GateKeeper Docs
MULTA FILTER
This is my take on the classic 1974 12db filter. Its four modes will have significantly different characteristics compared to modern versions. In my opinion it’s pointless to design a part for part recreation of something that already exists. So with that in mind I made some changes.
Characteristics:
The MULTA filter is fairly aggressive and “dirtier” than the 4072 filter. A slight bit of resonance is always present and adds to the sparkle. But it is slightly darker than the 4072.
The MULTA IN potentiometer is an active gain feeding into the filter. Depending on the gain setting the characteristics can change.
As you increase the MULTA RESONANCE the RED LED will indicate the intensity.
LOW PASS Fairly traditional It can filter down to zero cycles completely silencing the audio signal.
MODDED BAND PASS has a little more bite than the original. The curve is not as extreme at the top end as the original. This gives it a blunter feel. There will be a low frequency bump when the MULTA FILTER knob gets to about 5 o’clock and then a drop as it inverts to the other direction.
Pro Tip: Using your Gate triggered ASDR in combination with the MULTA CV potentiometer you can exploit this sweet spot. Turn MULTA filter all the way down and feed in enough envelope to open the filter only within this range. You’ll get a very interesting texture.
HIGH PASS works much like you would expect but when paired with the DIST modes can produce some unexpected results.
DIST FB OSC PASS is the most unconventional. It’s producing a feedback loop with a clipped signal feed back into itself. It’s almost a Low Pass with a lot of distortion at some positions.
There is definitely a tipping point where the chaos can abruptly kick in. Pair this with the DISTORTION 3 position. Some modes will produce self oscillation.
CAUTION: When you start to add in extreme resonance with various filter positions and ADSR envelopes paired with the distortions and modded positions conventional responses no longer apply. Your GateKeeper will respond in many unexpected ways. Especially if you are not running sequenced material through it. Personally I’ve been working with the prototypes for a year now. There are still times things surprise me. Some places I may never get back too. If you can always record experimentations.
If you can, always record your experimentations.