BPB Dirty Filter is a free tube distortion effect designed to shape and color your audio with ease. It features two resonant filters that target specific frequency ranges, allowing precise control over which part of the sound spectrum is affected. This focused approach helps enhance or alter your audio without overwhelming the entire signal, making it suitable for creative sound design or subtle tonal adjustments.

The plugin offers a straightforward workflow where you select the frequency band to distort and adjust the Drive control to introduce tube saturation and resonance. When the Drive parameter is set to zero, it functions as a clean filter that can effectively remove unwanted low-frequency hum or high-frequency noise from your mix. Increasing the Drive beyond halfway transforms it into a powerful distortion tool, capable of adding rich harmonic content while preserving the original audio with the Mix control.

BPB Dirty Filter includes high-pass and low-pass filters with adjustable slopes, giving you flexibility in shaping your sound’s frequency response. It supports multiple plugin formats including VST2, VST3, AU, and AAX, and works on both Windows and macOS systems in 32-bit and 64-bit modes. This makes it an accessible and effective addition to any music production setup, offering tonal enhancement and distortion without cost.