FXPANSION DCAM SYNTH SQUAD, Operation Manual

Page: 59 / 110

59
Envelope
An envelope allows you to shape a sound over time, from its
beginning to its end. It is sometimes called a ‘contour’.
The Amp Envelope is directly routed internally to the
Amp
parameter in Strobe and Cypher. This is to avoid needing
to make a dedicated modulation connection between them
purely for engaging the amp so that notes can be heard.
Amber’s paraphonic architecture means that it doesn’t have
a conventional amp envelope, but dedicated Synth and
Ensemble envelopes that dictate the amplitude shape of
each paraphonic note. These envelopes are special cases,
and are explained in section 5:9.
Mod Envelopes, meanwhile, can be used for a variety of
purposes. They are similar to the second envelope typically
found on many monophonic and polyphonic synths, which
were usually routed to the filter cutoff or oscillator pitch. The
TransMod system allows you to route Mod Envelopes to any synth parameter.
ADSR controls
Atk
(
Attack
),
Dcy
(
Decay
) and
Rel
(
Release
) are time periods, while
Sus
(
Sustain
) is a
level, expressed in %.
When the envelope is gated, the following processes occur:
• The envelope level rises from 0 to 1 over the defined
Attack time
• After this has been reached, it decays towards the level defined by the Sustain control,
over a time period defined by the
Decay
parameter (if Sustain is at 100%, there is
effectively no Decay stage).
• This occurs as long as the envelope is gated (while the gate signal is ‘on’). Whenever the
gate is released (when the gate signal returns to an ‘off’ state), no matter which stage has
been reached, the envelope’s level falls to 0 over the time defined by the
Release
parameter.
All of these parameters can be modulated with the TransMod system.
Sync
With the Sync button enabled, the time-based envelope controls ( Attack , Decay , Release ) are set in BPM units. With the
Sync button disabled, these controls operate in seconds.
Loop
Enabling the
Loop
button causes the envelope to repeat after it has completed the
Attack
and
Decay
phase. After the
Decay time is complete, the envelope starts again - this continues while the envelope is gated. If the Sustain control is
higher than 0, the envelope travels towards the sustain level and remains at this level for the duration of the Decay time.
When the gate is released, the level of the looping Attack and Decay stages is scaled down to 0 over the
Release time.
The level of the envelope returns to 0 when it is gated, and at the end of each ‘loop’ (after each decay stage).
The Loop function is great for simulating echo/delay effects on gate release or for providing an additional LFO capable of
alternative shapes.
Lin (Linear)
By default, the Attack , Decay and Release phases of envelopes react exponentially. When the Linear button is enabled,
their behaviour changes to a linear response. The difference between the two is illustrated by the following diagram:
Exponential envelope (
Linear
button off)
0.5 1.0 1.5 2.0
Time S
0.2
0.4
0.6
0.8
1.0
Voltage V
0.5 1.0 1.5 2.0
Time S
0.2
0.4
0.6
0.8
1.0
Voltage V
Linear envelope (
Linear
button on)