Two Athens born tone machines serving clean precision and full stack chaos in one hit 🔥🎚️🎸
Crazy Tube Circuits has built a reputation for making pedals that feel crafted rather than produced. The Athens based team leans into character, detail and musicality, and it shows in both Phi Golden Ratio V2 and Heatseeker. They sit on opposite ends of the tonal world, yet share the same instinct for giving players more feel, more control and more of that hands on spark.
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Phi Golden Ratio V2 focuses on clarity and dynamic shape. It is a three voice analog compressor built to behave like a tiny studio tool. Each circuit inside it reacts differently. FET brings fast transients and a touch of colour. OTA locks into a familiar punch that feels controlled and direct. Optical smooths everything out with a warm, natural curve that stays musical even under heavy settings. These three voices live side by side and flipping between them is like changing the angle of a light.
Parallel compression is central to how Phi behaves. Blending dry and compressed signals fattens the tone without burying detail, which gives the pedal that subtle studio fullness that becomes hard to play without. An internal switch lets it run at 9 or 18 volts, opening up headroom and giving each mode a little more air. With its low noise floor and broad response, Phi fits just as easily on bass or in a recording chain as it does on a guitar board.
Heatseeker comes from a completely different lineage. It is built around a modern recreation of a seventies wireless preamp that became a quiet secret in rock rigs. The original unit expanded dynamics and added harmonic energy that made guitars pop. The new version keeps that flavour but folds it into a dual preamp pedal shaped by three British voiced amp models. It has the immediacy and growl associated with classic rock tone, but with more control than the original ever offered.
The preamp stage tightens lows and brings out the midrange while the Enhance control adjusts how aggressively the signal expands. It can add a slight sparkle or bring a tired sound back to life. The internal JFET circuit runs at 27 volts, giving the pedal genuine amp like behaviour with a wide clean to driven range. The three way switch moves between distinct British style responses, all tuned with their own gain structures and EQ curves.
WoS mode pushes things into another dimension. It widens the field, increases output and adds the kind of low end mass and high mid density associated with walls of heads and 4×12 cabs. The passive effects loop between stages gives the pedal even more flexibility, allowing external pedals to be placed inside the chain or enabling each side to run independently.
Together, Phi and Heatseeker show two sides of what Crazy Tube Circuits does best. One brings precision and softness. The other brings attitude and scale. Both feel musical in a way that comes from careful design rather than imitation.
TLDR
• Three voice analog compression with FET, OTA and Optical modes 🎚️
• Parallel blending for fat, clear studio style tone 🎧
• Switchable 9 or 18 volts for added headroom ⚡
• Dual preamp design inspired by classic seventies tone shaping 🔥
• Three British amp voices powered by high voltage JFET circuitry 🎸
• WoS mode for huge stack like scale and presence 💥
• Passive loop for flexible routing and rig building 🔁
