Operation Manual

SUBTRACTOR SYNTHESIZER
195
Filter Envelope Amount
This parameter determines to what degree the filter will be affected by the Filter Enve-
lope. Raising this knob’s value creates more drastic results. The Envelope Amount pa-
rameter and the set Filter Frequency are related. If the Filter Freq slider is set to
around the middle, this means that the moment you press a key the filter is already
halfway open. The set Filter Envelope will then open the filter further from this point.
The Filter Envelope Amount setting affects how much further the filter will open.
Filter Envelope Invert
If this button is activated, the envelope will be inverted. For example, normally the De-
cay parameter lowers the filter frequency, but after activating Invert it will instead raise
it, by the same amount.
Mod Envelope
The Mod Envelope allows you to select one of a number of parameters, or Destina-
tions, to control with the envelope. By setting up a modulation envelope you control
the how the selected Destination parameter should change over time with the four
Mod Envelope parameters, Attack, Decay, Sustain and Release.
The available Mod Envelope Destinations are as follows:
LFO Section
LFO stands for Low Frequency Oscillator. LFO’s are oscillators, just like Osc 1 & 2, in
that they also generate a waveform and a frequency. However, there are two signifi-
cant differences:
• LFOs only generate waveforms with low frequencies.
• The output of the two LFO’s are never actually heard. Instead they are used for
modulating various parameters.
The most typical application of an LFO is to modulate the pitch of a (sound generat-
ing) oscillator, to produce vibrato. Subtractor is equipped with two LFO’s. The param-
eters and the possible modulation destinations vary somewhat between LFO 1 and
LFO 2.
LFO 1 Parameters
Waveform
LFO 1 allows you to select different waveforms for modulating parameters. These are
(from top to bottom):
|
Destination
|
Description
Osc 1 Selecting this makes the Mod Envelope control the pitch (frequency)
of Osc 1.
Osc 2 Same as above, but for Osc 2.
Osc Mix Selecting this makes the Mod Envelope control the oscillator Mix pa-
rameter. Both oscillators must be activated for this to have any effect.
FM Selecting this makes the Mod Envelope control the FM Amount pa-
rameter. Both oscillators must be activated for this to have any effect.
Phase Selecting this makes the Mod Envelope control the Phase Offset pa-
rameter for both Osc 1 and 2. Note that Phase Offset Modulation
(Subtraction or Multiplication) must be activated for this to have any
effect (see page 189).
Freq 2 Selecting this makes the Mod Envelope control the Frequency param-
eter for Filter 2.
|
Waveform
|
Description
Triangle This is a smooth waveform, suitable for normal vibrato.
Inverted Saw-
tooth
This produces a “ramp up” cycle. If applied to an oscillator’s fre-
quency, the pitch would sweep up to a set point (governed by the
Amount setting), after which the cycle immediately starts over.
Sawtooth This produces a “ramp down” cycle, the same as above but in-
verted.
Square This produces cycles that abruptly changes between two values,
usable for trills etc.
Random Produces random stepped modulation to the destination. On some
vintage synths, this is called “sample & hold”.
Soft Random The same as above, but with smooth modulation.