User Guide

150
Module: Shaper 3
Filter envelope
You will find a basic description of an ADSR
envelope’s four parameters as well as a picture of its
curve on page 99.
A filter envelope shapes the sound far more
perceptibly than, for example, an amplifier
envelope. This makes it ideal for emulating the
response of acoustic instruments. Take a note played
on a stringed instrument: It not only grows softer
but also loses its brightness as it fades. You can copy
this effect using the sustain and release parameters
of an ADSR envelope and decreasing the selected
filter’s cutoff frequency over the time that the note
is held. Now take a brass instrument: Some latency in
its attack is typical. It takes a moment for the full
frequency spectrum of the tone to become audible.
The attack parameter of the ADSR envelope is perfect
for imitating this property.
The filter envelope changes the sweep of the cutoff
frequency, thus shaping the signal’s timbre!
Velocity-driven envelope effects
Velocity can be used to shape the depth parameter
that controls the filter envelope’s modulation
intensity. To do this, you must enter a value other
than zero for shaper 3’s velo depth parameter (see
the parameter description on page 152).
Normal or repeat?
As described for shapers 1 and 2, in Normal mode the
envelope runs through once only every time a key is
pressed. After the release time elapses, it takes a
new note to re-trigger the envelope.
The envelope is cycled when you select the repeat
mode. However, the envelope does not run its full
course because the sustain phase is truncated. After
the decay time elapses, the envelope jumps directly
to the release phase, which in repeat mode runs its
course even whilst holding the key down issues a
note-on command. Then the curve re-enters the
attack phase. This cycle continues for as long as the
key is held down. Once the key is released the
envelope ends after the release phase.
On page 103 you will find an illustration of an ADSR
envelope in repeat mode.
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