The first demonstration of analog recording for audio was done by Thomas Edison. Analog sound recording is a technique to store audio signals as a continual wave in or on media. Usually the wave is stored physically on a phonograph record or on a magnetic tape. This is ratgher different from digital recording which converts audio signals into binary or hexadecimal numbers.
The main difference between analog and digtal sound comes from the way of recording. As the actual sound waves consist continuous variations of air pressure these signals can be recorded using digital of analog techniques.
Analog recording versus digital recording compares the two ways in which sound is recorded and stored. Actual sound waves consist of continuous variations in air pressure. Representations of these signals can be recorded using either digital or analog techniques.
With an analog sound recording generally the air pressure variations are converted into an electrical analog signal and are recorded to a medium by a recording machine such as tape recorder. Usually analog signal is recorded on a magnetic tape or gramophone disc. The main thing what makes recording analog is physical quality of the medium and its direct relation to the properties of the original sound.
With digital recording the sound is converted into sequence of numbers and can be stored on digital devices such as hard drive. With recording the digital sound it usually starts with analog way by recording it with microphone and digitalized through analog-to-digital converter. The main difference between analog and digital signal is that analog is continuous in time and digital is not. Not continuous means that with digital sound it has parts that follow one after another with definite division points between them. Also analog signals are continious in amplitude and digital signals are quantized. Continious analog signals means that they have no artificially set limit on possible instantenous levels, but digitally-processed quanitzed signals have a precise, limited number of possible instantaneous values called as quantization levels and there is impossible to have value between two adjacent quantization levels, which is making digital signals most advantage than analog signal.
It’s has been a discussion whether to use analog or digital audio and which of them is better. The main reason is highly related to the sound quality. High quality sound production is possible with both analog and digital systems. Expensive and excellent analog systems may be better than digital systems and vice versa. The most limiting aspect of analog sound is the sensitive media to minor physical damage, however analog systems usually perform better and produce recognizable sound even if minor damaged. Digital systems usually fail completely and are unable to playback anything from the medium. The main advantage is that digital systems are very flexible and low-cost in duplication and signal is direct usable in portable storage and playback devices. By comparison analog require high-quality playback equipment to play the signal from media. Analog equipment imperfections can cause different distortions like tape hiss, wow and flutter or when the medium wears out there will be surface noise as with old vinyl records.
In the development stage of the Compact Disc, engineers understood that the spiral bits perfection is critical for playback. A small scratch could corrupt many bits and can couse loss of synchronization of the clock and data. This was fixed with error-correction coding what is basically a mathematically encoded backup copy of the CD data. Error correction in digital formats means to tolerate more media deterioration than analog formats. Occasionally there can be difficulties with rewriteable CDs. Usually it is because of poor-quality CD recorders or low-quality discs. Most of the CD discs are sensitive to UV light. Digital copies are usually exact replicas and can be duplicated indefinitely without degradation. Unlike digital systems, there are only few selectable recording speeds with analog systems. There is more practical advatages of digital systems over analog systems . Digital computer-based systems make sound editing much easier through quick acess, seeking and scanning. There is possibility to add non audio information into digital stream, such as artist name, track title etc.
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