Korg NAUTILUS Series, Parameter Manual, Page: 147 / 961

EXi PROGRAM > Modulation 5–1: Common Step Seq
137
5–1a: Step Sequencer
Mode [Loop, One Shot]
Loop makes the Step Sequence loop continuously between
the Start Step and the End Step .
One Shot makes the Step Sequence play once from the Start
Step to the End Step , and then hold at the End Step . You
can still reset the Step Sequencer from AMS to make it play
again.
Start Step [1…32]
This sets the step on which the sequence will start. The Start
Step is important for the Mode parameter, above. You can
also modulate it via AMS.
AMS [AMS Sources]
This selects an AMS source to modulate the Start Step . For
a list of AMS sources, see “Alternate Modulation Source
(AMS) List” on page 901.
Intensity [-32…+32]
This controls the depth and direction of the Start Step
modulation.
End Step [01…32]
This sets the last step in the sequence. Once the sequence
reaches the
End Step , it will either hold there until the note
goes away (if Mode is set to One Shot ), or loop back to the
Start Step (if Mode is set to Loop ).
Smoothing
These controls filter the Step Sequencer’s output signal,
creating more gentle transitions between values. You can use
this to round off the hard edges of the Step Sequencer’s
output, or to create envelope-like effects.
You have separate control of the amount of smoothing
during the attack (when the signal is increasing) and decay
(when it’s decreasing).
Attack [00…99]
This controls the attack time of the smoother, or how long it
takes to reach a new,
higher value.
Higher Attack settings mean longer times.
Depending on how quickly the Step Sequencer value is
changing, high Attack settings may mean that a new value is
never quite reached.
Decay [00…99]
This controls the decay time of the smoother, or how long it
takes the smoother to reach a new,
lower value.
Higher Decay settings mean longer times.
Using Smoothing to create envelope-like shapes
Since you have separate control over the attack and decay
times, you can use Smoothing to create envelope-like pulses.
To do so, you’ll need to alternate
Step Values so that a
positive value is followed by a value of zero. (You could use
negative values, as well, but that would make the action of
the
Attack and Decay controls more complicated.)
To hear the effect clearly, let’s use an AL-1, and assign the
Step Sequencer to modulate Filter Cutoff:
1. In a single EXi Program, set EXi1 to AL-1.
2. Set the Filter Type to Lowpass, and the Routing to
24dB (4-pole).
3. Set the Filter Cutoff to 00.
4. On the Filter Mod page, set Filter A’s AMS to
Common Step Sequencer, and set the Intensity to 90.
You could also use the per-voice Step Sequencer, but for this
example we’ll use the Common one.
5. In the Common Step Sequencer, set the End Step to 4.
6. Set the Mode to Loop.
7. Set Step 1’s Value to +100.
8. For both Step 2 and Step 4, set the Value to 0.
9. Set Step 3’s Value to +80.
10.Set the Durations of all four Steps to a 32nd-note.
11.Turn the
(Tempo) at about 120 bpm.
If the tempo is really fast, you’d need to use longer Step
Durations.
12.Set the Smoothing Attack to 0.
13.Adjust the Smoothing Decay to 80.
Now, the Step Sequencer will create a series of 16th-note
pulses, like simple envelopes. With the settings above, they
“envelopes” will have an instant attack, and a moderate
decay/release time.
For more space between the pulses, try this:
14.For both Step 2 and Step 4, set the Duration “x”
(Multiply Base Note by…) to 3.
This creates a series of 8th-note pulses, with a longer time
between each pulse.
15.Adjust the Decay between 0 and 99, and listen to the
difference that it makes.
You can also create smoother, LFO-like effects. Try this:
16.Set the Decay to 80, and then vary the Attack time.
With longer Attack times, the pulses become softer in
character.
Using Smoothing to make step transitions more
gentle
Without smoothing, the Step Sequencer’s output has very
sharp transitions between values. Often, this may be just
what you’re looking for. In some cases, however, these
transitions may cause audio artifacts, such as low-frequency
bumps. This will depend on the parameter being modulated,
and the intensity of the modulation.
If this happens, you can use smoothing to make the
transitions more gentle, and reduce or eliminate the artifacts.
To do so:
1. Adjust the smoothing until it’s just high enough that
the artifacts are no longer heard. Start with the Decay,
and then use Attack if necessary.
When using positive Step Sequencer values and positive
modulation, you’ll generally only need to adjust the Decay;
otherwise, you may need to adjust the Attack as well.
The trick is to set the smoothing high enough so that the
artifacts go away, but low enough that the sound of the Step
Sequencer isn’t altered significantly.