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an electronic calculator may operate internally with a greater number of decimal places than can be shown on
its display). The DSP in the VIRTUALIZER operates with a 24 bit resolution. This is accurate enough to
reduce quantizing noise to levels which are usually below the audible threshold. However, when using extreme
equalizer settings, some quantizing side effects may be detected.
Digital sampling has one further, very disturbing effect: It is very sensitive to signal overload.
Take the following simple examing using a sine wave. If an analog signal starts to overload, it results in the
amplitude of the signal reaching a maximum level, and the peaks of the wave starting to get compressed, or
flattened. The greater the porportion of the wave being flattened, the more harmonics, audible as distortion, will
be heard. This is a gardual process, the level of distortion as a percentage of the total signal rising with the
increase of the input signal level.
Digital distortion is quite different, as illustrated by this oversimplified example: If we take the situation where
a 4 bit word has the positive maximum value of 0111, and add to it the smallest possible value of 0001 (in other
words, the smallest increase in amplitude possible), the addition of the two results is 1000 - the value of the
negative maximum. The value is turned on its head, going instantly from positive max to negative max,
resulting in the very noticeable onset of extreme signal distortion.
6. OPERATION
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