Emotiva Big Ego User Manual page 11

About Pre-Ringing and Post-Ringing
Theoretical
F1
Symmetrical Filter
F2
Asymmetrical Low Filter
F3
Asymmetrical High Filter
In order to facilitate converting digital
audio into analog as accurately as
possible, the Big Ego uses what's
known as an oversampling filter or
interpolation filter. While this filter
causes no audible alteration of steady
state signals, when a transient signal
like a drum beat is converted, a tiny
bit of ringing is added to the signal.
While this ringing is not audible as
a separate sound, its presence can
subtly alter the sound character of
the output.
The first picture on the left shows
what a theoretically perfect output of
a certain pulse would look like.
The remaining three pictures show
graphically what that same pulse will
look like after passing through each
of the three filter options on the Big
Ego.
Tests have shown that ringing after
the main signal is less audible than
ringing before it, and many people
perceive the Asymmetrical filter
choices as sounding better, but it's
really a matter of personal preference.