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V-VERB PRO REV2496
The LFO can be used to modulate feedback intensity. With
RESMOD
(LFO feedback modulation amount), you determine how
much LFO will affect the RESON(ANCE) parameter (EDIT page
1). Positive values result in feedback being increased as the
frequency increases; negative values result in feedback being
lowered as the frequency increases.
The LFO speed can also be modulated through the volume of
the input signal. The
LFOMOD
(envelope to LFO speed
modulation) parameter determines how much the LFO will be
influenced by signal strength. The
ATTACK
(attack time)
parameter controls how quickly the LFO speed is increased
when signal volume increases erratically.
HOLD
(hold time)
determines how long the LFO frequency should be kept constant
when the signal volume starts decreasing.
RELEAS
(release
time) determines how quickly the LFO frequency will be
decreased after the HOLD time expires.
4.9 Tremolo
This is a typical tremolo/panner algorithm with a couple of
interesting extra features built in.
Fig. 4.9: Design of the tremolo effect
SPEED
(modulation speed) determines modulation speed.
Entering this parameter via TAP makes this process very intuitive.
The
WAVE
(LFO waveform) parameter determines the wave
form for amplitude modulation. In doing so, the wave form can be
cross-faded from triangle-shaped (1) to sinusoidal (50) all the
way to square wave form (100). Editing the WAVE parameter is
much easier in the graphical editing mode. With
PHASE
(LFO
phase), you can set modulation phase length of the right channel
compared to the left channel. The available parameter range is
between -180° and +180°.
MIX
(effect mix) controls the depth of amplitude modulation.
GAIN
(output gain) lets you correct the output volume of the
effect block (engine).
The median LFO speed can also be modulated through the
input signal level. In doing so, the
LFOMOD
parameter (envelope
to LFO speed modulation) determines how strongly the LFO is
influenced by signal volume. The time parameters
ATTACK
(attack
time),
HOLD
(hold time) and
RELEAS
(release time) control how
quickly the LFO speed will increase when the signal volume
increases, how long it will be held and how quickly it will decrease
after the HOLD time expires.
4.10 Compressor
This is a very complex compressor algorithm with two basic
operating modes: peak compression and RMS compression. A
multimode filter side chain lets you use only certain frequency
ranges for calculating the control signal. Additionally, a crossover
is available for compressing only a certain segment of the
frequency spectrum. Its possible applications are the de-esser
and bass compressor/enhancer.
Fig. 4.10: Compressor design
The
ATTACK
(attack time) parameter determines the time that
the compressor needs to react to signals that exceed the signal
level set with THRESH(HOLD).
HOLD
(hold time) determines how
long the signal level is reduced after the signal volume drops
below the threshold value.
RELEAS
(release time) determines
how quickly the compression will ease up after the HOLD time
ends.
With
THRESH
(compression threshold), you can determine the
minimum signal level for deploying compression.
RATIO
(compression ratio) determines the compression rate once this
threshold is exceeded. The
KNEE
(soft knee) parameter can be
used to smoothen the curve changeover from an uncompressed
to a compressed signal. A value of 0 deactivates this function
(hard knee), and 10 produces maximum smoothening of the
curve. The GRAPH page indicates the compression line and the
signal level reduction.
With
M-GAIN
(make-up gain), you can correct the output
volume of the compressed signal.
With
LOOKAH
(look ahead delay), you can delay the audio
input relative to the side chain path. For example, this can be
used together with longer attack times because the side chain
has more time to lower the signal level, which can produce quite
interesting effects. Please note that this also delays the overall
output signal of your REV2496.
With
FILTER
(side chain filter mode), you can select the type
of side chain filter. When set to OFF, the filter is inactive.
Additionally, you can select one of these: LP12dB (low pass
filter with 12 dB decrease per octave), HP12dB (high pass filter
with 12 dB per octave), LO SHV (low shelving filter), HI SHV
(high shelving filter) and BP (band-pass filter). Depending on the
filter type you select,
FREQ
(frequency) determines the center
frequency of the filter.
GAIN
determines the level of the shelving
filters, and
Q
determines the bandwidth of the band-pass filter.
With the
MODE
(compression mode), you can select the basic
type of compression. PEAK measures the current, maximum
signal strength, while RMS detects the average signal energy. In
RMS mode, the length of integration window can be set to values
between 1 to 20 ms (milliseconds).
The transient bypass function gives you the option to exclude
the short-time transients from compression in the audio signal.
The
TRANS
parameter defines the maximum length of the
transients that will remain unaffected by compression.
4. EFFECTS
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