The sound of analog.
Without the cost.

Eurorack hardware, circuit-accurate plugins, and sample packs — designed and built in Seattle.

Shop the new modules What we do
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The Open Source Series

Four all-analog 6HP Eurorack modules from the celebrated CC0 designs of Super Synthesis — sequencer, scanner, envelope, and VCA, in production here in Seattle.

PHRSR Eurorack module — front panel and PCB

PHRSR

6HP

Two-channel 1–16 step knob recorder / sequencer. Records knob movements, plays them back as CV.

From $50 Shop →
SCANNER Eurorack module — front panel and PCB

SCANNER

6HP

Takes 0–5V in, outputs four overlapping triangular CVs. Feed it a saw, get quadrature triangles.

From $50 Shop →
EG Eurorack module — front panel and PCB

EG

6HP

All-analog voltage-controlled Attack-Decay envelope generator with End Of Cycle trigger output.

From $50 Shop →
TVCA Eurorack module — front panel and PCB

TVCA

6HP

Two-input VCA built around the LM13700 OTA, with a distortion path that exploits its tanh transfer function.

From $50 Shop →
$50 PCB + Panel SMD parts pre-soldered
$75 Full DIY Kit Every component included
$99 Assembled Built & tested in Seattle

Original designs by Chris McDowell of Super Synthesis, released under CC0. We keep them in production. See all hardware →

What we do

Analog, three ways.

One philosophy: honest sound at a fair price. Simulated, sampled, or built — pick your path.

01

Hardware — built

Small-batch Eurorack modules, pedal-format utilities, and aluminum cases — designed, machined, and assembled in our Seattle workshop. Open standards, no collector markup.

Eurorack · Pedals · Cases Shop hardware →
02

Plugins — simulated

Wave Digital Filter emulations modeled component-by-component from the original schematics, on our open-source PedalKernel engine. Perpetual license, no iLok.

Pedals · Amps · Studio Shop plugins →
03

Sample packs — recorded

Tracked through the actual gear in our Seattle room — real synths, real preamps, real iron. 24-bit / 48 kHz, royalty-free, instant download.

24-bit / 48 kHz · royalty-free Shop sample packs →
The technology

Wave Digital Filters, from the schematic up

WDF is a physical-modeling technique from classical network theory, introduced by Alfred Fettweis in the 1970s. Every component in a circuit becomes a wave-scattering element, wired in the exact topology of the original schematic. Our plugins are built from the circuit diagram — not from recordings of one unit on one afternoon.

  1. 01

    Trace the schematic

    We start from the original circuit diagram and service documentation. Every resistor, capacitor, diode, and gain stage goes into a netlist — nothing is approximated by ear.

  2. 02

    Model each component

    Each part becomes a wave-domain element with the physics of the real one: capacitors store charge over time, diodes clip, tube and transformer stages stay nonlinear at audio rate.

  3. 03

    Rebuild the network

    Series and parallel adaptors reconnect the parts in the original topology, so voltages and currents obey the same Kirchhoff laws they do on the bench.

  4. 04

    Solve it in real time

    The whole circuit runs sample-by-sample on PedalKernel, our open-source engine — so it responds to pick attack and guitar volume the way hardware does.

screamer.pedal PedalKernel DSL →
pedal "Tube Screamer" {
  components {
    R1: resistor(4.7k)
    C1: cap(220n)
    D1: diode_pair(silicon)
    Gain: pot(500k)
  }
  nets {
    in -> C1.a
    C1.b -> R1.a, D1.a
    D1.b -> gnd
    R1.b -> Gain.a
    Gain.b -> out
  }
  controls {
    Gain.position -> "Drive" [0.0, 1.0] = 0.5
  }
}

This is real source from the PedalKernel README: components with their actual values, the nets that wire them, and a panel control bound to the pot’s position. The engine compiles it into a real-time WDF processor — turn Drive and the clipping point moves because the 500 kΩ pot moved, not because we crossfaded between snapshots.

The literature

WDF isn’t a marketing word — it’s 40 years of peer-reviewed signal-processing research. The engine is built on it.

  1. A. Fettweis. “Wave Digital Filters: Theory and Practice.” Proc. IEEE, vol. 74, no. 2, pp. 270–327, 1986.
  2. K. J. Werner, V. Nangia, J. O. Smith, J. S. Abel. “Resolving Wave Digital Filters with Multiple/Multiport Nonlinearities.” Proc. DAFx-15, Trondheim, 2015.
  3. K. J. Werner. “Virtual Analog Modeling of Audio Circuitry Using Wave Digital Filters.” Ph.D. dissertation, Stanford University (CCRMA), 2016.
  4. J. Chowdhury. “chowdsp_wdf: An Advanced C++ Library for Wave Digital Circuit Modelling.” arXiv:2210.12554, 2022.
From our bench: What is WDF? → WDF vs. convolution & neural models → PedalKernel — the engine source →

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