Kurzweil K2600 Musician's Manual page 465

parameter immediately below Tempo, Period, multiplies or divides the tempo. The Period is
expressed in beats (bts) and ranges from 1/24 (the actual time is 24 times faster than the Tempo)
to 32 (the time is 32 times slower than the Tempo) in a sliding scale based on 24ths of a beat. So
for example, if an LFO has a Tempo setting of 120 BPM and a Period of 12/24 bts, the LFO will
oscillate 240 times per minute, or 4 Hz.
Variable Tempos Using System
You can also have these parameters respond to tempo in real time, by setting the Tempo
parameter to System, which is set by scrolling below 1 BPM (or pressing 0 and Enter on the
alphanumeric buttonpad). Now instead of Tempo being a Þxed value, it will vary according to
the system clockÑwhich, depending on the setting of the Clock parameter on the Song modeÕs
MISC page as described above, will either be the internal sequencerÕs clock, or tempo coming
from an external source of MIDI Clock. The System Tempo will be multiplied or divided by the
Rate or Beats setting, to determine the parameterÕs actual speed, just as if it were a Þxed value.
If the Clock setting is Int, then the current tempo of the internal sequencer (as shown on the
Song ModeÕs MAIN page) will be in effect regardless of whether the sequencer is running.
If the Clock setting is Ext, the external sequencer (assuming it is sending MIDI Clock) controls
the Tempo parameter. If no MIDI Clock is being received by the K2600, the tempo will not go to
0; instead, it will retain the last valid value it sawÑeither the tempo of the internal sequencer at
the time when you switched the Clock to Ext, or the last tempo sent by an external sequencer
before it stopped.
Tempo as an FXMod Source
KDFX algorithms that donÕt have a Tempo parameter can also respond to tempo information,
using FXMods.
In the Source list, there is a value called Tempo, located at number 55. This source reads the
current tempo (Þxed or variable, internal or external) and turns it into a numerical value
between 0 and 1, which is then applied to the parameter under the control of the FXMod. The
ÒvirtualÓ range of this parameter is 3.75 to 240 BPMÑthat is, a tempo of 3.75 BPM (or less) will
set the parameter value to 0, while a tempo of 240 BPM (or greater) will set it to 1. Of course,
most parameters donÕt actually vary between 0 and 1, so you have to scale the real values
appropriately.
This can get pretty confusing, but there is a relatively simple method to follow when using this
feature: set the Adjust value of an FXMod to the value of the parameter that you want when the
tempo is 3.75 BPM, and set the Depth value so that the sum Adjust+Depth equals the value that
you want when the tempo is 240 BPM.
For example, letÕs look at an algorithm that has an LFO Rate parameter in Hz. LetÕs say we want
to the LFO speed to be twice as fast as the tempo. Here are the values for the FXMod:
Parameter LFO Rate
Adjust The slowest vibrato we want is (3.75 BPM/60) x 2, or 0.125 Hz. 0.13 Hz is the nearest
value available.
Source Tempo
Depth The fastest vibrato we want is (240BPM/60) x 2, or 8.00 Hz, so this parameter is
8.00Ð0.13, or 7.87 Hz; the nearest value available is 7.80 Hz.
The Tempo value exists in Control Source lists throughout the K2600Õs operating system, not just
in FXMod pages, so you can use it for controlling just about any function, including pitches of
sample loops, envelope lengths, Þlters, volume, and more.
Advanced KDFX
Real-time Control of KDFX
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