Looking for testers for FreeEQ8 — open-source JUCE/C++ parametric EQ plugin

General JUCE discussion
1

Hey JUCE devs,

I’m looking for testers and technical feedback on FreeEQ8, an open-source JUCE/C++ equalizer plugin I’ve been building.

FreeEQ8 is a free parametric EQ plugin focused on clean DSP architecture, modern plugin workflow, and cross-host compatibility. The project is built with JUCE/CMake and is intended to be a practical open-source EQ codebase for producers, engineers, and developers interested in audio plugin development.

Current feature direction includes:

  • Multi-band parametric EQ workflow

  • Analyzer / spectrum display direction

  • M/S processing architecture

  • Dynamic EQ direction

  • Linear-phase / advanced filter-processing direction

  • Oversampling / quality-mode planning

  • Preset and parameter recall

  • Host automation support

  • Cross-platform VST3/AU-style plugin structure

  • Production-focused documentation and test planning

The main thing I need right now is real-world testing across DAWs and systems:

  • Does it build cleanly?

  • Does it scan/load in your host?

  • Does the UI open correctly?

  • Does audio pass correctly?

  • Do presets and parameters recall properly?

  • Does automation behave as expected?

  • Any crashes, CPU spikes, denormals, UI lag, or pluginval/auval failures?

Repo:
https://github.com/GareBear99/FreeEQ8

Tester issue / feedback:
https://github.com/GareBear99/FreeEQ8/issues

I’m especially interested in reports from Reaper, Ableton, Logic, FL Studio, Bitwig, Cubase, Studio One, and pluginval/auval testing on macOS, Windows, and Linux.

I’m a solo dev building this in public, so even a simple compatibility report like “built on Windows / loaded in Reaper / pluginval result attached” would be extremely helpful.

Thanks to anyone willing to test or give feedback.

2

Does it build cleanly?

:skull:

3

Nice.

From your DSP implementation section:

"Coefficient Calculation: RBJ Audio EQ Cookbook"

At the very least I’d swap these out for the SVF formulas that Andy Simpler did for EQ8 in Ableton.

Very commonly used these days over RBJ and easy to find c++ source code for if you search - even on these forums.

Also worthy of consideration as a direct replacement of RBJ for an EQ:

Here you have fully de-cramped filters. No need for oversampling unless you want to preserve phase at higher frequencies. MIT license with full single .h source code (naming oddity: ‘Midshelf’ is actually ‘Peak’ filter). Also comes with the magnitude response which is handy for plotting.

It’s more in line what you’d expect from a commercial EQ these days.

Both are extremely stable under modulation.

4 Likes