combinations of zeroes and ones, so 65,535 different voltages can be
digitally represented. (see figure A above).
Figure B. The more bits there are available, the more accurate
the representation of the signal and the greater the dynamic
range.
Your Echo card’s analog inputs use 24-bit ADCs, which means that the
incoming signal can be represented by any of over 16 million possible
values. The output DACs are also 24-bit; again, over 16 million values are
possible. Your Echo card processes signals internally with 24-bit resolution
to insure that there is no degradation to the audio signal as it is processed
through the system.
The number of bits available also determines the potential dynamic range of
the device. Moving a binary number one space to the left multiplies the
value by two, so each additional bit doubles the number of possible values
that may be represented. Each doubling of the number of values provides
6dB of additional dynamic range (see decibel section below). So, a 24-bit
system can theoretically provide 144dB of dynamic range (6dB times 24 bits
= 144dB) versus a 16-bit system with a maximum dynamic range of only 96
dB.
Also important to the quality of a digital recording is the frequency with
which the samples are stored, called the sample rate. In order for a
waveform to be faithfully digitized, it must be sampled at a minimum of
twice the highest frequency to be stored. Failure to sample frequently
enough results in a kind of distortion called aliasing. (If you like technical
issues, do some research on The Nyquist Theorem which explains why this
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