HIGHPASS LOWPASS MODE
:
In Highpass/Lowpass mode, the Voyagers filters are configured as a lowpass and
highpass filter in series, summed to both outputs. As with the dual lowpass mode,
the Cutoff control changes the cutoff frequency of both filters, and the spacing sets
the frequency difference between the highpass filter and lowpass filter. The spacing
between the two filters creates a bandpass filter (figure 21). The Resonance control
affects only the lowpass filter, thus making for some terrifically interesting filter
sounds.
CUTOFF
:
The Cutoff knob is the main filter control. This sets the cutoff frequency of both of
the filters in the both dual lowpass and highpass/lowpass mode.
In Dual Lowpass, the frequencies to the right of the indicator on the knob are the
frequencies that are filtered out. The frequencies to the left of the indicator are the
frequencies that are allowed to pass through the filter. This is why as you turn the
control clockwise the cutoff frequency becomes higher and the sound becomes
brighter. Of course to hear the effect of a lowpass filter it helps to have a signal rich
in harmonics which provides high frequencies to filter. A good example of a sound
rich in harmonics is a sawtooth waveform.
In Highpass/ Lowpass mode, the combination of highpass and lowpass filters
forms a bandpass filter. The Cutoff control changes the center frequency of the
passband.
