The KS21 is a compact reference subwoofer designed to extend the bandwidth of A15 and A10 systems.

L-Acoustics KS21 features one high excursion, direct radiating 21" transducer mounted in a bass-reflex tuned enclosure.

The KS21 is also available in install-specific versions, KS21i, KS21iW, and KS21iRAL, with the latter two featuring white or RAL coating of the enclosure.

When coupled with A15 system, the KS21 operates from 39 Hz to 60 Hz, whereas when working with A10 that changes to 30 Hz and 100 Hz.

To ensure reduced turbulence and port noise at high level, the KS21 features L-Vents that additionally increase LF efficiency.

KS21’s frequency response has been optimised to work seamlessly with both systems.

In terms of rigging, the KS21 features a two-point, integrated rigging system that is compatible with A15, meaning that various combinations of KS21 and A15 can be flown or stacked to form a full range line source.

Additionally, KS21 can work in a pole-mount configuration with A15 or A10, as it has an integrated threaded insert.

KS21 can be deployed in standard or cardioid configurations with dedicated presets for flown and stacked deployment.