GB1497394A - Recording and reproduction of audio signals - Google Patents
Recording and reproduction of audio signalsInfo
- Publication number
- GB1497394A GB1497394A GB294774A GB294774A GB1497394A GB 1497394 A GB1497394 A GB 1497394A GB 294774 A GB294774 A GB 294774A GB 294774 A GB294774 A GB 294774A GB 1497394 A GB1497394 A GB 1497394A
- Authority
- GB
- United Kingdom
- Prior art keywords
- recording
- channel
- frequency
- signals
- reproduction
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04S—STEREOPHONIC SYSTEMS
- H04S3/00—Systems employing more than two channels, e.g. quadraphonic
- H04S3/006—Systems employing more than two channels, e.g. quadraphonic in which a plurality of audio signals are transformed in a combination of audio signals and modulated signals, e.g. CD-4 systems
Landscapes
- Engineering & Computer Science (AREA)
- Multimedia (AREA)
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Signal Processing (AREA)
- Signal Processing For Digital Recording And Reproducing (AREA)
Abstract
1497394 Recording and playback EMI Ltd 17 Jan 1975 [22 Jan 1974] 02947/74 Heading G5R [Also in Division H4] In a system for recording multichannel audio information a first channel signal L frequency modulates a carrier which is recorded in a first recording channel while a second channel signal R is inverted at 4, and frequency modulates a carrier which is recorded in a second recording channel. On reproduction from the recording the channel signals are demodulated at 8 and 9, the second channel signal is inverted, at 10, to restore its initial phase and the two channel signals are separated by filters 14 to 17, into components above and below 200Hz. The low frequencies of the two channels are combined, at 18, in the ratio 0À5 to 0À5 and the combined signal added to each of the high frequency channel signals, at 19 and 20, to provide two output signals, each containing the respective high frequency portion and a common low frequency portion, in which low frequency rumble, introduced into the channel signals by the mechanics of the recording process, has been cancelled. The loss of information by combining the low frequency components is negligible since the low frequencies contain negligible directional information.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB294774A GB1497394A (en) | 1975-01-17 | 1975-01-17 | Recording and reproduction of audio signals |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB294774A GB1497394A (en) | 1975-01-17 | 1975-01-17 | Recording and reproduction of audio signals |
Publications (1)
Publication Number | Publication Date |
---|---|
GB1497394A true GB1497394A (en) | 1978-01-12 |
Family
ID=9749054
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB294774A Expired GB1497394A (en) | 1975-01-17 | 1975-01-17 | Recording and reproduction of audio signals |
Country Status (1)
Country | Link |
---|---|
GB (1) | GB1497394A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2329747A (en) * | 1997-09-25 | 1999-03-31 | Samsung Electronics Co Ltd | Apparatus for recording stereophonic sound |
-
1975
- 1975-01-17 GB GB294774A patent/GB1497394A/en not_active Expired
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2329747A (en) * | 1997-09-25 | 1999-03-31 | Samsung Electronics Co Ltd | Apparatus for recording stereophonic sound |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
GB1372496A (en) | Editing system | |
GB1506087A (en) | Colour video signal recording and/or reproducing system | |
GB1528323A (en) | Colour-picture/multichannel-sound record and recording/playback apparatus | |
AU2699177A (en) | Video signal recording/reproduction | |
AU2668577A (en) | Video signal recording/reproduction | |
KR900013460A (en) | How to record and play | |
AU513808B2 (en) | Playback apparatus for reproducing television signals | |
JPS5797281A (en) | Magnetic reproducing device for video signal | |
GB1497394A (en) | Recording and reproduction of audio signals | |
JPS55163613A (en) | Aural signal recording/reproducing system | |
GB1478339A (en) | Multiple track record replay | |
EP0308775A3 (en) | Magnetic recording and reproducing apparatus | |
GB1427896A (en) | Power supply circuits for combined audio systems | |
JPS57191811A (en) | Recording and reproducing device for sound multiplex video signal | |
GB1384328A (en) | Method for storing signals on a carrier and a carrier therefor | |
GB1403343A (en) | Signal synthesizing system adaptable for discrete four-channel sound reproducing system and matrix four-chennel sound reproducing system | |
JPS5764327A (en) | Pilot signal recording and reproducing system | |
JPS5433009A (en) | Tape recorder | |
JPS5417709A (en) | Changeover circuit of tape recorder | |
JPS5296520A (en) | Signal multiple recording system | |
GB1430210A (en) | Sound reproducing apparatus | |
GB1473532A (en) | Control of fm beat distortion | |
JPS5424528A (en) | Signal recording system | |
JPS564991A (en) | Magnetic recording and reproducing system | |
JPS51141608A (en) | Information and reproduction system |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PS | Patent sealed | ||
PCNP | Patent ceased through non-payment of renewal fee |