Waldorf PPG Wave 2.V, Руководство по эксплуатации

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PPG Wave 2.V
Waldorf 30 Operation Manual
CV
CV is an abbreviation for Control Voltage. Analog synthesizers use an analog voltage to
control sound parameters like pitch, filter frequency etc. Modulations, caused by
control voltage, can be created both in systems that use fixed element groups and in
systems where element groups can freely and directly be connected. if you e.g. wish to
create a Tremolo effect, then the output signal of an LFO must be modulated onto the
control voltage of one (or several) oscillators.
Decay
Parameter of an Envelope. Means the sinking speed of the Envelope, which starts di-
rectly after the Envelope has reached its maximum amplitude value. The Decay phase
starts directly after the Attack phase. It ends when the Envelope reaches its hold level
that is set with the Sustain parameter.
Envelope
An Envelope creates a control signal that changes against time. It is used to modulate a
sound shaping element within a given period of time. An Envelope can for instance
modulate the filter corner frequency of a low pass filter. Dependent on the Envelope,
the filter opens and closes, which changes the characteristics of the filtered sound a-
gainst time. A trigger signal – often a MIDI note – starts the Envelope. The classic En-
velope form consists of four separately adjustable phases: Attack, Decay, Sustain and
Release. For this reasons it is called ADSR Envelope. As soon as a trigger signal arrives,
the Envelope starts its travel through the Attack- and Decay-phases until it reaches the
Sustain level. This is then held for as long as the trigger signal lasts. Thereafter the En-
velope starts its Release-phase, which lowers the level to its minimum value.
Filter
The filter is one of the most important sound shaping elements within a synthesizer.
The PPG Wave 2.V has a low pass filter with resonance capability, as it could be
found in the classic analog synthesizers. A low pass filter attenuates frequencies above
a certain corner frequency, and the Resonance (in the PPG called Emphasis) emphasi-
zes a narrow frequency range around the corner frequency.
Filter Frequency
The filter frequency is an important parameter of filters. A low pass filter attenuates sig-
nal components above this frequency. Signal components, that occur below this, can
pass and are not processed.
Gate
In audio engineering, the term Gate is used in different ways. Its basic character is al-
ready expressed in its name. It can be opened and closed, or technically speaking, ac-
tive or inactive. A Gate as a device is a group of elements, which let a signal pass or
not. Which of the two, is determined by certain given conditions. In a noise gate this
principle is used to suppress noise in signal pauses. It only lets signals pass, that have a
defined minimum level. In the field of analog synthesis, a Gate is a control signal,
which can have both states: active inactive. The keyboard of such a synth can be used
as an example: When you press a key, the keyboard sends two different signals: CV
and Gate. The control voltage (CV, see above) defines the pitch of the pressed key. The