Analog Vs Digital

Analog / Digital sound

The act of listening or hearing sound is analog in nature. Analog means it would require physical motion of some sort. For example when we hear the sound of an airplane, the particles in the air vibrate and create disturbance which is picked up by our ears. There is a physical motion of the air particles involved here.

To store analog sounds directly you need some mechanism to record air particle vibrations in some media and replay it later by reproducing the same motions of air particles from the media.

The cassette tape recorder stores the voice in analog format. When we record a voice the vibrations of the air particles are converted into vibrations of magnetic field which are stored on the tape. When we re-play the tape, the magnetic vibrations on the tape are converted back into air particle vibration by the loudspeaker and we can hear the sound again.

On the contrary digital audio is what is stored and processed in the digital format.
You still need to convert it into analog form to hear it using a loudspeaker or headphone as our ear can hear only analog sounds.

Since digital audio involve bits and bytes or rather 1s and 0s, you need some kind of machine which understands 1s and 0s. CD players, computers, DVD players all are digital devices capable of processing digital data and we use them whenever we are dealing with digital audio.

People have been debating the respective merits of analog and digital audio ever since the appearance of digital sound recordings. Generally digital audio as more versatile than analog sound. We can process the digital audio in whatever way we like using the computer or some dedicated hardware. You can cut/paste modify sound the way you like, you can store it on your hard disk or CD easily, download over the internet or send via e-mail.

Analog/Digital recording

An analog recording is one where the original sound signal is modulated onto another physical signal carried on some media such as the groove of a gramophone record or the magnetic field of a magnetic tape. A physical quantity in the medium (e.g., the intensity of the magnetic field) is directly related to the physical properties of the sound (e.g, the amplitude, phase and possibly direction of the sound wave.) The reproduction of the sound will in part reflect the nature of the media and any imperfections on its surface.

A digital recording, on the other hand is produced by first encoding the physical properties of the analog sound into digital information which can then be decoded for reproduction. While it is subject to noise and imperfections in capturing the original sound, as long as the individual bits and bytes can be recovered, the original sound can be reproduced by decoding these bits.