Korg NAUTILUS Series, Parameter Manual, Page: 245 / 961

PROGRAM > STR-1: Filter 5–1: Basic
235
Parallel. This also uses both Filter A and Filter B. Unlike
Serial, above, the outputs of the two filters are kept separate,
with individual control over both level and pan.
24dB (4-Pole). This merges both filters to create a single 4-
pole, 24dB/octave filter (12dB for Band Pass and Band
Reject). In comparison to Single, this option produces a
sharper roll-off beyond the cutoff frequency, as well as a
slightly more delicate resonance. Many classic analog synths
used this general type of filter.
When 24dB (4-Pole) is selected, only the controls for Filter
A are active; the controls for Filter B will be grayed out.
Also, note that the
Multi Filter is not available in this mode.
5–1b: Filter A
Filter Type [Low Pass, High Pass, Band Pass,
Band Reject, Multi Filter]
The filter will produce very different results depending on
the selected filter type. The selections will change slightly
according to the selected
Filter Routing , to show the correct
cutoff slope in dB per octave.
Low Pass. This cuts out the parts of the sound which are
higher than the cutoff frequency. Low Pass is the most
common type of filter, and is used to make bright timbres
sound darker.
High Pass. This cuts out the parts of the sound which are
lower than the cutoff frequency. You can use this to make
timbres sound thinner or more buzzy.
Band Pass. This cuts out all parts of the sound, both highs
and lows, except for the region around the cutoff frequency.
Since this filter cuts out both high and low frequencies, its
effect can change dramatically depending on the cutoff
setting and the oscillator’s multisample.
With low resonance settings, you can use the Band Pass
filter to create telephone or vintage phonograph sounds.
With higher resonance settings, it can create buzzy or nasal
timbres.
Band Reject. This filter type–also called a notch filter–cuts
only the parts of the sound directly around the cutoff
frequency. Try modulating the cutoff with an LFO to create
phaser-like effects.
Multi Filter. This is a complex filter which is capable of all
of the above filter types, and many more besides. For more
information, see “5–2: Multi Filter,” on page 237.
The Multi Filter is available only for Filter A, and only when
the Filter Routing is set to
Single , Serial or Parallel .
Filter Types and Cutoff Frequency
Bypass [Off, On]
This lets you bypass Filter A completely.
If Bypass is Off , Filter A functions normally.
When Bypass is On , Filter A has no effect on the input
signal.
Trim [00…99]
This adjusts the volume level at the input to Filter A. If you
notice that the sound is distorting, especially with high
Resonance settings, you can turn the level down here, or at
the Output Level.
Note that the filter will not clip internally, so there is no
difference between adjusting the Input Trim and the Output
Level. Either of these controls will allow you to minimize
clipping later in the signal chain, such as may occur in some
effects.
Output Level [00…99]
This controls the output level of Filter A. You can use this to
balance the volumes of Filters A and B when the Routing is
set to Parallel, or to turn down the volume to avoid clipping
later in the signal chain.
AMS [AMS Sources]
This selects a modulation source to control the Output
Level . For a list of AMS sources, see “Alternate Modulation
Source (AMS) List” on page 901.
Intensity [–99…+99]
This controls the depth and direction of the Output Level
modulation.
Low Pass
High Pass
Band Pass
Band Reject
Cutoff Frequency