ZL Equalizer

ZL Equalizer is an equalizer plugin.

Build from Source

Install Dependencies

Please make sure Clang (AppleClang 16+ or LLVM/Clang 17+), cmake 3.25+, ninja are installed and configured on your OS.

On Linux, you can install the remaining dependencies with the following command:

sudo apt-get update && sudo apt install libasound2-dev libx11-dev libxcomposite-dev libxcursor-dev libxext-dev libxinerama-dev libxrandr-dev libxrender-dev libfreetype-dev libfontconfig1-dev libxi-dev

Clone and Build

Once you have set up the environment, you can clone the ZL Equalizer code, populate all submodules, then configure & build the code. Please set:

• the variable ZL_JUCE_FORMATS as a list of plugin formats that you want, e.g., "VST3;LV2"
  • AAX plug-ins need to be digitally signed using PACE Anti-Piracy's signing tools before they will run in commercially available versions of Pro Tools.
• the variable ZL_EQ_BAND_NUM as the number of bands, default 24 bands
  • The plugins built with different ZL_EQ_BAND_NUM may NOT be compatible with each other.
• the variable ZL_HWY_STATIC_TARGET as the SIMD target
  • If you are on x86-64 and your CPU supports SSE2, set ZL_HWY_STATIC_TARGET=SSE2.
  • If you are on x86-64 and your CPU supports SSE2/SSE4, set ZL_HWY_STATIC_TARGET=SSE4.
  • If you are on x86-64 and your CPU supports SSE2/SSE4/AVX2, set ZL_HWY_STATIC_TARGET=AVX2.
  • If you are on arm64, set ZL_HWY_STATIC_TARGET=NEON.
• If there are multiple compilers on your OS, you may need to pass extra flags to maker sure that cmake uses LLVM/Clang.
  • On Linux, you may pass -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++.
  • On Windows, you may pass -DCMAKE_C_COMPILER=clang-cl -DCMAKE_CXX_COMPILER=clang-cl.

git clone https://github.com/ZL-Audio/ZLEqualizer
cd ZLEqualizer
git submodule update --init --recursive
cmake -B Builds -G Ninja -DCMAKE_BUILD_TYPE=Release -DZL_JUCE_FORMATS="VST3;LV2" -DZL_HWY_STATIC_TARGET="NEON" .
cmake --build Builds --config Release

After building, the plugins should have been copied to the corresponding folders. If you want to disable the copy process, you can pass -DZL_JUCE_COPY_PLUGIN=FALSE, find the binary folders under Builds/ZLEqualizer_artefacts/Release and copy them manually.

AI Transparency

Since October 2026, LLMs have assisted across various stages of this project's development. All code, documentation, and design choices are either authored or reviewed by the maintainer, who takes full responsibility for the quality, safety, and licensing of the final output.

License

ZL Equalizer is licensed under AGPLv3, as found in the LICENSE.md file. However, the logo of ZL Audio and the logo of ZL Equalizer are not covered by this license.

Copyright (c) 2023-2026 zsliu98

JUCE framework from JUCE

JUCE template from pamplejuce

nlopt by Steven G. Johnson

Highway by Google

Material Symbols by Google

inter by The Inter Project Authors

References

Yuriy Ivantsov. On the Ideal Bilinear and Biquadratic Digital Filter. (2025).

Yuriy Ivantsov. On the State Space of a Linear Digital Filter. (2025).

Cleve Moler. Makima Piecewise Cubic Interpolation. MathWorks Blogs. (2019).

Nigel Redmon. Cascading filters. (2016).

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Martin Vicanek. Matched One-Pole Digital Shelving Filters. (2019).

Martin Vicanek. Matched Second Order Digital Filters. (2016).

Aaron Wishnick. Time-Varying Filters for Musical Applications. DAFx. (2014).