# Digital Audio: Part 4 - ADC’s & The Mathematics Of Quantization & Dither

Digital audio relies completely on the accuracy of quantization and it is important to see how it works.

Fig.1 - Sampling and quantizing can be performed in either order. At a) the sampling goes first. At b) the quantizing goes first.

Fig.2 - A continuously variable system can be compared to a ramp, where any height is possible. A quantized system is more like a ladder, where only certain heights are available.

Fig.3 - The mid-tread quantizer makes the numbers proportional to the input voltage because zero digital corresponds to zero Volts.

Fig.4 - The sawtooth-like quantizing error of an ideal convertor cannot exceed +/- 1/2 Q.

Fig.5 - With small signals, the quantizing error is a function of the audio waveform and must be classed as a distortion.

Fig.6 - Practical audio convertors use dither to linearize the system by making the quantizing error random.

# Information: Part 5 - Moving Images

Signal transducers such as cameras, displays, microphones and loudspeakers handle information, ideally converting it from one form to another, but practically losing some. Information theory can be used to analyze such devices.

# Broadcast Audio System Design: Part 1 – Overview

We begin our series on things to consider when designing broadcast audio systems with the pivotal role audio plays in production and the key challenges audio presents.

# Transforms: Part 7 - Standards Conversion

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# Electricity: Part 5 - Wind Turbines

Wind turbines are increasing in number because they produce electricity with reasonable environmental impact. But how green are they really?

# Information: Part 4 - Data Rates

In an increasingly digital world, it may be useful to look at the amount of data needed to represent various media. Note that the amount of data is being considered; the amount of information will always be somewhat less than…