BQST

BQST is a mastering tone plugin built around a broad Baxandall-style EQ feeding a two-mode saturation stage. It is designed for subtle mix-bus and master-bus tone shaping: lift, weight, density, and controlled harmonic color without turning into a distortion box by default.

Portfolio writeup: https://rohanjk.xyz/projects/bqst

Download

Download BQST from the project page:

https://www.rohanjk.xyz/projects/bqst

The macOS installer includes:

• VST3: /Library/Audio/Plug-Ins/VST3/BQST.vst3
• Audio Unit: /Library/Audio/Plug-Ins/Components/BQST.component

Factory presets are built into the plugin. User presets can be saved from the plugin UI as .bqstpreset files.

Support

BQST is free to download. If it's useful to you and you want to support future development, you can buy me a coffee:

https://ko-fi.com/rohanjk

Features

• Bax-style low and high shelves with broad, low-Q curves.
• Independent side controls in L/R or M/S mode.
• Separate routing modes for the EQ and saturation sections.
• Cream and Grit saturation modes. Grit blends the original transformer-inspired curve with a model fitted to captures of an LA500A; older sessions keep the original Grit.
• Per-side Drive, Mix, and Output controls.
• Vintage top rounding after saturation.
• Static drive-based autogain calibrated from offline test material.
• Realtime and render oversampling up to 8x.
• VU-style output meters calibrated around 0 VU = -18 dBFS.
• Factory presets, user preset saving, and previous/next preset navigation.
• Fixed hardware-inspired UI with 75%, 100%, 125%, and 150% view sizes.

Formats

• macOS VST3
• macOS Audio Unit
• macOS Standalone app when building from source

Build From Source

Requirements:

• macOS
• CMake 3.22+
• Xcode or Apple command line tools
• JUCE checked out as the external/JUCE submodule

Clone with submodules:

git clone --recurse-submodules https://github.com/rohanz/bqst.git
cd bqst

Configure and build:

cmake -S . -B build-release -DCMAKE_BUILD_TYPE=Release
cmake --build build-release --config Release

Build artifacts are written to:

build-release/BQST_artefacts/Release/VST3/BQST.vst3
build-release/BQST_artefacts/Release/AU/BQST.component
build-release/BQST_artefacts/Release/Standalone/BQST.app

Additional developer build, validation, local install, and packaging notes are in docs/build-notes.md.

Validation

The release VST3 and Audio Unit builds have passed pluginval strictness level 10 during development. BQST has also been tested in Ableton for loading, UI interaction, parameter automation, preset recall, bypass behavior, sample-rate changes, fixed UI sizes, and offline render paths.

Documentation

• docs/manual.md: controls and workflow.
• docs/design.md: design and product direction.
• docs/build-notes.md: detailed build, packaging, signing, and validation notes.
• packaging/README.md: installer artwork and packaging notes.
• CHANGELOG.md: release notes.

License

BQST source code is licensed under GPLv3. See LICENSE.md and LICENSE-GPLv3.txt.

The BQST name, logo, UI artwork, installer artwork, website images, factory presets, screenshots, and related branding assets are reserved. See TRADEMARKS.md.