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Sound

The DSP engine.

One small library of sound blocks: gate, EQ, limiter, cabinet and tuner.

The DSP engine's source

A bar chart of the processor cost per sample of each DSP blockLive

What it does

The same code runs on a laptop, a Raspberry Pi and a microcontroller.

Who it’s for

Anyone building audio gear, in software or in hardware.

Why we built it

So what you hear in a demo is what the pedal does.

What we’re proud of

The tuner, the effects and the cabinet share one engine.

Try it

The live piece

The engine, on every machine

LiveCPU cost per block, by block sizeOpen full
Text version: squatch-dsp CPU cost per block, by block size
squatch-dsp CPU cost per block, by block size (ns per sample, Apple M1 Max, 48 kHz) (ns per sample)
blockblock 16block 32block 64block 128
limiter52.4552.7251.951.39
gate4.834.754.784.77
eq (3 bands)6.368.3210.711.98
gate + eq + limiter70.1465.5868.1170.22
tuner134.78134.24134.68134.28
cabinet (200 ms IR)80.8881.1680.8681.09
LiveOne DSP core, four hostsOpen full
Text version: One DSP core, four hosts

squatch-dsp: each block is written once and runs everywhere

  1. Blocks · written once (group) leads to Raspberry Pi
  2. Blocks · written once (group) leads to Microcontroller ESP32-S3 · Cortex-M7
  3. Blocks · written once (group) leads to Browser WebAssembly
  4. Blocks · written once (group) leads to Desktop plugins
  5. C++17, real-time safe: no allocation, locks, I/O or throws in the audio path leads to Blocks · written once (group)

Our sound tools

Where each one runs.

One open sound engine under all four. Each is free, with its source on GitHub.

The Squatch plug-ins

Ten effects for your DAW, as Audio Unit, VST3 and CLAP.

  • MacOut nowSigned by us and notarized by Apple.
  • WindowsComingx64 and ARM64 in v0.3.0, unsigned at first. Tested offline in a Windows DAW on a Windows 11 ARM64 virtual machine; not yet tried live or on real audio hardware.
  • LinuxPartlyThe core sound library, no plug-ins yet.

Squatch Tuner

A strobe tuner that reads a string to a tenth of a cent.

  • BrowserOut nowtuner.squatch.cc, on a computer or a phone.
  • MacOut nowA command-line tuner, notarized, for Apple silicon.
  • LinuxOut nowThe command-line tuner for x86 and ARM.
  • WindowsComingThe command-line tuner, in the v0.3.0 release with the plug-ins.

The DSP engine

The sound blocks under all of these, in one small C++ library.

  • MacOut nowA static library for Apple silicon.
  • LinuxOut nowA static library for x86-64.
  • BrowserOut nowAs WebAssembly, inside the rig.

Technologies used

What it’s built with.

More work

Keep looking.

A flow diagram from a circuit netlist to a plugin, compared against a simulator referenceMeasuredCaptureInteractive

A circuit model held to its reference.

Our sound models, compared against a circuit simulator.

The Squatch Tuner, a strobe display reading a guitar stringLiveCaptureInteractive

The tuner locks in 44 ms.

A guitar tuner for your browser and the pedal.

Measured

The number that didn't hold up.

Where the same model is off by 9.5 dB.

All the work

Get in touch

Want something like this? Say hello.

A person reads every message.

Email [email protected]
Text us

Text us: +1 888-344-3607. You text first; we reply only in that conversation, about your question. No marketing. Msg & data rates may apply. Reply STOP to opt out, HELP for help. SMS program

Our goods: store.squatch.ccThe studio: squatch.cc