20
The LFO Section
Peak has four Low Frequency Oscillators (LFOs), denoted LFO 1 to LFO 4. The
parameters of LFO 1 and LFO 2 are immediately user-adjustable via a full set of top panel
controls. The parameters of LFO 3 and LFO 4 are accessed via the LFO menu: these two
LFOs are available for routing to other parts of Peak through the Modulation Matrix.
LFO 1 and LFO 2 hardware controls
15 16 17 18
LFO 1 and LFO 2 are identical in terms of features, but their outputs may be directly routed
using the panel controls to different parts of the synth and are thus used differently, as
outlined below:
LFO 1:
• can modify the waveform shape of each oscillator when LFO1 is selected by the
oscillator’s Source button
13
;
• can modulate the filter frequency; the amount of modulation is adjusted in the Filter
Section with LFO 1 Depth control
40
.
LFO 2:
• can modulate the pitch of each Oscillator; the amount of modulation is adjusted
in the Oscillator Section with the LFO 2 Depth control
12
. This is the method of
adding “vibrato” to a sound.
Either LFO may additionally be patched in the Modulation Matrix (see page 26) to
modulate many other synth parameters.
LFO Waveform
The Type button
15
selects one of four wave shapes - Triangle, (falling) Sawtooth,
Square or Sample and Hold. The LEDs above the button confirm the waveform
currently selected.
LFO Rate
The speed (or frequency) of each LFO is set by the Range button
17
and the rotary Rate
control
18
. The Range button has three settings: High, Low and Sync. The LFO frequency
ranges are from 0 to 200 Hz in the Low setting and 0 to 1.6 kHz in High. Selecting
Sync reassigns the function of the Rate control, and allows the speed of the LFO to be
synchronised to an internal or external MIDI clock, based on a sync value selected by the
control. When Sync is selected, the OLED displays the RateSync parameter, which
allows you to choose the tempo division required with the Rate control. See LFO Sync
Rate table on page 37.
LFO Fade Time
LFO effects are often more effective when faded-in, rather than just ‘switched on’; the
Fade Time parameter sets how long the LFO output takes to ramp up when a note is
played. The rotary control
16
is used to adjust this time. See also Fade Mode
(page 21), where you can also make the LFO fade out after the Fade Time, or, start or
end abruptly after the Fade Time.
The LFO Menu
LFO1 and LFO 2 are ‘per voice’. This is a very powerful feature of Peak (and other Novation
synthesisers). For example, when an LFO is assigned to create vibrato, and a chord
is played, each note of the chord will be varied at the same rate, but not necessarily at
the same phase. There are various settings in the LFO Menu that control how the LFOs
respond and lock together.
LFO 1 and LFO 2 each have three menu pages; the parameters available for LFO 1 and
LFO 2 are identical.
As LFO 3 and LFO 4 are intended for the creation of additional modulation effects rather
than fundamental tone generation, they are ‘global’ as opposed to ‘per-voice’. They have
one menu page each; the parameters available for LFO 3 and LFO 4 are identical.
The default menu displays for LFO 1 are shown below:
LFO 1 1/8
MonoTrig Legato
Phase Free H
Slew 0
LFO 1 2/8
FadeMode FadeIn H
Common Off
Fig. 11
FadeSync On
LFO 1 3/8
Fig. 12
Repeats Off H
LFO 1 1/8
MonoTrig Legato
Phase Free H
Fig. 10
Slew 0
LFO 1 2/8
FadeMode FadeIn H
FadeSync On
LFO 1 3/8
Fig. 12
Repeats Off H
LFO 1 1/8
MonoTrig Legato
Phase Free H
Fig. 10
Slew 0
LFO 1 2/8
FadeMode FadeIn H
Common Off
LFO 1 3/8
Repeats Off H
LFO Phase
Displayed as: Phase
Initial value: Free
Range of adjustment: Free; 0deg to 357deg (in 3deg increments)
Each LFO runs continuously ‘in the background’. If Phase is set to Free (the default),
there is no way of predicting where the waveform will be when a key is pressed.
Consecutive presses of a key will inevitably produce varying results. With all other values
of Phase, the LFO will re-start at the same point on the waveform every time a key is
pressed, the actual point being determined by the parameter value. A complete waveform
has 360º, and the control’s increments are in 3º steps. Thus a half-way setting (180deg)
will cause the modulating waveform to start at half-way through its cycle.
KEY "ON"
KEY "ON"
PHASE = 0
O
PHASE = 90
O
PHASE = 180
O
KEY "ON"
MonoTrig
Displayed as: M o n oTrig
Initial value: Legato
Range of adjustment: Legato or Re-Trig
M o n oTrig only applies to monophonic Voice modes (see “Voices” on page 27).
Providing that LFO Phase is not set to Free, the LFOs are re-triggered each time a new
note is pressed. But if you are playing in legato style (literally “smoothly” – playing further
keys while one key is still held), the LFOs will only re-trigger if M o n oTrig is set to Re-Trig.
If set to Legato, you will only hear the effect of re-triggering on the first note.