User Manual

THOR POLYSONIC SYNTHESIZER
(RECORD+REASON)
572
• Filters 1 & 2 can be used serially (i.e. the output of Filter 1 goes (via the Shaper) to the input of Filter 2, or in
parallel (meaning that one signal goes to Filter 1 and another to Filter 2).
The pre-defined routings of the three oscillators into the Filter 1-2 sections is described in the “Basic connections -
a tutorial” passage.
Common parameters
As with the open oscillator slots, there are certain parameters which are common for all filter types.
These are as follows:
D All the filter types have large knobs for the filter frequency (FREQ) parameter and the filter resonance (RES)
parameter.
This works slightly differently for the Formant filter - see “Formant filter”.
D The “KBD” parameter sets how the filter frequency tracks incoming note pitch data.
Some filter types (Ladder/State Variable/Comb) can “self oscillate” and be used as extra oscillator sources.
D The “ENV” parameter sets how much the filter frequency responds to the Filter Envelope.
D The “VEL” parameter sets how much incoming note velocity affects the Filter Envelope Amount.
In other words, for this parameter to have any effect it requires that the “ENV” parameter is set to a value other
than zero.
D The “INV” button inverts how the filter frequency responds to Envelope settings.
D The “Drive” parameter allows you to adjust the input gain to the filter.
By driving the filter harder you can add further character to the sound.
D Any parameter settings, as well as any modulation assigned to parameters, will be kept even if you change the
filter type.
Ladder LP Filter
The Ladder LP filter is a low-pass filter inspired by the famous voltage controlled filter patented by Dr. Robert Moog
in 1965. The name originates from the ladder-like shape of the original transistor/capacitor circuit diagram.
The original filter also had certain non-linear characteristics which contributed to the warm, musical sound it is re-
nowned for. These characteristics are faithfully reproduced in the Ladder LP filter.
There is also a built-in shaper in the feedback (self-oscillation) loop. If self-oscillation is activated (see below), the
shaper will distort the sound to produce these non-linear characteristics. To adjust the intensity of this distortion you
use the Drive parameter.
D There are 4 different Filter slopes available; 24, 18, 12 and 6 dB/oct.
24dB slope comes in two different types:
• Type I - The shaper (controlled with the Drive parameter) is placed at the filter output but before the feedback
loop.
• Type II - The shaper (controlled with the Drive parameter) is placed at the filter input after the feedback loop.