Quantization Resolution

Digital audio is just another recording medium like cassette tape and vinyl records. Cassette and vinyl records had a dymanic range (loudest volume / softest volume) of 60dB to 80 dB.

When the audio CD format was being developed, the Sony and Philips people decided to encode each audio sample as a 16 bit number which have a range of -32768 to 32767.

With 16 bit audio, the loudest signal can have an amplitude of 32767 and the softest signal an amplitude of 1 resulting in a dynamic range of a bit over 90 decibels which would seem sufficient.

For certain applications, people are using 24 bit integers and 32 bit floating point values to store audio data.

Pulse Code Modulation

When we sample a signal, then quantize the samples and code them as binary values, we create a Pulse Code Modulation (PCM) signal. This PCM signal is a long string of numbers.

back.png next.png