Quantization

• Where sampling is the process of taking a sample at regular time intervals...

• Quantization is the process of assigning a finite number of possible values to the amplitude of the signal at that sample.

• If amplitude values are represented using $n$ bits, there will be $2^n$ possible values that can be represented.

• If $n=16$ (CD quality),
  • each sample can have $2^{16} = 65,536$ possible values;
  • the highest possible amplitude is $2^{15} = 32,768$, since audio signals are both positive and negative.

• Since the original signal is continuous and can have infinite possible values, quantization error will be introduced in the approximation.

• There are two related characteristics of a sound system that will be effected by how accurately we represent a sample value: