Radical BMR Drivers Make Cambridge Audio’s Minx System Different & Better

Posted by: Chris Martens at 5:05 pm, February 16th, 2011

• No need for midrange-driver-to-tweeter crossovers: a BMR driver as used in the Cambridge Audio Minx satellite speakers can and does cover both midrange and treble frequencies, so that no crossover network is needed. At their present state of development, BMR drivers can handle everything from lower midrange frequencies on up, so that a traditional woofer—a small powered subwoofer in the case of the Minx system—is still required. But who knows what future development possibilities BMR technology might hold?
• No dispersion problems: a BMR driver does not “beam” as frequencies climb higher and higher; on the contrary, dispersion remains broad and evenly balanced from the bottom of its range to the top. This is true because the transition to ripple-mode operation allows even fairly large diameter drivers to disperse well—even at extremely high frequencies.
• No phase or timing problems: a BMR stays in phase with itself (well, plus or minus a bit as in any drive unit) across its entire operating range. What is more, there are “lobing” effects to contend with as in normal multi-driver speakers with separate, dedicated midrange and tweeter drivers.

Put all of these factors together, as Cambridge Audio has done in the Minx system, and you have the recipe for a compact system that can produce an unusually big and sophisticated sound.

Just consider this: until the Minx system came along, the only other firm to apply BMR drivers in a high-end audio context was Naim Audio, which uses BMR drivers in its brilliant Ovator-series floorstanding loudspeakers. Having heard Naim’s Ovators, I can vouch for the fact that they sound terrific, but they are also relatively large and expensive (the top Ovator models cost many thousands of dollars per pair). What’s exciting to me about the Minx rig is that, by design, it makes the advantages of BMR technology accessible in compact format and at Everyman prices.

Stay tuned for a full review of the Cambridge Minx S325 system in an upcoming online issue of The Perfect Vision.