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Glossary – Waldorf 2-Pole User Manual

Page 30

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Appendix

2-pole Analog Filter User´s Manual

30

Glossary

Amount

Describes to which extent a modulation influences a
given parameter.

Amplifier

An amplifier is a component that influences the volume
level of a sound via a control signal. This control signal is
often generated by an envelope or an LFO.

Band Pass Filter

A band pass filter allows only those frequencies around
the cutoff frequency to pass. Frequencies both below and
above the cutoff point are damped.

Decay

"Decay" describes the descent time 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 com-
ponent within a given time frame so that the sound is

changed in some manner. For instance, an envelope that
modulates 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 individually
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 recei-
ved, the envelope runs through the Attack and Decay
phases until it reaches the programed Sustain level. This
level remains constant until the trigger is terminated. The
envelope then initiates the Release phase until it reaches
the minimum value.

Filter

A filter is a component that allows some of a signal's
frequencies to pass through it and dampens other fre-
quencies. The most important aspect of a filter is the filter
cutoff frequency. Filters generally come in four catego-
ries: 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 fre-
quencies below the cutoff. The band pass filter allows
only those frequencies around the cutoff frequency to