Example 3; Sample And Hold; Using A Fun - Kurzweil K2000 - MUSICIANS GUIDE Musician's Manual

Programming Examples

Example 3

Example 3

Sample and Hold; Using a FUN

This example will use one of the FUNs to create a sample and hold program. As usual, start
with Program 199, and press EDIT. While youÕre on the ALG page, select a value of
ÒPARAMETRIC EQÓ for the center DSP function block. Then select the KEYMAP page, and
select the keymap 152 Dull Sawtooth.
Now press the more> soft button, then the F1 FRQ soft button. This enables you to set the
frequency for the parametric EQ, which will set the depth of the modulation for the sample and
hold function. The Coarse parameter will already be selected; set its value to D#4 311 Hz.
Cursor down to the KeyTrk parameter, and set its value to 100 cents per key. Cursor over to the
Src1 parameter, and set its value to FUN1 (1, 1, 2, ENTER). Cursor down once to the Depth
parameter, and set its value to a fairly large negative number, like -4000 cents.
Next, press the F3 AMP soft button, to set the amplitude for the Parametric EQ (make sure you
donÕt select F4 FINAL AMP). Set the value of the Adjust parameter to about 17 dB.
Now press either <more> soft button until you see the LFO soft button. Press the LFO button to
select the LFO page. WeÕll program LFO1 as a square wave, then use it as one of the FUNÕs
inputs.
Select the MnRate parameter for LFO1 and set it to a value of 5.00 Hz. Select the MxRate
parameter and set its value to 9.40 Hz. Select the RateCt parameter and set it to a value of Data.
Select the Shape parameter and set its value to Square. ThatÕs it for the LFO page.
Next press the FUN soft button to select the FUNs page. Select the Input A parameter for FUN1,
and set its value to LFO1 (1, 1, 4, ENTER). Select the Input B parameter and set its value to
RandV1 (1, 0, 8, ENTER). Finally, select the Function parameter, and set its value to ÒSample B
On A.Ó Now when you play and hold a note, youÕll hear the sample and hold effect. Use your
MIDI controllerÕs data slider (or a programmable control set to MIDI 06) to control the rate of
the effect.
HereÕs whatÕs happening. Every time the square wave LFO cycles, the value of the random
signal generator (RandV1) modulates the frequency of the parametric EQ. There are lots of
ways to set up sample and hold effects, but the FUN is the basic element. In this case, every
time the value of the FUNÕs ÒAÓ input becomes greater than +.5, the value of the ÒBÓ input is
sampled. That value becomes the FUNÕs output until the next time the value of the ÒAÓ input
becomes greater than +.5 (see Chapter 16 for more). In this example, the FUNÕs output
modulates the frequency of the EQ, and since it happens so rapidly, the effect is almost like a
random tremolo.
Now weÕll apply the FUN to control the pitch of the sound as well. Press either of the <more>
soft buttons until the PITCH soft button is visible, and press it to select the PITCH page. Select
the Src1 parameter and set its value to FUN1. Select the Depth parameter and set its value to
about 400 cents. Now the soundÕs pitch will ßuctuate in sync with the EQ effect.
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