Iris (2018)' source signal was a 'thermal drift' - a slowly varying residual field generated by a mysterious resonance in my computer hardware, which had failed to be annihilated by the absorption term in a finite element simulation. The signal of drifting height values was modeled in real-time using the C++ Elementary Sinusoidal Modeling software alluded to elsewhere (see Tech), and the model then drove live resynthesized output into air, which was captured by a phone, and then polished using the spectral editing software Spear.