The Geiger Macro
Geiger Counters are used to measure ionizing radiation, such as in radiological protection, experimental physics and the nuclear industry (so says Wikipedia, you might be able to tell that I’m not a physicist!). You would have heard the sound in any post apocalyptic or cold war paranoid era film about a nuclear fall-out.
Reaktor 5 actually has a module dedicated to replicating this sound (left). The information from the manual says it “generates events at random intervals, much like a Geiger Counter radiation particle detector”. To understand this it’s useful to understand radioactive decay, which Wikipeida describes as:
…a stochastic (i.e. random) process at the level of single atoms, in that, according to quantum theory, it is impossible to predict when a particular atom will decay. The chance that a given atom will decay never changes, that is, it does not matter how long the atom has existed.
Mind-numbing eh? Oddly, inside the Geiger macro we don’t see the Geiger primary module that Reaktor supplies. Instead we have a trigger generator similar to a Geiger Counter module but with slightly more flexibility. We have input terminals for P, Rnd and Dyn, and a simple output terminal that leads to ADR envelope.
P is controlled by the Density knob on the front panel while Rnd (random) and Dyn (Dynamic) which have been described above. There are two Randomize modules. P is added to the output of one of these. This in turn receives part of its input from a pulse that is driven by said the other Randomize module.
The LFO’s rate is determined by the P value. This is a logarithmic value converted to linear frequency. This outputs a pulse wave – perfect for triggering envelopes. This is run into an A to E Trig module which converts an audio event into an event output. Phew!
Let’s fire up SpaceDrone in Ableton Live and get some big ‘ole ambient pads moving. I’ve tweaked the default preset, moving the Fundamental to 60 (MIDI note C3 or C4 depending on who you believe), increased the resonance and pan, reduced the dampening and slowed the speed right down.
I next brought the reverb mix down a little (in the ‘B’ view). I’ve just added some EQ and compression too. Nothing special so far.
Adding Live’s Resonator tuned to a C minor 7 chord (C, Eb, G, Ab) gives us a nice Tanpura-like quality to it (you can read about some more awesome stuff to do with Live’s Resonator here). I’ve disabled the input filter, increased the decay and set it to 70% wet.
I’ve added some SoundToys Crystallizer (using the Phillip Glass Echoes preset) and some Valhalla Shimmer. I’ve finished the sound off with a dulling low-pass filter to send it right back in the mix. Feels like dropping acid on the Floating Islands level on Tomb Raider II (without all the gunshots, though).