The Calipers' dynamic range and bass handling qualities are squarely in the mid-sized monitor class of speakers. Like their British brethren, the Calipers have a smooth, transparent midrange, are laid back in their presentation, and do wonderful things for human voice. Unlike most of the monopole Brits, however, the Calipers throw a huge, solidly 3D soundstage. This is a result of the Calipers' dipolar design. A dipole speaker fires its sound front and rear, but the sonic backdraft is out of phase with the front, causing cancellation lobes that effectively cancel out sound at the Apogee's sides.
Quads are also dipoles.
A true bipole, like the Mirage speakers, on the other hand, radiates its sound all in phase, and in a spherical pattern. True bipolars are therefore more 'spacious' in their sound, but are also more susceptible to side wall reflections than a dipole. The 3D spaciousness of the Caliper's soundstage is one of its strongest points, and lends it a greater sense of realism. There are those who will object to this type of presentation, preferring a more tightly focused, thump in your chest sound. This is strictly a matter of taste.