Time (sample and hold) and amplitude (bit reduction) axis quantization.
In addition dither can be applied to both axes. The time axis dither is called "jitter" although this isn't technically accurate.
"Jitter" modulates the frequency of the clock signal for an analog sample & hold by noise. This modulates the position of each individual sample and maintains its fractional position when output. This is unlike a typical jitter where the input and output modulation would be distinct. The effect is to reduce the quantization error over time; true time-axis dither.
- Sample & Hold
- The rate at which to sample & hold the input; 400 Hz to 40 kHz.
- How much to modulate the fractional sample position; up to one sample period.
- Bit Reduction
- The number of bits which represent the amplitude axis from -inf to 0 dB; 2 to 16; including the sign.
- How much white-noise to mix before amplitude quantization.
- Whether the integer amplitude representation is two's complement. The result is either to square a low-level signal (2sc) or to zero it.
Quantization n. A procedure in which a value is limited from a continuous range of values (real numbers) to a set of discrete values (integers).
In the case of the quantizer plug-in we are actually taking one set of discrete values and reducing them to another set of discrete values.