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ARTURIA – JUPITER-8V – MANUAL - EN
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7.1.3
The filter or VCF
The audio signal generated by an oscillator (the waveform) is next generally directed to a filter
module or VCF (
Voltage Controlled Filter
). It is this module that we use to control the sound by
filtering (by removing or subtracting certain frequencies, which explains the name given to this type
of synthesis) the harmonics situated around a cut-off frequency. It can be considered to be a
sophisticated equalizer that reduces, depending on the filter type, a range of frequencies of a
sound.
The removal of undesirable frequencies at the cut-off frequency is not done suddenly but
progressively, depending on the filtering slope. This filtering slope is expressed in decibels per
octave (or dB/Oct). Most filters used in classic analog synthesizers have 24 dB/Oct or 12 dB/Oct
slopes.
The Jupiter-8V offers several types of slopes
The removal of undesirable frequencies at the cut-off frequency
On the Jupiter-8V, you have access to a type of filtering with a 24 dB/Oct slope and to a type of
filtering with a 12 DB/Oct slope. Let’s have a look at some of its properties:
7.1.2.1
High Pass Filter (HP Filter)
The high-pass filter acts symmetrically to that of the low pass filter. It eliminates frequencies below
the cut-off frequency. The High-pass filter on the Jupiter-8V is non resonant.
Non resonant High Pass Filter
