Kurzweil Forte - Advanced Use of KVA Oscillators; Examples of Simple DSP Control and Modulation

Program Edit Mode
Editing VAST Programs With KVA Oscillators
7-75
when the Synco parameter is modulated during performance. Use the DSPMOD page
to assign an envelope or continuous controller like the Mod Wheel for this parameter to
hear the eect (see The DSP Modulation (DSPMOD) Page, as well as The DSP Control
(DSPCTL) Page and Common DSP Control Parameters in Algorithm Basics on page
7-34, for details on setting up modulation and other ways to control parameters, and see
The Envelope 2 (ENV2) and Envelope 3 (ENV3) Pages for details on using envelopes as
modulation sources). See Advanced Use Of KVA Oscillators below for some similar examples
of how to set and control modulation for oscillator specic functions and other parameters.
To add a DSP function to the Sync Square oscillator, you’ll need to use cascade mode. For
example, to add a lter, duplicate one of the layers to create layer 3. On layer 3, select the
ALG page and choose one of the cascade mode algorithms, algorithms 101-131. For this
example, lets use alg 105 with the lter “4Pole Mogue LP” selected for the function block.
For the Alt Input parameter, select Layer 2. is routes a pre-Level parameter copy of Layer
2’s output into Layer 3. Go to layer 2’s DSPCTL page and turn its level down to -96dB
(otherwise the un-ltered sound from layer 2 will be audible as well as the ltered sound in
layer 3). Now you can hear the Sync Square from layers 1 and 2 running through the lter in
layer 3. See Advanced Use Of KVA Oscillators below for examples of how to set and control
modulation of lter parameters.
Advanced Use Of KVA Oscillators
Read the KVA sections above before moving on to this section.
If you have tried the program described above in Basic Use of KVA Oscillators, you may have
noticed that there is no variation in the notes played aside from pitch. Layers and programs
created with KVA oscillators can become much more expressive by introducing variation
with DSP modulation. For a KVA oscillator layer, you can use DSP modulation just as you
would for keymap layers (see Common DSP Control Parameters, The DSP Modulation
(DSPMOD) Page, and The DSP Control (DSPCTL) Page). Several KVA oscillators also
have their own modulation parameters that must be accessed to control the oscillator’s
intended function. Aside from these methods, KVA layers can also be altered by using
keymaps with natural amplitude envelopes. See below for details on each method.
Examples of Simple DSP Control and Modulation:
Select the Program 998 Editor Template and press the EDIT soft button. Go to the
KEYMAP page and set Keymap to 999 Silence. Next, go to the AMPENV page and set
the mode to User, set Att1 time to .002 and Rel1 time to 0.02 (this gives you basic control
of attack and release envelopes with sliders C and D). Press the ALG soft button and select
Algorithm 8. Select the leftmost empty function block and use the alpha wheel to scroll to
the PWM oscillator. Play some notes to hear the sound of the PWM oscillator.