Sound-in-Syncs
Sound-in-Syncs is a method of multiplexing sound and video signals into a channel designed to carry video, in which data representing the sound is inserted into the line synchronising pulse of an analogue TV waveform.
History
The technique was first developed by the BBC in the late 1960s.[1]
In the original Sound-in-Syncs system, a single audio channel of about 14 kHz bandwidth was represented by 10-bit linear PCM with analogue companding.
A ruggedised version of the system was developed, which provided about 7 KHz audio bandwidth, for use over noisy or difficult microwave paths, such as those often encountered for outside broadcasts.
Later systems, developed in the 1980s, used 14-bit linear PCM samples, digitally companded into 10-bit samples by means of the NICAM lossy compression algorithm. These were capable of carrying two audio channels and were known as stereo sound-in-syncs.
Awards
Sound-in-Syncs has won several awards, including the Royal Television Society's Geoffrey Parr Award in 1972.[2]
The system won a Queen's Award for Enterprise in 1974.[3]
In 1999, the engineers who developed the system won a Technology & Engineering Emmy Award for the system, nearly 30 years after they designed it.[4]
Notes and references
Further Reading
- Pawley, E (1972). BBC Engineering 1922-1972, pp. 506-7, 522. BBC. ISBN 0 563 12127 0.
- Shorter, D.E.L. (1969), The Distribution of Television Sound by Pulse-code Modulation Signals incorporated in the Video Waveform, EBU Review, No. 113A, February 1969
- Waveform Specification of the BBC Sound-in-Syncs Equipment, EBU Review, 121A, June 1970.
- Dalton, C.J. (1971), A P.C.M. Sound-in-Syncs System for Outside Broadcasts, BBC Engineering, No. 86, April 1971, pp 18-28.
- Shorter, D.E.L., Chew, J.R., Howarth, D. and Sanders, J.R. (1968), Pulse code modulation for high-quality sound signal distribution, BBC Engineering Monograph, No. 75, December 1968
- Sanders, J.R. (1967), Pulse sound: a system of television sound broadcasting using pulses in the video waveform, BBC Engineering Monograph, No. 67, May 1967
- Chorley, J.M. and Shorter, D.E.L. (1970), P.C.M. Sound-in-Syncs: Operational Systems for Video Distribution and Contribution Networks, IEE Conference Publication, No. 69, 1970 International Broadcasting Convention
- Dalton, C.J. (1968), The Distribution of Television Sound Signals by PCM Signals incorporated in the Vision Waveform, IEE International Broadcasting Convention, September 1968, Vol. 46, Part 1