Korg KROSS Parameter Manual page 56

Program mode
Shape
This controls the amount of curvature, and whether the curves are
concave or convex. As you can see in the graphic examples, the
shape will tend to emphasize certain value ranges, and de-
emphasize others.
For example, let's say that you are using a triangle LFO, through
Shape, to modulate filter cutoff. If Shape emphasizes the high
value range, the filter will spend more time at the higher
frequencies. If it emphasizes the low range, the filter will spend
more time at the lower frequencies.
Mode
This selects whether the Shape parameter will produce one or two
curves. The graphic "AMS Mixer Shape examples" may help to
visualize how this works.
Asymmetric will produce a single curve, extending from
–99 to +99.
Symmetric will produce two matching curves extending outwards
from 0 to –99 and +99, respectively.
Bipolar and Unipolar AMS sources
To understand Shape, it helps to understand the difference between
bipolar and unipolar AMS sources.
Bipolar sources can swing all the way from –99 to +99, with 0 in
the middle. Most LFOs are bipolar, for instance; so is Pitch Bend.
Generally, bipolar AMS sources will work better with the
Asymmetric mode, but Symmetric may also produce interesting
results.
Unipolar sources only go from 0 to 99, with 50 in the middle.
MIDI controllers, such as M.Wheel: #01, are all unipolar. In
practice, EGs are usually programmed to be unipolar, even though
the Filter and Pitch EGs do allow both positive and negative
levels.
With unipolar sources, it's almost always better to use the
Symmetric mode. The Asymmetric mode can cause offsets and
other strange results.
48
[–99...+99]
[Symmetric, Asymmetric]
AMS Mixer Shape examples
Bipolar Triangle Wave
Asymmetric
+99
0
–99
Symmetric
+99
0
–99
Bipolar Sawtooth Wave
Asymmetric
+99
0
–99
Unipolar Triangle Wave
Asymmetric
(not recommended)
+99
0
–99
Shape = 0 (original waveform)
Shape = +99
Shape = –99
Quantize
This Mixer Type changes the input from a continuous signal into a
series of discrete steps. Instead of moving smoothly between
values, it will snap immediately from one value to another.
You can use this to change the shape of LFOs or EGs, or to force a
controller to land on a few specific values.
AMS Mixer Quantize examples
Unipolar (e.g., Bend(+))
+99
Original
0
AMS A
–99
+99
Quantize
0
Steps = 8
–99
+99
Quantize
0
Steps = 16
–99
AMS A
This selects the AMS input source to be quantized.
Symmetric
Symmetric
Bipolar (e.g., LFO)
[List of AMS Sources]