User Guide

SPACING:
The Spacing control is used to determine the difference between the cutoff
frequencies of the two filters in both dual lowpass mode and highpass/ lowpass
mode.
In Dual Lowpass mode, the numbers on the legend around the knob refer to
octaves. When the Spacing control is centered, the cutoff frequencies of the two
filters are identical and the filter sounds like a classic Moog Filter. Setting the Spacing
control to +1 in Dual Lowpass mode means that the right filter has a cutoff
frequency equal to where the Cutoff knob is set, and the left frequency has a cutoff
frequency that is one octave higher than the right filter. This means when the Cutoff
control is swept, two resonant peaks are heard, giving the filter a unique quality.
In Highpass/Lowpass mode, the Spacing control sets the difference between the
cutoff frequencies by shifting the highpass filter’s cutoff frequency up or down. When
the Spacing control is fully clockwise, the cutoff frequencies of the two filters are the
same, making for a very narrow frequency band.
RESONANCE:
The Resonance control causes feedback in the filter circuit that adds harmonic
emphasis at the cutoff frequency. This control affects the lowpass filters, but not the
highpass filter. When the Resonance control is all the way down, the lowpass filters
act as a tone control, rolling off high end as the Cutoff control is turned down. As
the resonance increases, the filter begins to form a peak at the cutoff frequency. As
the Cutoff control is swept the peaks reinforce the harmonics of the signal being
filtered are reinforced – creating an effect that is vocal or zappy. As the Resonance
is turned up the peak increases in strength until the control is set to 8 or higher, when
it begins to self-oscillate – creating sine waves with the same frequency as the
cutoff frequency.
KEYBOARD CONTROL AMOUNT:
The Keyboard Control Amount knob allows the Filter Cutoff to follow the key
played on the keyboard. A higher key will cause a higher cutoff frequency. This
allows a sound to retain its brightness as it is played higher on the keyboard.
FILTER CONTROL INPUT:
The Control Input on the back labeled FILTER is a CV input for external control of
the Voyager’s filter cutoff control. The Input accepts -5 to +5 volts, or an expression
pedal like the EP-1. The voltage applied here is added to where the front panel
Cutoff control is set. A one-volt change in this control voltage will change the cutoff
frequencies of both filters by about one octave.
FILTER POLES:
Each Filter’s Cutoff Slope can be changed. Select 1 pole (6 dB/Oct.) 2 pole (12
dB/Oct., 3 pole (18 dB/Oct.) or 4 pole (24 dB/Oct.). This can be done in EDIT mode,
with the items “Filter A Poles” and Filter B Poles”.