Kurzweil K2661, Musician’S Reference Manual

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10-10
KDFX Reference
KDFX Algorithm Specifications
3 Gated MiniVerb
A reverb and compressor in series.
PAUs: 2
This algorithm is a small reverb followed by a gate. The main control for the reverb is the Room Type
parameter. The main control for the reverb is the Room Type parameter. Room Type changes the structure
of the algorithm to simulate many carefully crafted room types and sizes. Spaces characterized as booths,
small rooms, chambers, halls and large spaces can be selected.
Each Room Type incorporates different diffusion, room size and reverb density settings. The Room Types
were designed to sound best when Diff Scale, Size Scale and Density are set to the default values of 1.00x.
If you want a reverb to sound perfect immediately, set the Diff Scale, Size Scale and Density parameters to
1.00x, pick a Room Type and you’ll be on the way to a great sounding reverb. But if you want experiment
with new reverb
fl avors, changing the scaling parameters away from 1.00x can cause a subtle (or drastic!)
coloring of the carefully crafted Room Types.
Diffusion characterizes how the reverb spreads the early re fl ection out in time. At very low settings of Diff
Scale, the early re fl ections start to sound quite discrete, and at higher settings the early re fl ections are
seamless. Density controls how tightly the early re fl ections are packed in time. Low Density settings have
the early re fl ections grouped close together, and higher values spread the re fl ections for a smoother reverb.
The gate turns the output of the reverb on and off based on the amplitude of the input signal.
A gate behaves like an on off switch for a signal. One or both input channels is used to control whether the
switch is on (gate is open) or off (gate is closed). The on/off control is called “side chain” processing. You
select which of the two input channels or both is used for side chain processing. When you select both
channels, the sum of the left and right input amplitudes is used. The gate is opened when the side chain
amplitude rises above a level that you specify with the Threshold parameter.
The gate will stay open for as long as the side chain signal is above the threshold. When the signal drops
below the threshold, the gate will remain open for the time set with the Gate Time parameter. At the end of
the Gate Time, the gate closes. When the signal rises above threshold, it opens again. What is happening is
that the gate timer is being constantly retriggered while the signal is above threshold.
Figure 10-3 Gate Behavior
0
1
attack
time
gate
time release
time
signal rises
above threshold signal falls
below threshold