Kurzweil KDFX, Manual

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What is KDFX
The Structure of KDFX
1-5
The Structure of KDFX
The Studio
All of KDFXÕs functions are contained in a Studio . Only one Studio is active at a time.
Up to four stereo or eight mono inputs feed a Studio. The sources for these inputs are the four
output pairs available on the Output pages in the K2500Õs Program and Setup Editors: A, B, C,
and D, which are now called ÒKDFX-AÓ through ÒKDFX-DÓ. Instead of going directly to the
K2500Õs physical outputs, these program outputs now feed KDFX, and only after going
through KDFX do they appear at the physical outputs.
The inputs to the Studio can come from one multi-layered program, or from several programs,
or from the K2500Õs own Sample input when the instrument is in Live Mode.
The input signals pass through an input routing systemÑthe Input Editor . Here, the signals go
through individual two-band equalizers, or EQ s. Then each input, mono or stereo, is routed to
any two of the four FX Bus es.
Each of the FX Bus es contains its own signal-processing program, called an FX Preset . Each FX
Preset has a set of parameters: for example the RT
60
value on a reverb, or the Feedback level on
a delay line. These parameters can be Þxed as part of the FX Preset, or they can be externally
controlled, from one of two different places. The four FX Buses are also called Ò
Insert FX
Buses Ó, because in a conventional studio, thatÕs where they would be found: in the insert loop
of a mixer, between the channel input and the mix bus.
There is a Þfth FX Preset, which is located on the Auxiliary FX Bus . The Aux FX Bus follows the
four main FX Presets in the signal path, and is normally conÞgured as a ÒglobalÓ processor.
Each FX Preset is based on an FX Algorithm . An Algorithm is a processing function, like a
reverb, ßanger, or compressor; or a combination of processing functions in a particular order,
like a ßanger followed by a delay followed by a reverb. The Algorithms themselves are Þxed in
ROM, like Kurzweil ROM samples, but the values of their operating parameters can be
changed.
☛
The selection of an Alg its user-controlled parameters = an FX Preset.
Each Algorithm requires a certain amount of processing power, which is expressed in
ÒProcessing Allocation UnitsÓ (or
PAU s). Simple Algorithms will require 1 PAU, while more
complex Algorithms will require up to 4 PAUs. The amount of processing power available in
each FX Preset is set by its
Allocation parameter. When you are selecting an FX Preset for an
insert bus, the number of PAUs its Algorithm requires appears on the display, so you can keep
track of how many PAUs are in use.
PAUs are shared among the four Insert FX buses. There is a limit to the total number of PAUs
that the insert buses can use, and that limit is 4. PAUs can be manually pre-assigned to speciÞc
FX Buses, or using ÒAutoÓ mode they can be assigned automatically as FX Presets are assigned
to the buses. The Auxiliary FX Bus has a separate set of PAUsÑ3 of themÑwhich are
not shared
with the insert buses.
Finally, the outputs of the FX Presets are sent to an output routing systemÑthe Output
Editor Ñwhere they are then sent to the physical outputs of the K2500.
☛
EQs + Input Editor se FX P Output Editor settings = a Studio
On the following page is a schematic overview of a StudioÕs structure.