Operation Manual

SUBTRACTOR SYNTHESIZER
191
The Filter Section
In subtractive synthesis, a filter is the most important tool for shaping the overall tim-
bre of the sound. The filter section in Subtractor contains two filters, the first being a
multimode filter with five filter types, and the second being a low-pass filter. The com-
bination of a multimode filter and a lowpass filter can be used to create very complex
filter effects.
Filter 1 Type
With this multi-selector you can set Filter 1 to operate as one of five different types of
filter. The five types are illustrated and explained on the following pages:
D 24 dB Lowpass (LP 24)
Lowpass filters lets low frequencies pass and cuts out the high frequencies. This
filter type has a fairly steep roll-off curve (24dB/Octave). Many classic synthesizers
(Minimoog/Prophet 5 etc.) use this filter type.
The darker curve illustrates the roll-off curve of the 24dB Lowpass Filter. The lighter curve in the
middle represents the filter characteristic when the Resonance parameter is raised.
D 12 dB Lowpass (LP 12)
This type of lowpass filter is also widely used in analog synthesizers (Oberheim,
early Korg synths etc.). It has a gentler slope (12 dB/Octave), leaving more of the
harmonics in the filtered sound compared to the LP 24 filter.
The darker curve illustrates the roll-off curve of the 12dB Lowpass Filter. The lighter curve in the
middle represents the filter characteristic when the Resonance parameter is raised.
D Bandpass (BP 12)
A bandpass filter cuts both high and low frequencies, while midrange frequencies
are not affected. Each slope in this filter type has a 12 dB/Octave roll-off.
The darker curve illustrates the roll-off curve of the Bandpass Filter. The lighter curve in the middle
represents the filter characteristic when the Resonance parameter is raised.