19
CHORUS AND FLANGE
Both choruses and flangers use a Low Frequency Oscillator (LFO) to produce their rich, swirling effects.
When you change the speed and depth Parameters of modulation effects, you're actually controlling the
frequency and amplitude of the LFO. These settings determine the rate and intensity of the modulation
effect.
In general, here's how choruses and flangers work: after entering the Module, the source signal is split
into two paths. One is allowed to pass through the Module unaltered, while the other is delayed and pitch
modulated. The modified sound is then sent to the output, along with the original. In Fig. 3-3 below, a sine
wave is used to modulate the pitch of the split sound source.
Figure 3-3 Modulation Example
The Dual Chorus creates two different pitch “voices”, while the Octal Chorus creates eight voices for
extremely full, rich sounds.
The only difference between choruses and flangers is that flangers use less delay and have a feedback
Parameter that sends a portion of the effected signal back to the input of the Module. When the effected
signal reaches the input, it is sent through the Module again, building thickness and depth. If you increase
the feedback enough, the source begins to lose its own original pitch to the dramatic pitch modulation of
the feedback loop.
L F O W a v e f o r m s : There are four LFO waveforms available for Choruses, Flangers, Phasers, Tremolos,
Auto Panners, and five for Modifier LFOs. They include SINe, TRIangle, SPecial-1, SPecial-2, and SPecial-
3. See figure 3-4 for examples of what these waveforms look like.
Figure 3-4 LFO Types
FREQUENCY (SPEED)
AMPLITUDE (DEPTH)
SINE LFO
FREQUENCY (SPEED)
AMPLITUDE (DEPTH)
TRIANGLE LFO
FREQUENCY (SPEED)
AMPLITUDE (DEPTH)
SP1 LFO
FREQUENCY (SPEED)
AMPLITUDE (DEPTH)
SP2 LFO
FREQUENCY (SPEED)
AMPLITUDE (DEPTH)
SP3 LFO
(Modifiers only)
PITCH
T I M E
-5 cents
0
5
cents
10
10
1 sec
2 sec
3 sec
Modulated Sound
Original Sound
Section 3 - Effects and Parameters
Studio 400 Owner's Manual
