How is sound digitized?

Answer 1

Sound is a time dependent pressure variation in air. A microphone translates this to a varying voltage on a wire. Analog recorders record this signal by storing the varying voltage on magnetic tape as a varying magnetization in a strip of tape coated with a magnetic material. Digital recorders first digitize the signal by rapidly taking samples of the voltage, perhaps 30000 samples every second. Each sample is then digitized by a device called an A-D converter. The digital numbers from this converter are stored digitally in various ways, eg, in pits cut in a disc by a laser. The A-D converter is the heart of the digitization process. Typically it is a chip sold by one of several companies. How this works is too complicated for the space we have here. Look at this reference for more info. http://en.wikipedia.org/wiki/Analog-to-digital_converter

Answer 2

Digital sound, in its most basic form, is a string of numbers (sample values) indicating the relative intensity of the sound at regular intervals. For CD quallity, there are 44,100 intervals per second (Samples/second), and each sample is represented by a 16 bit signed integer value in the range -32768 to 32767. Proffesional recording studios typically use 48,000 or 96,000 samples/second with 24 bit samples. After all of the effects are added and the various instruments mixed together, it is "resampled" to the CD specification. To digitize sound, a ramp wave is started on regular intervals several times faster (as much as 128 times faster) than the sample rate. This is called "oversampling". When the voltage of the ramp wave matches the voltage of the input signal, the time it took is measured. At the end of the sample interval the times are used to determine the intensity of the signal. The inputs on your computer's sound card (or integrated sound chip) do this continuously while your computer is running, even if nothing is plugged into them!

Answer 3

Sound waves cannot be digitised it can be transformed