About Audio Recording (1) Brief introduction of audio recording
This article is for those interested in the technical side of audio recording. The two classes of audio recording technologies are covered.
First of all, I'd like to introduce the history of sound recording in brief. Audio recording also called as sound recording. To trace back as far as 9th century, the first devices for recording and reproducing sound were mechanical in nature and could not record arbitrary sounds like human voice. In 1857, phonautograph was invented and it was the first device that could record sound mechanically.
Generally speaking, audio recording consists of two different processes. One is the process of recording the sound signal to the medium. Another is to play the recorded sound from the medium. Audio recording and reproduction is an electrical or mechanical inscription and re-creation of sound waves. The two main classes of audio recording technology are analog recording and digital recording.
Analog recording is a technique for recording analog signals to playback later. It stores signals as a continual wave in the media. Examples of analog audio recording are:
Digital recording and reproduction converts the analog sound signal to a digital form by a process of digitization so that it can be stored and transmitted by a wider variety of media. Simple as editing Word documents, we can edit the recorded sounds as we like. A digital audio signal must be reconverted to analog form during playback before it is applied to a loudspeaker or earphones.
The advantages of analog systems are summarized in three factors like absence of aliasing distortion, absence of quantization noise, behaviour in overload conditions. Maybe digital systems are more practical. It is much easier to make editing through rapid random access, seeking and scanning for non-linear editing. It is hardly to say which recording is superior because the sound quality depends on the quality of the system and many other factors.