Patent US3684835A successfully refreshed from Google Patents.
US3684835A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Four channel stereo synthesizer
Assignee: DELANTONI JOHN H
•
Filing: 1970-07-29
•
Granted: 1972-08-15
•
Expires: 1990-07-29
Abstract
Abstract A stereo synthesizer according to which a four-channel ''''surround stereo'''' is developed from either two-channel or single-channel sources. The system performs a number of transformations on the source material, and the resulting signals are reproduced through two sets of loudspeakers, one set of these loudspeakers being located in front of the listener and the other set of loudspeakers being located behind the listener. As a consequence if this arrangement, the listener is afforded a sense of space and dimension which is superior to the sensation produced through one or two loudspeakers.
Inventors
- 👤 Robert Arnold Orban
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 21:36
CPC Classifications
H; H04; H04S; H04S5/00; H04S5/02
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
163 words
A multi-channel stereo synthesizer apparatus for providing an acoustic output which completely surrounds a listener and creates a sense of space comprising: a first group of sound reproducers in a first location adjacent the listener, a second group of sound reproducers in a location adjacent said listener and opposite said first location, means for supplying stereophonically related signals to said first group of sound reproducers, means for supplying signals, different from said stereophonically related signals, to said second group of sound reproducers including a. a pair of independent channels having their outputs connected to said second group of sound reproducers, b. means for providing monophonic sound signals at the inputs to each of said channels, c. a quadrature generator connected in one of said pair of channels, said quadrature generator including two all-pass networks having outputs differing in phase by approximately 90* at frequencies from 20 - 20,000 Hz, said outputs being connected to different ones of said second group of sound reproducers.
Claim 2
Dependent Claim
163 words
A multi-channel stereo synthesizer apparatus for providing an acoustic output which completely surrounds a listener and creates a sense of space comprising: a first group of sound reproducers in a first location adjacent the listener, a second group of sound reproducers in a location adjacent said listener and opposite said first location, means for supplying stereophonically related signals to said first group of sound reproducers, means for supplying signals, different from said stereophonically related signals, to said second group of sound reproducers including a. a pair of independent channels having their outputs connected to said second group of sound reproducers, b. means for providing monophonic sound signals at the inputs to each of said channels, c. a quadrature generator connected in one of said pair of channels, said quadrature generator including two all-pass networks having outputs differing in phase by approximately 90* at frequencies from 20 - 20,000 Hz, said outputs being connected to different ones of said second group of sound reproducers.
Claim 3
Dependent Claim
21 words
Apparatus as defined in claim 1, further including a reverberation generator connected in the other one of said pair of channels.
Claim 4
Dependent Claim
63 words
Apparatus as defined in claim 1, further including a stereo synthesizer in said other channel, said stereo synthesizer having two outputs and a single input, the signals from said input being processed such that direct and delayed signals are combined so as to provide reinforcement thereof at one of the outputs and opposition thereof at the other output as a function of frequency.
Claim 5
Dependent Claim
63 words
Apparatus as defined in claim 3, further including a summing network in each of said channels, one of the outputs of said stereo synthesizer and of said quadrature generator being directly connected to the summing network in said one channel, and the other output of said stereo synthesizer and of said quadrature generator being connected to the summing network in the other channel.
References Cited (Backward Citations)
US2819342A
Cited
US2768237A
Cited
US2845491A
Cited
US3067287A
Cited
US3087988A
Cited
US3214519A
Cited
US3478167A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-15 | 1976-02-14 | 1976-08-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-15 | 1980-02-14 | 1980-08-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-15 | 1984-02-14 | 1984-08-15 | $7700.00 | Window Closed / Lapsed |