I’ll start with the title. I recently rewatched the TV series Halt and Catch Fire (one of my all-time favorites), which takes place at the dawn of home computing, networking, and the infancy of the internet. Throughout the series, there are a number of occasions where one character asks another “Have you ever worked close to the metal?” — in other words, have you ever really worked with computers, in a hands-on way — or they dismiss someone who has no real experience with computers as someone who has “never been close to the metal.” (I have never been close to the metal; I await Donna Clark’s contempt.)
This patch doesn’t really have a lot to do with computers or “computer music” (which I think of as a specific genre as fairly ridigly sequenced)! But the phrase stuck with me and as I was listening to the distorted wails the patch does produce and I kept thinking of metallic sounds and… there we are.
The patch consists of two synth voices. Both are composed of two sine wave oscillators, with one of the sine waves being randomly detuned from the other. For one voice (Voice 1), an envelope is applied to the pitch of the second oscillator, which raises it a fifth. For the other voice, one of the oscillators’ duty cycles is modulated. But otherwise, they are identical and relatively simple, just oscillators and a VCA. Both use long, slow envelopes, whose lengths are randomly determined, to control the VCAs. Their pitch is drawn from a D hirojoshi scale across a fairly wide range (four octaves or so), but it probably could have been unquantized and there would be little difference — this patch isn’t really about melody.
There is also a “noise burst” voice that creates all sorts of sounds by sending noise through a low-pass filter with its frequency and resonance randomly calculated, then passed through a VCA with a heavily modulated sine wave LFO modulating the gain.
So, the synth voices are pretty basic, but the effects chain is where the patch gets interesting. The first stop is a compressor where the noise bursts can sidechain the synth voices. The output of the compressor is sent into a delay, then the delay, compressor and noise bursts end up in a high-pass filter, which randomly changes its frequency and resonance. The high-pass filter goes into an overdrive module, which has its gain modulated. The frequencies picked up by the HPF are really pushed into the overdrive, which creates sort of pseudo-feedback sounds at times, menacing thuds at other times, and all sorts of distorted sounds. Finally, to tame some of high end, the overdrive goes into low-pass filter, which has its frequency modulated by three different sine wave LFOs.
At the end is a reverb lite, which has its decay and mix modulated as well. Modulation all over the place on this patch, which produces a lot of different tones and textures.