What are Planar Magnetic Drivers?

Planar Magnetic Driver
Exploded view of a planar magnetic driver

Structure of a Planar Magnetic Driver
The basic structure of a planar magnetic driver consists of a frame which contains a magnetic array, of which on top of it sits a planar membrane with a coil fabricated on its surface. When an electrical audio signal is fed into the driver coil, an electromagnetic field is generated which interacts with the existing permanent magnetic field what is set up by the magnetic array. This causes the planar membrane to vibrate and then produce sound.

How do Planar Magnetic Drivers sound?
Most earphones and In-Ear Monitors (IEMs) today utilize dynamic and/or armature drivers. While they have their merits, the biggest drawback is that dynamic and armature drivers focus vibration in a small area of the driver in order to produce sound. This is the speaker cone in dynamic drivers and the metal armature in armature drivers. Whereas in Planar magnetic drivers, the vibration is spread out across the entire membrane and the entire membrane moves. This produces sound with a more “planar” characteristic as opposed to sound coming from point source. This makes planar magnetic drivers sound more spacious and layered instead of sound coming from within your head like those produced by common dynamic and armature drivers.

Why aren’t there many Planar Magnetic IEMS or Earphones? 
Tradationally, planar magnetic drivers are large and are found only in big headphones, and there are numerous challenges associated with miniaturizing such drivers to fit into an IEM while still having a true sound. The biggest challenge is that when the size of the driver is simply reduced, the space for magnets and the coil decreases significantly, leading to a dramatic reduction in driving efficiency. However, Stage’s unique approach and patent pending technology overcomes this problem and maintains efficiency whilst still producing sound true to its full sized counterparts.

We will talk more about the technology power stage in future posts. Stay tuned!