The MUSE 218SA is a high-output, ground-stacked subwoofer engineered to deliver extended low-frequency performance in professional sound reinforcement environments. Equipped with dual 460mm B&C long-excursion woofers and a robust 4000W Class D amplifier, the MUSE 218SA is capable of generating sound pressure levels up to 148.5dB. This makes it a reliable low-frequency extension for the MUSE 210LND line array, particularly effective in touring, live event, and fixed installation settings requiring consistent, high-energy bass response. Its bass-reflex cabinet is carefully optimised using BEM acoustic simulation to minimise turbulence and resonance, enhancing clarity and efficiency down to 30Hz. Designed for versatility, the MUSE 218SA includes factory presets enabling cardioid configurations that reduce rearward SPL by more than 15dB, offering greater control in acoustically sensitive environments. Built from 18mm birch plywood and finished with a durable black coating, the enclosure includes six integrated handles and optional caster fittings for improved handling and deployment. A heavy-duty front grille with protective fabric ensures long-term component integrity. With its combination of precise engineering, acoustic power, and configuration flexibility, the MUSE 218SA plays a vital role in delivering controlled, high-impact low-frequency reproduction in demanding professional audio applications.