These 6.5"ultimate sounding quality Bass-Midrange drivers have been designed to match advanced studio monitoring requirements for proximity monitoring. The exceptional sound accuracy of these units results from a careful design using A/B listening tests to select technological solutions, which authorizes their use up to 2.5kHz without any compromise, and up to 4.0kHz with full preservation of dynamic behavior (Compromise is on directivity pattern only). Optimum Bass-Reflex loading is situated between 12L and 16L tuned from 45Hz to 40Hz.