Nexus XL 21" Low-Frequency Loudspeaker 2000W Black/RedThis low frequency enclosure expands upon the five resonant chamber theory, as used in the ever popular Stasys X (a dual 18 low frequency enclosure serving as the backbone of many Void Acoustics installations around the world). Further refining the design principle has led to previously unimagined levels of performance. Transient response and articulation were the two main design criteria. The use of a large transducer has provided exceptionally high