HFN 2006

Exceptionally tall speaker engineer Karl-Heinz Fink, and his more diminutive partner Lampos Ferekedis, stand each side of their remarkable prototype BMR technology demonstrator (balanced-mode radiator; see the December 2005 Stereophile). These two, forming a "gang of four" with original inventor Dr Graham Bank and marketing man John Vizor, have licensed the BMR technology from NXT, and the prototype, using a 3.4" BMR unit upwards from 400Hz, via an active crossover, clearly showed the considerable potential of this radical driver, which in effect automatically reduces the radiating diameter as frequency rises.

A complete absence of the usual 2–4kHz crossover lobing artefacts, and wide dispersion to the very highest frequencies were clearly and gratifyingly audible at the company's Hi-Fi News Show demonstration. Indeed, the wide dispersion of this little BMR unit posed a significant design problem in making baffle-edge diffraction effects that much more obvious, the solution combining a wide baffle with a considerable physical driver offset, on both the baffle and a black felt blanket.