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Table Of Contents
Chapter 15 EFM1 179
LFO
The LFO (Low Frequency Oscillator) serves as a cyclic modulation source for FM
Intensity or Vibrato. Turning the LFO control clockwise increases the effect of the LFO
on FM Intensity. Turning it counter clockwise introduces a vibrato.
In the center (0) position the LFO does not have an effect. You can easily center the LFO
dial by clicking on the 0.
Rate
The speed/rate of the LFO cycles is set with the Rate parameter.
The Output Section
The EFM1 provides several level controls, as discussed below.
Sub Osc Level
For added bass response, the EFM1 features a sine wave sub oscillator. This operates
one octave below the FM engine (as determined by the Transpose parameter). Turning
up the Sub Osc Level control mixes the sub oscillator sine wave with the EFM1’s FM
engine output.
Stereo Detune
Stereo Detune adds a rich and diverse chorus-like effect to the sound of the EFM1. This
is achieved by doubling the EFM1 voice with a detuned second FM engine. The
amount of detune is adjusted using the Stereo Detune dial. A wide stereo effect is also
added, increasing the space and width of your sound.
Vol(ume) Envelope
The volume envelope shapes the overall volume contour. The volume envelope
consists of four sliders: Attack time, Decay time, Sustain level, and Release time. The
volume envelope is triggered every time a MIDI note is received. The Attack slider
defines the time needed to reach the maximum volume level. The Decay slider sets the
time needed to reach the Sustain level (as determined by the Sustain slider). The
Sustain level is held until the MIDI note is released. The Release slider controls the time
needed to reach a volume level of zero, after the MIDI note has been released.
Main Level
The Main Level control adjusts the overall output level of the EFM 1. Turning it clock-
wise makes the EFM1 output louder. Turning it counter clock-wise will decrease the
output level.