10. Glossary
4-Pole
Describes the number of individual filter components in an VCF
(refer to the appropriate section). Each pole is capable of damping
the signal’s frequencies higher than the filter corner frequency by
6dB per octave, respectively. Consequently, a 4-pole filter
dampens the signal by 24dB per octave. The volume of a signal
that is an octave higher than the filter cutoff frequency would be
24dB lower when it remains unfiltered. This signal would no
longer be audible.
Amount
Describes to which extent a modulation influences the given
parameters. This term is used in the System Exclusive data format
to describe a value.
Attack
Describes the ascent rate of an envelope (refer to the appropriate
section) from its starting point to the point where it reaches its
highest value. The attack phase is initiated immediately after a
trigger is received. For the 4-Pole, the attack is defined as a rate
value (refer to the appropriate section).
Cutoff
Describes the cutoff frequency, in other words the frequency at
which the filter begins to dampen the signal’s frequencies that lie
above this cutoff frequency. A lowpass filter dampens the
frequncies above the designated cutoff frequency. The
frequencies that are lower than the cutoff frequency remain
unaffected. The filter cutoff frequency can also be emphasized
via resonance (refer to the appropriate section).
Decay
Describes the descent rate of an envelope once the attack phase
(refer to the appropriate section) has reached its zenith and the
envelope drops to the level defined for the sustain phase. For the
4-Pole, the attack is defined as a rate value (refer to the
appropriate section).
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