Attack
Operation Manual
32
Waldorf
Cutoff
See Filter Cutoff Frequency.
CV
CV is the abbreviation for control voltage. In analog synthesizers, control voltages are
used to control sound parameters like pitch, cutoff frequency etc. To get a tremolo ef-
fect, for example, the output signal of a LFO must be routed to the CV input of one or
more oscillators.
Decay
"Decay" describes the descent rate of an envelope once the Attack phase has reached
its zenith and the envelope drops to the level defined for the Sustain value.
Envelope
An envelope is used to modulate a sound-shaping component within a given time fra-
me so that the sound is changed in some manner. For instance, an envelope that mo-
dulates the cutoff frequency of a filter opens and closes this filter so that some of the
signal's frequencies are filtered out. An envelope is started via a trigger, usually a fixed
trigger. Normally, the trigger is a MIDI note. The classic envelope consists of four indi-
vidually variable phases: Attack, Decay, Sustain and Release. This sequence is called
an ADSR envelope. Attack, Decay and Release are time or slope values, and Sustain is
a variable volume level. Once an incoming trigger is received, the envelope runs
through the Attack and Decay phases until it reaches the programmed Sustain level.
This level remains constant until the trigger is terminated. The envelope then initiates
the Release phase until it reaches the programmed minimum value.
Filter
A filter is a component that allows some of a signal's frequencies to pass through it and
dampens other frequencies. The most important aspect of a filter is the filter cutoff fre-
quency. Filters generally come in four categories: low pass, high pass, band pass, and
band stop. A low pass filter dampens all frequencies above the cutoff frequency. A high
pass filter in turn dampens the frequencies below the cutoff. The band pass filter allows
only those frequencies around the cutoff frequency to pass, while all others are dampe-
ned. A band stop filter does just the opposite, i.e. it dampens only the frequencies a-
round the cutoff frequency. The most common type is the low pass filter.
Filter Cutoff Frequency
The filter cutoff frequency is a significant factor for filters. A low pass filter, for example,
dampens the portion of the signal that lies above this frequency. Frequencies below this
value are allowed to pass through without being processed.
Gate
The term "gate" has different meanings in a technical context. Like a real gate, it descri-
bes something that can be open or closed, or - to use a technical term - active or inac-
tive. A gate in the sense of a device is a unit that prevents a signal from passing through
under specific conditions. For example, in a noise gate a signal is cut off when its level
falls above a predetermined threshold. Gate stands also for a control signal of analog
Summary of Contents for Attack
Page 1: ......
