Xils lab PolyKB II, Руководство пользователя

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7.1.3 Filter
The PolyKB’s filter is an accurate dynamic 4 poles self-oscillating low pass filter.
Frequency : This knob sets the cut-off frequency
of the filter.
Response : This knob sets the resonance (or
quality factor) of the filter. When set to the
maximum the filter self oscillates. That means that
it outputs a kind of sine wave even without any
audio signal feeding its input. (Ie even if both
Oscillators are muted)
Keyb Ctrl : set the amount of the keyboard follow
Cut Off modulation.
Adsr2 Ctrl : Set the amount of the second
envelope (ADSR2) applied to the Cut Off
modulation.
Drive: Set the level of the overdrive emulation
circuit. Turning totally left disables it while
turning totally clockwise gives a strong driving
effect. Depending where this stage is placed, pre
or post filtering you can get a subtle low-end
enhancement or a sort of saturation effect.
[DRV Pre/Post] : Clicking on the label [DRV
PRE] or [DRV POST] selects where the driving
stage will stand, before or after the filter.
7.1.4 Envelopes
The PolyKB features two envelope generators (EG). The first one is dedicated to the control
of the output level stage (VCA) while the second is hardwired to control the filter’s Cut Off value.
Thanks to the modulation section, they can also be used for a wide range of other purposes.
An envelope generator is a classic electronic module that outputs a command signal, built on four
parts : ADSR (
A ttack- D ecay- S ustain- R elease )
When the envelope is trigged (generally by hitting a note on the keyboard, or from the output of a
sequencer or an arpeggiator) it begins with the “Attack” part : From zero to the maximum level, the
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