DuckEQ is an equalizer that responds dynamically to side chain input, functioning as a ducker targeting specific frequency bands. It also operates effectively as a traditional ducker or a dynamic equalizer, providing flexible control over audio signals. This unique combination allows for precise frequency-focused gain reduction or enhancement, making it a powerful tool for mixing and broadcast scenarios.

This plugin is particularly useful for managing overlapping frequency content between instruments such as bass and kick drum or vocals and electric guitars. Unlike standard broadband ducking, DuckEQ’s frequency-selective approach enables users to duck only certain frequency ranges, preserving the clarity of other elements in the mix. Beyond ducking, the plugin offers creative possibilities such as applying gain boosts to specific bands, effectively creating an 'EQ-Gate' effect that adds dynamic tonal shaping.

While compressors with side chain inputs can perform similar tasks, DuckEQ offers more consistent and predictable gain reduction, especially when ducking elements like guitars from vocals. It reduces gain uniformly, independent of signal loudness, avoiding the variable attenuation typical of compressors. The plugin is open source and free to use under the GNU General Public License v3. Users should note that the VST version may have interface issues, and feedback is encouraged to improve stability and performance.