The Loud Professional Push Loop™ Technology represents a step forward in the lower frequency response compared to the traditional direct radiating vented box. Based on the Push-pull loading technique, this special compound design combines three different techniques: Push-pull, Band-pass, and Horn Loading system, All-in-one!It provides an exceptional low frequency extension down to 22 Hz, along with the better sound definition, reducing three times the total harmonic distortion in a really compact enclosure no larger than a typical single 21in. subwoofer system.The pair of 21in. transducers, in a cone-to-magnet isobaric configuration, act like a single driver doubling the power handling (3000 + 3000 Watts Program) with a much larger motor resulting in more control of the woofer linear excursion. They also provide lower frequency response compared to a single 21in. Vented design. Same time the Band-pass system produces significant benefits in terms of high efficiency and deepest bass extension that would not be possible in conventional designs of equal size. The Band-pass also allows a greater control over cone motion and upper low end region, even significantly reducing the total harmonic distortion (THD). The third technique applied, the Horn Loading system, combines the above mentioned effects with the high system efficiency in terms of a greater wavefront output (SPL), giving a sensitivity of 106 dB (2.83 V @ 1 m). Very impressive low frequency extension, for a massive sound impact, can be produced from the extremely compact F221 enclosure. All-in-one for a unique subwoofer system as you never heard before. A dolly (three-units) and the skate (single-unit) make easier and faster all transpositions. Significant construction criteria, combined with the latest technologies and innovative materials, ensure a great reliability over time. The Formula Sub F221 cabinet is constructed from marineBirch-ply and has an impact and weather protected PCP (Polyurea Cabinet Protection) finish.
It can be as well matched with all the most challenging Loud Professional Full-Range and Line-Array systems, significantly boosting their LF extension.

Applications: Large Open Air Venues, Arenas, Stadiums, Theaters, Conference Halls, Concert Halls, Large Scale Discos & Clubs.