Oberheim Matrix-12 - Page 113

Low Pass
High Pass
Band Pass
Notch
Phase
High + Low
Notch + Low
Phase + Loin
Low Pass Modes
1 POLE LOW
2 POLE LOW
3 POLE LOW
4 POLE LOW
The Low Pass modes filter out the higher harmonics of the
VCOs. In other words, these modes let the low frequencies
"pass" through. As an example, a low FREQ setting will only
allow a few of the total harmonics available pass though.
Higher settings pass more of the harmonics.
The number of poles determines at what rate the highs are
attenuated (filtered out) and this facet VCF operation is
discussed in just a moment.
High Pass Modes
1 POLE HIGH
2 POLE HIGH
3 POLE HIGH
The High Pass modes operate just the opposite of Low
Pass. They filter out the low harmonics of the VCOs and let
the high frequencies pass through.
Band Pass Modes
2 POLE BAND
4 POLE BAND
The Band Pass modes combine the filtering operation of the
Low Pass and High Pass filters. They filter out the extreme
highs and extreme lows, letting only a band of harmonics in
the middle pass through.
Notch Mode
2 POLE NOTCH
The Notch or Band-Reject mode functions the opposite of
the Band Pass modes. Instead of passing harmonics in the
mid frequencies, it filters this band out and passes the
extreme highs and lows.
Phase Shift Mode
3 POLE PHASE
This mode is unusual because it lets all of the VCOs
harmonics pass through the Filter, but changes the relative
phase of the harmonics as they pass through. As the
frequency (FREQ) of the VCF changes, it shifts the phase.
Using an Envelope or an LFO to change the VCFs
frequency is a good way to observe how this phase shifting
affects the sound. In fact, if the the VCFs Frequency is not
changing, you may observe very little difference in the sounds
even as differrent settings of FREQ are used.
Matrix-12 Owner's Manual
113