Design and Implementation of a 10-Band Parametric Equalizer Audio Plugin Using JUCE

This paper presents the complete design and implementation of a 10-band stereo parametric equalizer (EQ) audio plugin developed in C++ using the JUCE framework. The plugin employs a robust model-view separation using AudioProcessorValueTreeState for parameter management and features a 12-stage serial IIR filter chain per channel, including high-pass, low-pass, and peak filters. The work also integrates a non-linear tanh-based saturation module and a high-performance custom graphical user interface using sprite-sheet rendering techniques. The project serves as a case study in modern audio software engineering, combining digital signal processing theory with scalable, thread-safe architecture.