So that’s an unexpectedly scary video about a Eurorack module. People in dark robes wandering about in dark forests to the glitchiest deep dark tones of something evil. And then “BAM!” it’s Portal and it’s pissed and has lasers and stuff. Not your everyday product teaser trailer.
After a minute or two of unsettling madness the video settles down to a more familiar format of a module amongst a rack of other modules and we discover that Portal is all about movement. “Portal strives to move faster than it’s input and in doing so must travel back to the origin to begin its journey again.” Right, so it’s a bit like a wave folder where it multiplies the harmonics of a signal but instead of folding the wave over on itself the output jumps to zero (once a threshold has been reached) which creates a sharp transition almost as if the wave has travelled through a portal. Get it?
When applied to a triangle or sawtooth wave this creates a similar effect to sync but without need an additional oscillator. “When fed with complex audio sources the results are devastating, turning just about anything that goes through it into mad screams from another dimension.” Groovy!
There are three different flavours of simultaneous distortion and four control voltage inputs. The most important control is the Wrap knob that increases the number of times the signal is wrapped during one oscillator cycle. The Track control modulates how well the Wrap effect works. The Bias control is a DC offset to the input of the wrapping effect. It either introduces another signal before it’s wrapped or pushes the signal into clipping. Feedback feeds the output back into the input bypassing the Wrap VCA. These are all features of the Wrap distortion. The other two are Round and Spike. Round gives a staircase like an approximation of the wave a bit like a bit crusher but with analogue circuitry. Spike gives a tiny trigger whenever a new wrap or staircase is reformed by the other outputs giving a crackling version of the audio.
This thing is completely nuts. It’s a nasty, spiteful, crushing distortion that pulls waves apart and removes their souls. If you are in to harmonic distortion then this thing is for you. The rest of us probably need to go a lie-down and think of bunnies and puppies until the madness goes away.
Portal is available now for $295.
- Mystic Circuits webpage.