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US3609240A
Expired / Lapsed
US
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Stereophonic headphones
Assignee: IND PATENT DEV CORP
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Filing: 1970-03-18
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Granted: 1971-09-28
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Expires: 1990-03-18
Abstract
Abstract Stereophonic headphones mount pairs of audio transducers (speakers) on an opposing front to back axis relative to the head of a listener to create a greater panorama of sound.
Inventors
- 👤 Jon S Fixler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 19:18
CPC Classifications
H; H04; H04R; H04R1/00; H04R1/10; H04R1/1058; H04R1/1075; H04R1/1008; H04R2205/00; H04R2205/022; H04R5/00; H04R5/033
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
122 words
Stereophonic headphones for a four channel system comprising a support for retaining first and second enclosures in position over the ears of a listener, a first enclosure and a second enclosure, each enclosure having an opening for the emission of sound into the ear of a listener, each said opening being positioned in the enclosure to face one of the ears of a listener, at least two audio transducers in each enclosure for transducing electronic signals into sound, said two audio transducers being mounted on a common sound emitting axis, the axis defined by said transducers in each enclosure being in a front-back direction relative to the head of a listener when the enclosures are mounted over the ears of a listener.
Claim 2
Dependent Claim
122 words
Stereophonic headphones for a four channel system comprising a support for retaining first and second enclosures in position over the ears of a listener, a first enclosure and a second enclosure, each enclosure having an opening for the emission of sound into the ear of a listener, each said opening being positioned in the enclosure to face one of the ears of a listener, at least two audio transducers in each enclosure for transducing electronic signals into sound, said two audio transducers being mounted on a common sound emitting axis, the axis defined by said transducers in each enclosure being in a front-back direction relative to the head of a listener when the enclosures are mounted over the ears of a listener.
Claim 3
Dependent Claim
25 words
Stereophonic headphones for a four channel system in accordance with claim 1 wherein said speakers are mounted in facing sound emitting relation along said axis.
Claim 4
Dependent Claim
26 words
Stereophonic headphones for a four channel system in accordance with claim 1 wherein said transducers are mounted to emit sound in opposite directions along said axis.
Claim 5
Dependent Claim
28 words
Stereophonic headphones for a four channel system in accordance with claim 1 wherein means are provided within said enclosure to enhance the stereo separation of said audio transducers.
Claim 6
Dependent Claim
22 words
Stereophonic headphones for a four channel system in accordance with claim 4 wherein said means for enhancing the stereo separation is adjustable.
Claim 7
Dependent Claim
19 words
Stereophonic headphones for a four channel system in accordance with claim 5 wherein said means is a cone-shaped, membrane.
Claim 8
Dependent Claim
68 words
Stereophonic headphones for a four channel system comprising at least two pairs of audio transducers, one pair of audio transducers in each headphone, each transducer in a pair being mounted in sound-opposing relation, the axis defined by said opposing transducers in each pair being in a front to back direction relative to the head of a listener when the headphones are mounted over the ear of a listener.
Claim 9
Dependent Claim
68 words
Stereophonic headphones for a four channel system comprising at least two pairs of audio transducers, one pair of audio transducers in each headphone, each transducer in a pair being mounted in sound-opposing relation, the axis defined by said opposing transducers in each pair being in a front to back direction relative to the head of a listener when the headphones are mounted over the ear of a listener.
References Cited (Backward Citations)
US2846521A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-09-27 | 1975-03-29 | 1975-09-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-27 | 1979-03-29 | 1979-09-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-27 | 1983-03-29 | 1983-09-28 | $7700.00 | Window Closed / Lapsed |