The Sonance Blaze Audio BL218SSi is a dual 18-inch high-output sub-bass companion subwoofer housed in a tour-grade enclosure for the most demanding professional production applications. Two 18-inch drivers in a single cabinet provide the extended low-frequency extension and headroom required for large-format music reinforcement, high-SPL dance environments, and arena-class touring rigs.

The tour-grade construction handles repeated transport, rapid setup, and rigorous load-in and load-out without compromising acoustic performance. The black cabinet is color-matched to the broader Blaze Audio production loudspeaker family, making the BL218SSi a natural choice when a single 18-inch sub doesn't have the throw, output, or low-frequency extension required by the venue.

The dual-18 configuration delivers SPL and bandwidth beyond what a single-18 sub can provide — the right answer when a single BL118SSi isn't enough for the venue. Stage one BL218SSi per side of the rig for symmetric coverage, or fly multiple cabinets in cardioid configurations to control low-frequency directivity in larger venues.