted common signal components, for monophonic reproduction, to result in a combined component having an amplitude less than the sum of the amplitudes of the individual common signal components.
Claim 15
Dependent Claim
23 words
In the method defined in claim 11, the additional step of applying said first and second phase shifted components to respective impedance-matching networks.
Claim 16
Dependent Claim
52 words
In the method defined in claim 11, the additional step of combining said first and second phase shifted common signal components in a mixing arrangement, whereby a resultant summed common signal is produced which retains substantially the original composition obtained in the initial performance from which said stereophonic related signals were derived.
Claim 17
Independent Claim
187 words
The method of producing compatible two-channel stereophonic signals from first and second stereophonically related signals, said first and second related signals containing, respectively, components A+ B and B+ C wherein the C signal components are common, said method comprising the steps of: applying the A+ C component to a first phase-shifting network; applying the B+ C component to a second phase-shifting network; phase shifting the A+ C component applied to the first phase shift network over a predetermined phase angle to provide a phase shifted A+ C component; phase shifting the B+ C component applied to the second phase-shift network to provide a phase shifted B+ C component, the phase of the C component in the B+ C phase shifted component differing from the phase of the C component in the A+ C phase shifted component by a substantially constant phase angle; and so combining said A+ C and said B+ C components as to provide a compatible stereophonic signal wherein said C component in the combined signal is less than the algebraic sum of the C components in said A+ C and said B+ C components.
Claim 18
Independent Claim
187 words
The method of producing compatible two-channel stereophonic signals from first and second stereophonically related signals, said first and second related signals containing, respectively, components A+ B and B+ C wherein the C signal components are common, said method comprising the steps of: applying the A+ C component to a first phase-shifting network; applying the B+ C component to a second phase-shifting network; phase shifting the A+ C component applied to the first phase shift network over a predetermined phase angle to provide a phase shifted A+ C component; phase shifting the B+ C component applied to the second phase-shift network to provide a phase shifted B+ C component, the phase of the C component in the B+ C phase shifted component differing from the phase of the C component in the A+ C phase shifted component by a substantially constant phase angle; and so combining said A+ C and said B+ C components as to provide a compatible stereophonic signal wherein said C component in the combined signal is less than the algebraic sum of the C components in said A+ C and said B+ C components.
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) | 1975-02-28 | 1975-08-30 | 1976-02-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-28 | 1979-08-30 | 1980-02-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-28 | 1983-08-30 | 1984-02-29 | $7700.00 | Window Closed / Lapsed |