Using Perl to simulate a numbers station

On the Disquiet Junto Slack, one of our members posted that they’d had a dream:

I had a dream about a piece of gear last night. I wouldn’t say that it was “dream gear,” though it was still cool. It was a small black metal box, about the size of three DVD cases stacked on top of each other. There were a few knobs and sliders, a small 3-inch speaker, headphone out, and a telescoping antenna, so it kinda looked like a little radio at first. The antenna was there for radio reception but there was other stuff going on. It was intended to be used as a meditation/sleep aid/ASMR machine. There were sliders for a four-band EQ and a tuning knob for the radio. The tuning knob had a secondary function that tuned a drone sound (kinda sounded like a triangle wave fed through a wavefolder/resonance thinger). The other feature of this box was something like a numbers stations generator. Another slider was for the mix between the drone and a woman’s voice speaking random numbers and letters from the NATO alphabet in a Google Assistant-/Alexa-/Siri-type voice but with far less inflection. The four-band EQ was to be used like a mixer as well in that it was how a person could adjust how much of the radio signal was audible over the drone/numbers by using the output gain of the EQ. There was also a switch that fed the drone/numbers signal into the EQ as well. The EQ was intentionally low-quality so that when you took it above 0dB, it would distort.

The Disquiet Junto Slack, #gear channel

Now what was weird was that I’m been doing something like this in AUM; I had a quiet ambient Dorian sequence driven by ZOA on several instances of KQ Dixie (a DX7 emulator), and was using Radio Unit (a radio streaming AU) to layer in some birdsong. I realized I could mostly emulate the dream box if I added another Radio Unit to pull in some random stations, but generating the “numbers station” audio was more of a challenge – until I remembered that OS X has the say command, that will let you use the built-in speech synthesizers to pronounce text from the command line.

I sat down, and after some fiddling (and looking up “how to add arbitrary pauses” so the rhythm was right), I created NATO::Synth to create the strings I wanted and pass them to say. It has a few nice little tweaks, like caching the strings created so it can decide to repeat itself, and properly inflecting the start and end of each “sentence”.

I saved the generated audio (recorded with Audio Hijack) to iCloud, loaded it into AUM, and then recorded the results. Very pleased with it!