Patent US2401288A successfully refreshed from Google Patents.
US4245136A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Monitor ampliphones
Assignee: Individual
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Filing: 1978-10-12
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Granted: 1981-01-13
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Expires: 1998-10-12
Abstract
Abstract An improved quadraphonic headphone arrangement in which a first audio signal is coupled to a speaker in each headphone and a second audio signal, usually monaural, is coupled to an amplifier and then to a second speaker in each headphone. Switching means are also provided so that the second speakers may be connected directly to the second audio source without amplification. The headphone is used as a musician's practice aid or for track-making or similar purposes. A prerecorded signal is coupled to the first speakers while the musician's electronic instrument output is coupled through the amplifier to the second set of speakers.
Inventors
- 👤 Robert W. Krauel, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 21:22
CPC Classifications
H; H04; H04R; H04R3/00; H04R3/12
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
121 words
Headphone apparatus for comparing a reference performance to an independent performance of a musical work comprising: right and left earpieces each comprising a generally cup-shaped casing adapted for covering the ears of a listener, first and second speaker means carried within each of said earpieces, coupling means connected to said first speaker means in each earpiece for coupling a first source of audio frequency signals representing said reference performance to said first speaker means, and electronic signal processing means, including amplifier means, having an input adapted for connection to a second source of audio frequency signals representing said independent performance and outputs connected to said second speaker means in each earpiece for coupling said second source to said second speaker means.
Claim 2
Dependent Claim
121 words
Headphone apparatus for comparing a reference performance to an independent performance of a musical work comprising: right and left earpieces each comprising a generally cup-shaped casing adapted for covering the ears of a listener, first and second speaker means carried within each of said earpieces, coupling means connected to said first speaker means in each earpiece for coupling a first source of audio frequency signals representing said reference performance to said first speaker means, and electronic signal processing means, including amplifier means, having an input adapted for connection to a second source of audio frequency signals representing said independent performance and outputs connected to said second speaker means in each earpiece for coupling said second source to said second speaker means.
Claim 3
Dependent Claim
27 words
Headphone apparatus according to claim 1 wherein said coupling means is a plurality of electrical conductors adapted for connection to said first source of audio frequency signals.
Claim 4
Dependent Claim
58 words
Headphone apparatus according to claim 1 wherein said electronic signal processing means further includes switching means for, in a first switch position, coupling said second source directly to said second speaker means, and in a second switch position, coupling said second source to said amplifier means and the output of said amplifier means to said second speaker means.
Claim 5
Dependent Claim
48 words
Headphone apparatus according to claim 3 wherein said electronic signal processing means is mounted within one or both of said right and left earpieces and further including a plurality of electrical conductors connected to said input and adapted for connection to said second source of audio frequency signals.
Claim 6
Dependent Claim
14 words
Apparatus according to claim 4 wherein said electronic amplifier means further includes a battery.
Claim 7
Dependent Claim
18 words
Headphone apparatus according to claim 1 wherein said second speaker means comprises a single speaker in each earpiece.
Claim 8
Dependent Claim
28 words
Headphone apparatus according to claim 6 wherein said electronic amplifier means comprises a single electronic amplifier having an output connected to both speakers comprising said second speaker means.
Claim 9
Dependent Claim
60 words
Headphone apparatus according to claim 1 wherein said first speaker means comprises one speaker in each earpiece, said first source of audio frequency signals is a stereophonic source having outputs for providing a pair of stereophonic signals, and said coupling means is adapted to couple a separate one of the stereophonic signals to each speaker of said first speaker means.
Claim 10
Independent Claim
81 words
A method of using multi-speaker headphones having at least two speakers in each earpiece for comparing a reference performance to an independent performance of a musical work comprising; coupling first audio frequency signals representing said reference performance to a first speaker means in each earpiece of said headphones, and coupling a second audio frequency signal representing said independent performance to second speaker means in each earpiece, whereby a user of said headphones is able to compare said reference and independent performances.
Claim 11
Independent Claim
81 words
A method of using multi-speaker headphones having at least two speakers in each earpiece for comparing a reference performance to an independent performance of a musical work comprising; coupling first audio frequency signals representing said reference performance to a first speaker means in each earpiece of said headphones, and coupling a second audio frequency signal representing said independent performance to second speaker means in each earpiece, whereby a user of said headphones is able to compare said reference and independent performances.
Claim 12
Dependent Claim
21 words
A method according to claim 9 wherein said second audio signal is coupled through an amplifier to said second speaker means.
Claim 13
Dependent Claim
15 words
An improved method according to claim 9 wherein said reference performance is a prerecorded performance.
Claim 14
Dependent Claim
30 words
An improved method according to claim 9 wherein said first speaker means comprises a single speaker in each headphone and said first audio signals comprise a pair of stereophonic signals.
Claim 15
Dependent Claim
19 words
A method according to claim 9 wherein said second audio frequency signal is the output of a musical instrument.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-01-13 | 1984-07-14 | 1985-01-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-01-13 | 1988-07-14 | 1989-01-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-01-13 | 1992-07-14 | 1993-01-13 | $7700.00 | Window Closed / Lapsed |