Access Virus Rack XL User Manual page 36

36
CHAPTER 5
Introduction
PHASER
The Phaser effect produces resonant (or even
cutting) emphasis on certain frequencies within
the signal. The frequencies of these resonances
are shifted around the frequency spectrum,
causing a distinctive movement in the sound.
Tastefully applied, this effect is particularly good
for pad sounds and for authentic traditional
electric piano sounds.
The pure Phaser signal is the result of a fre-
quency-dependent phase shift together with a
slight pitch modulation from the phaser's own
LFO. Typical phaser sounds only appear when
the processed signal is mixed with the dry sig-
nal, usually at the same level. The TYPE/MIX
control is used to set this balance.
The INTENSITY control changes the level of
feedback in the phased signal. Higher feedback
levels cause higher resonant peaks in the sig-
nal. The FEEDBACK parameter is bipolar, be-
cause positive and negative feedback have
different characteristics.
More phaser parameters can be found in the
EDIT menu: RATE and DEPTH control the
speed and intensity of modulation from the
phaser's own LFO. The other three parameters
affect the general sound of the phaser: FRE-
QUENCY determines the average frequency of
resonant peaks, STAGES is the number of reso-
nant peaks and SPREAD is the distance be-
tween resonant peaks within the frequency
spectrum.
THE CHORUS/FLANGER EFFECT
Another function that delivers great effects
based on pitch fluctuation is the so-called cho-
rus effect. Chorus actually consists of a brief
delay (generally up to approx. 50 ms) which is
varied periodically. By modulating the delay, the
delayed signal is slightly detuned to the input
signal (the so-called Doppler effect). This incon-
sistency in pitch between the original and ef-
fects signal is the source of the chorus effect.
Feedback in the delay line enhances this effect.
The left signal side is automatically modulated
in a different manner than the right, so a chorus
effect is great for converting mono signals into
stereo signals.
If the delay is less than approx. 10 milliseconds,
than the effect is called flanging or a flanger ef-
fect rather than chorus. In this case feedback is
even more significant because it generates res-
onances that can be modulated and is thus yet
another source of radical sound effects. If you
determine high feedback values, you can clear-
ly hear how the two sides of the signal are mod-
ulated differently - in reverse phase - by the
LFO.
Locate the parameter group CHORUS in the
EFFECTS menu.
01111111111111111112
1 CHORUS
Dir/Eff
61111111111111111154
CHORUS DIR/EFF determines the balance be-
tween the original signal and the processed sig-
nal. The parameters RATE and SHAPE control
another LFO that was installed specifically for
the chorus LFO. DELAY is used to set the delay
time, DEPTH determines the modulation inten-
sity, and FEEDBACK controls the feedback lev-
el. When you want to generate a flanger effect,
the FEEDBACK parameter's negative control
range lets you dial in softer characteristics for
the flanger. Please keep in mind that the Chorus
section in the Virus is fully stereophonic: Stereo
positions as well as panorama modulations and
stereo spread values that you have dialed in
elsewhere remain intact in the effects signal.
OFF≤