Cosmotronic VPRTEX, Руководство пользователя

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LOW PASS FILTER
The non-resonant LOW PASS FILTER sections of both VCO1 and VCO2 are identical.
The filters have a 12dB/Oct slope which means that for every octave below the cut-off frequency (set
by the LOW PASS FILTER slider) the amplitude of the oscillator drops by 12dB. Setting the slider in the
top position keeps the VCO unaffected by the filter and setting it to the down position completely
attenuates the signal.
It’s possible to modulate the filter frequency with the SINE of VCO2 (normalized*). The knob is an
attenuator for this modulation. It’s also possible to use an external signal to modulate the filter by
patching a signal into the LPF input, breaking the internal normalization. The LPF input accepts bipolar
signals and the knob is an attenuator for this external modulation.
The maximum frequency is achieved (with the slider completely down) by sending 5V into the LPF
input (don’t forget to open the attenuator). This is really useful when patching an envelope into the
LPF input as most envelopes will be capable of opening and closing the filter completely.
Although this filter has a really basic feature set it provides for plenty of additional timbral shaping of
whatever is coming out of the MAIN output. While the filter is non-resonant it’s possible to make
throaty AM style sounds by modulating the frequency of the filter with a fast VCO (that’s FM of the
filter to create AM sounds).
On top of that it’s possible to get really interesting timbres by feedback patching the MAIN output back
into the LPF input (use a stackcable or a mult for this). There’s more detailed information about this
in the PATCH EXAMPLES.
b
VORTEX / Complex Oscillator 11
* The way most normalized
or
normalled connections
work is by using a little
mechanism inside the chassis
(female jack) that bends out
of the way when a jack is
inserted.
In the simplified diagram to
the left A is connected to B
when nothing is patched into
the
input. This is the
normalized connection.
When a jack is inserted into
the chassis the lug which is
connected to B is bent out of
the way and by doing so it is
disconnected from A. Instead
now the tip T of the jack is
connected to A.
ring
panel
tip
normalized
ring
panel
tip
normalized
G G
A B B A
R
T
T
R