User manual

4.6 The LFO Module 40
frequency of the oscillator is fixed relative to the frequency (tempo) of the master clock (see 4.12.1)
and the value displayed in the Sync control. Sync values range from 1/8 of a quarter note (a thirty-
second note) to 16 quarter notes (4 whole notes) where the duration of the whole note is determined
by the value (in BPM) appearing in the Tempo display of the Clock module. The LFO module can
also be synced to a triplet (t) or a dotted note (d). Note that when the Sync control is depressed, the
Rate knob has no effect.
4.6.3 Phase and Reset Mode
The LFO module behaves in a polyphonic way which means that a low frequency oscillator is
associated with each voice of the polyphony. This allows the LFO module to control notes played
on the keyboard individually. The gate signal received from the keyboard is used to reset the LFO
waveform when a note is played on the keyboard. The specific point in the waveform where the
LFO module will start generating signal is determined by the position of the Phase knob and
whether or not the LFO is in reset mode.
The reset mode is enabled by clicking on the Reset button. In this mode, the phase of the output
signal of the LFO corresponding to a polyphonic voice is fixed and adjusted with the Phase knob.
This means that every time a note is depressed on the keyboard and a gate signal is received from
the Keyboard module, the LFO module will start generating signal for this specific voice starting
at a specific point in the cycle of the waveform. The initial phase of the signal is determined with
the Phase knob which enables one to select values over a full period of the waveform. The value
of the phase lag is increased by turning the knob clockwise and is equal to 0, 180 degrees and 360
degrees when the knob is in its leftmost, center and rightmost positions respectively. This feature
enables, for example, the triggering of filter sweeps or panning effects that always start at the same
point every time a note is played.
When the LFO is not in Reset mode (Reset button off), the phase of the signal is random and
determined within a range fixed by the Phase knob. Turning this knob clockwise will increase the
range to values located at different point of the wave period as explained above. The main interest
of this mode is to keep voices uncorrelated when chords are played. Indeed, the LFO modulation
signals corresponding to the different voices will then start at different points even if all the notes
are triggered at the same time. Note that when the LFO module is not in Reset mode and the
Phase knob is fully turned to the left (phase of 0 degree), the synthesizer behaves as if the LFO
was monophonic and all the voices played were following this single LFO.
4.6.4 Fade-In
One more feature of the LFO module is the possibility to add a fade-in effect to its output signal.
The duration of this fade-in can be adjusted within the range of 0 to 5 seconds, as determined by
the Fade knob. Turning this knob fully to the left results in a value of 0 which is equivalent to
removing the fade-in effect. The time at which the LFO signal is introduced can even be controlled
by adding a delay to the fade in. This parameter can also be set to values varying between 0 and 5