Published in Technology
What surrounds what in “Surround Sound”, and why is it so called?
Why a typical surround sound system is called a “5.1 system” ?
A little bit of history of “sound recording and reproduction” will help to build a context to answer these questions meaningfully. Here it is. The method of recording sound and reproduction evolved between 1920 to 1945. At around 1950, two things were achieved.
- Sound could be converted to electrical signals to a fair degree of accuracy using microphones and recorded on magnetic tapes and
- These tapes later could play back the recorded sound with some degree of fidelity - meaning closeness to the original sound.
During those days listening to quality musical performances was only possible live – you had to be there at the performance. For a long time AM Radio stations reached out to millions by replaying recorded sound of such performances. Radios of those days, had one small speaker. Since all sound (instruments and the voice of the vocalist) come from this speaker only, this mode of listening was called “monaural” – meaning “one sound”.