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Table Of Contents
A Brief LFO Overview
LFO is an abbreviation for low frequency oscillator. As the name suggests, this is an
oscillator, much like the three main oscillators of the ES2, but it differs in the following
ways:
An LFO generates signals below the audio frequency range—in the bandwidth that
falls between 0.1 and 20 Hz, but sometimes as high as 50 Hz.
Because it can’t be heard, an LFO only serves as a modulation source for periodic,
cyclic modulation effects—rather than as part of the actual audio signal.
For further information, see Synthesizer Basics.
Using ES2 LFO Waveforms
The LFO 1 Wave buttons allow you to choose different waveforms for LFO 1. The table
below outlines how these can affect your sounds.
Try using the waveforms while a modulation routing of Pitch123 (the pitch of all three
oscillators) is engaged and running.
CommentsWaveform
Well suited for vibrato effectsTriangle
Well suited for helicopter and space gun sounds. Intense
modulations of the oscillator frequencies with a negative (inverse)
sawtooth wave lead to “bubbling” sounds. Intense sawtooth
modulations of lowpass filter cutoff and resonance creates rhythmic
effects. The waveform can also be inverted, resulting in a different
start point for the modulation cycle.
Sawtooth
Use of the rectangular waves will periodically switch the LFO
between two values. The upper rectangular wave switches between
a positive value and zero. The lower wave switches between a
positive and a negative value set to the same amount above/below
zero. An interesting effect can be achieved by modulating Pitch123
with a suitable modulation intensity that leads to an interval of a
fifth. Choose the upper rectangular wave to do so.
Rectangle
The two lower waveform settings of the LFOs output random values.
A random value is selected at regular intervals, as defined by the
LFO rate. The upper waveform steps between randomized
values—rapid switches between values. At its lower setting the
random wave is smoothed out, resulting in fluid changes to values.
The term Sample & Hold (S & H) refers to the procedure of taking
samples from a noise signal at regular intervals. The values of these
samples are then held until the next sample is taken.Tip: A random
modulation of Pitch123 leads to an effect commonly referred to as
a random pitch pattern generator or sample and hold. Try using
very high notes, at very high rates and high intensities—you’ll
recognize this well-known effect from hundreds of science fiction
movies!
Sample & Hold
82 Chapter 5 ES2