12.25

EUROPA SHAPESHIFTING SYNTHESIZER738
The Amplifier section
The Amplifier section contains a standard ADSR envelope, which controls the amplitude of the signals from all three
Sound Engines equally.
q To create an “amp envelope” for a separate Sound Engine, have a look at “Creating an individual “pre amp en-
velope” for a Sound Engine”.
The picture below shows the various stages of the ADSR envelope:
The ADSR envelope stages.
A(ttack)
When you play a note on your keyboard, the envelope is triggered. This means it starts rising from zero to the value
set with the Gain knob (see below). How long this should take, depends on the Attack setting. If the Attack is set to
“0”, the Gain level is reached instantly. If the Attack value is raised, it will take longer time before the Gain level is
reached.
D(ecay)
After the Gain level has been reached, the level starts to drop. How long this should take is governed by the Decay
parameter.
If you want to emulate the volume envelope of a note played on a piano for example, the Attack should be set to “0”,
the Decay parameter should be set to a medium value and the Sustain level should be set to “0”, so that the volume
gradually decreases down to silence, even if you keep holding the key down. Should you want the decay to drop to
some other value than zero, you raise the Sustain parameter.
S(ustain)
The Sustain parameter determines the level the envelope should rest at, after the Decay stage. If you set Sustain to
full level, the Decay setting is of no importance since the volume of the sound is never lowered.
If you want to emulate the volume envelope of an organ, you theoretically only really need to use the Sustain param-
eter set to full level, as a basic organ volume envelope instantly goes to the maximum level (Attack “0”) and stays
there (Decay “0”), until the key is released and the sound instantly stops (Release “0”).
Attack
(time)
Decay
(time)
Sustain
(level)
Release
(time)
Time
Level
Key Down Key Up
Gain
(level)