Catalyst Audio - Mig Thruster

Catalyst Audio's MIG Thruster is an all-analog, voltage-controlled noise source for Eurorack, built around the 1J24b — a Soviet subminiature pentode originally made for the Cold War Mikoyan-Guyverich (MiG) fighter jets. Rather than handing you a clean, anonymous hiss, it gives noise a personality, and a slightly volatile one at that. The tube sits in the middle of the circuit doing the work, not bolted onto the output, so what you hear is the tube itself misbehaving in useful ways.

The main controls — Mixture, Throttle and Pressure — are deliberately hard to translate into standard synth language, and read more like something referring to a small engine. Catalyst are upfront that these don't line up with familiar module controls; they nudge internal tube behaviour and bias voltages, and they're deeply interactive, so the way to learn them is to turn them and listen. Low Cut is a 12dB high-pass that reshapes the character of the noise as it filters, not just trims the bottom, and the Resonance control can swing that character around quite dramatically. A Range switch flips between flavours of noise, subtle or drastic depending on where everything else sits.

Throttle, Pressure and Low Cut each get a CV input with an attenuverter, so the whole thing animates nicely under modulation. The flip side of that enormous range is that you can also dial it into silence — push Pressure or Resonance far enough and it just stops. No fault, just the territory; a sweep of the Res knob usually finds the noise again. Good as raw noise, a layer of grit under drums, or an unruly signal to set other modules moving, all in all — an unusual and deeply unique sound source!

Features:

• All-analog, voltage-controlled vacuum tube noise source
• Built around the 1J24b NOS (New Old Stock) Soviet subminiature pentode
• Tube at the heart of the circuit, not added at the output
• Mixture, Throttle, Pressure and Low Cut controls
• Low Cut: 12dB high-pass that also shapes the noise character
• Resonance control over the low-cut filter
• Range switch for different noise flavours
• Internal feedback pathways
• CV inputs with attenuverters for Throttle, Pressure and Low Cut
• Single main output