Planned magnetics?

Not. Today is about planarmagnetics which shouldn't be confused with ribbons.

This exploded Audeze graphic from their cookbook of planarmagnetic driver design shows symmetrical push/pull magnets on either side of the thin-film membrane with serpentine voice coil. The latter's precise geometry is one point of distinction between such drivers. Meze's Empyrean driver for example adopts a very different trace pattern. The shape of the stave magnets which must run across the diaphragm will differ as well to minimize reflections for optimized airflow. But regardless of minor variations, this is how a planarmagnetic driver looks and works. Unlike a dynamic cone or dome driven from a circular voice coil attached perpendicularly whilst being sleeved inside a magnetic gap, the planarmagnetic's voice coil covers the entire membrane to distribute the applied magnetic force far more evenly. Of course being edge clamped all around, its excursion potential is the film's innate stretch as there is no classic dynamic suspension of roll surround and pleated spider. It's why to move sufficient air, the planar's surface must scale up. This is particularly relevant outside headfi where in a classic loudspeaker, the driver sees our room, not just the miniature air volume defined by a headphone's ear cushions.

Aside from France's Diptyque and Magnepan from the US which specialize in classic dipoles, Germany's T+A and PS Audio in the US are two of the few box-speaker companies which roll their own planarmagnetic drivers not just for tweeter duty. Here we see PS Audio designer Chris show off the bigger midrange of the Aspen FR20/30 models. The one of the just-released €10K/pr FR10 is a bit smaller. Raidho and Børresen roll their own tweeter variants while Audio Physic have a unique planar/dynamic hybrid midrange. Still, planarmagnetic driver sightings in loudspeakers remain rare and PS Audio deserve a shout-out for not buying yet another off-the-shelf dynamic driver from SB Acoustics or ScanSpeak but for approaching the subject with their very own transducers whilst pursuing a very different type of driver. What do theirs sound like? Until PS Audio offer me a review sample, I haven't a blue clue. But sonic commentary wasn't why I penned today's mini feature. It was all about an uncommon tech sighting I found interesting. For once, no listening is necessary to highlight that.