The active, modular subwoofers are equipped with high-efficiency Class-D amplifiers. Developed by Harmonic Design, the built-inhd MultiDSP with FIR/IIR filter technology allows phase-coherent adjustments between tops and subwoofers, and thanks to its numerous features, guarantees a well-balanced and homogenous sound at any volume. Harmonic Designs uncompromising presets use FIR filters and GroupDelayCorrection to ensure linear playback in even the most diverse applications. The user can use the built-in signal processing tools (EQ, delay, etc.) to make individual settings and save as a preset. The Harmonic Design Systems are in rough, everyday use perfect and reliable tools for sound engineers, DJs, musicians, artists and rental companies with linear and undistorted sound reproduction.