MODIFIERS & CONTROLLERS
Doc Q7.0
141
Program Change Reset
7.2.5
Normally, the last value of an external control source is retained—even across preset changes—until a new value is
received. So if you “park” a pedal-controlled Wah, for example, then change to a new preset with the same Wah
settings, the newly loaded preset will load with the Wah in the same parked position.
Program Change Reset
(
PC RST
) allows you to
override
this behavior, causing a parameter to use a previously
stored setting when it loads, rather than referring to the retained source value. As soon as the external controller
is updated—the pedal moved, a new MIDI message received—the attached parameter snaps back to track it again.
Here’s how it works: the parameter box above a modified knob always shows the “reset” value so you can freely
set and save it. Note: Knob and filter “graph” parameters with modifiers are animated as their sources change, so
you won’t see graphical elements update in the display as you turn the value wheel. You can either set the stored
value before turning
PC RST
to ON or change it afterwards. Note: Internal controllers (q.v.) are not subject to
PC RST
because their values are updated immediately when a preset loads.
Control Sources
7.3
LFO1 & 2
7.3.1
An
LFO
, or Low-Frequency Oscillator, generates control signals in the form of a variety of
familiar wave shapes or random signals. Familiar examples of LFOs in action include the
pulsing of a tremolo, the steady back and forth sweep of a phaser, or the modulation of a
chorus. The Axe-Fx II contains two global LFOs that can be individually programmed per-preset for use as modifier
sources to control various other parameters. Press the front panel
button to find the LFO1 and LFO2
menu pages for the current preset.
Each of the two LFOs outputs two signals (A and B), so the list of modifier sources contains four entries: LFO 1A,
LFO 1B, LFO 2A, and LFO 2B. By default, A/B pairs are complementary, meaning that as A swings from 0–100, B
swings from 100–0, but the phase of output B is fully adjustable for in-phase or in-between settings.
Besides being available as a modifier source, LFO1 may also be used to SYNC the rates of the Chorus, Flanger,
Phaser, Tremolo, and Multi-Delay blocks. This not only allows the sweeps of these effects to be aligned to each
other, but to other modifiers as well. Set the “native” rate fully counterclockwise to enable LFO1 SYNC.
TYPE
– This sets the waveform or shape of the selected LFO.
RUN
– Tucked into the MODIFIER slot beneath the TYPE control, this parameter starts and stops the LFO.
When the LFO is stopped, its output drops to “zero,” and the wave cycle resets. When using a MIDI CC via an
external controller to toggle RUN, a value of 70 or higher will START the LFO, and a value of 57 or lower will
STOP the LFO (assuming the modifier has default settings for
MIN/MAX/START/MID/END/SLOPE
).
Tip:
An LFO that is locked to tempo can still “drift” from another system or device. To stay locked to “song position,” just stop
and restart periodically from your DAW/sequencer with a quick pair of OFF/ON messages sent at regular intervals.
RATE
– Sets the frequency of the LFO from 0.05–30.0 Hz. When
RATE
is shown in parenthesis, it is being
controlled by the tempo parameter (below). Set
TEMPO
to “NONE” for manual control.
