Why a bipole (back-to-back) ribbon configuration?

A single ribbon radiates from both its front and rear faces — it is inherently a dipole. In a conventional dipole design the rear wave is typically absorbed or diffused so it does not interfere with the front. Clarisys instead mounts a second ribbon on the back of the cabinet, driven in phase with the front, creating a true bipole.

Because the two ribbons are driven in phase, they move in the same physical direction at the same instant: when both move forward toward the listener, both also push air outward — the front ribbon radiates toward the listener and the rear ribbon radiates toward the rear wall, in phase with each other. That is what makes it a bipole, as opposed to a dipole, where the two ribbons are driven out of phase and move in opposite directions, so one face pushes while the other pulls.

What this achieves

• Coherent reverberant field. The speaker radiates a coherent wavefront into the room from both faces, so the reverberant energy carries the same spectral and phase information as the direct sound. The room is energised uniformly, not from a single forward-facing point.
• Spatial realism. Because the back wave arrives at the listener after reflecting off the room boundaries, it supplies the spatial cues that a monopole simply cannot reproduce. This is the source of the "you are there" holography that ribbon systems are known for.
• Even power response. Because the two ribbons are in phase (bipole, not out-of-phase dipole), they do not cancel at the sides the way a dipole does, giving smoother total power response off-axis.
• No cabinet diffraction at the rear. The rear ribbon radiates into free air the same way the front does, so the back of the speaker is as acoustically "open" as the front.

Why only the midrange and treble

From 280 Hz upward (–6 dB crossover point), all Clarisys models — the Piccolo, Minuet, Studio, Auditorium, Aria, and Atrium — run their midrange and treble ribbons in this back-to-back true-bipole configuration. The bass section does not — it runs as a dipole, radiating from both faces of a single ribbon with the front and back out of phase. The bipole's value is spatial: it supplies directional cues and even reverberant energy in the frequencies where the ear localises direction. At bass frequencies the wavelengths are long relative to the cabinet, so a second rear-facing bass ribbon driven in phase would add little spatial information while exciting room modes unpredictably. The bipole belongs where it does something; the bass stays a dipole.