Specifications

Chapter 4: D-Fi 33
Anti-Alias Filter
The Anti-Alias filter works in conjunction with
the Sample Rate control. As you reduce the sam-
ple rate, aliasing artifacts are produced in the au-
dio. These produce a characteristically dirty
sound. Lo-Fi’s anti-alias filter has a default set-
ting of 100%, automatically removing all alias-
ing artifacts as the sample rate is lowered.
This parameter is adjustable from 0% to 100%,
allowing you to add precisely the amount of
aliasing you want back into the mix. This slider
only has an effect if you have reduced the sam-
ple rate with the Sample Rate control.
Sample Size
The Sample Size slider controls the bit resolu-
tion of the audio. Like sample rate, bit resolu-
tion affects audio quality and clarity. The lower
the bit resolution, the grungier the quality. The
range of this control is from 24 bits to 2 bits.
Quantization
Lo-Fi applies quantization to impose the se-
lected bit size on the target audio signal. The
type of quantization performed can also affect
the character of an audio signal. Lo-Fi provides
you with a choice of linear or adaptive quantiza-
tion.
Linear Linear quantization abruptly cuts off
sample data bits in an effort to fit the audio into
the selected bit resolution. This imparts a char-
acteristically raunchy sound to the audio that
becomes more pronounced as the sample size is
reduced. At extreme low bit-resolution settings,
linear quantization will actually cause abrupt
cut-offs in the signal itself, similar to gating.
Thus, linear resolution can be used creatively to
add random percussive, rhythmic effects to the
audio signal when it falls to lower levels, and a
grungy quality as the audio reaches mid-levels.
Adaptive Adaptive quantization reduces bit
depth by adapting to changes in level by track-
ing and shifting the amplitude range of the sig-
nal. This shifting causes the signal to fit into the
lower bit range. The result is a higher apparent
bit resolution with a raunchiness that differs
from the harsher quantization scheme used in
linear resolution.
Noise Generator
The Noise slider mixes a percentage of pseudo-
white noise into the audio signal. Noise is useful
for adding grit into a signal, especially when you
are processing percussive sounds. This noise is
shaped by the envelope of the input signal. The
range of this control is from 0 to 100%. When
noise is set to 100%, the original signal and the
noise are equal in level.
Distortion/Saturation
The Distortion and Saturation sliders provide
signal clipping control. The Distortion slider de-
termines the amount of gain applied and allows
clipping to occur in a smooth, rounded manner.
The Saturation slider determines the amount of
saturation added to the signal. This simulates
the effect of tube saturation with a roll-off of
high frequencies.
Fans of Spinal Tap will be pleased to know that
the Distortion and Saturation controls can be set
to eleven for maximum effect.
Output Meter
The Output Meter indicates the output level of
the processed signal. Note that this meter indi-
cates the output level of the signal—not the in-
put level. If this meter clips, the signal may have
clipped on input before it reached Lo-Fi. Moni-
tor your send or insert signal levels closely to
prevent this from happening.