The Slatefiber membrane

Aesthetics and performance

After more than four years of Research & Development, Focal unveils in 2019 a new technology with remarkable performance: the Slatefiber membrane.

Made in France, this membrane is characterized by a dynamic, rich and very balanced sound, particularly in the midrange. With its acoustic qualities and unique " slate effect ", it is becoming a high-fidelity benchmark in its price category.

An authentic composite membrane

The Slatefiber membrane is a composite cone made from non-woven recycled carbon fiber - Focal is the first audio brand to use recycled carbon fiber in its loudspeakers - and thermoplastic polymer. The combination of these two materials delivers excellent acoustic performance in terms of sound velocity, rigidity and damping.


Carbon fibers alone are exceptionally rigid. What's more, the fibers are all oriented in the same direction, making the loudspeaker even stiffer, for even more bass.


The carbon fibers are oriented, but also non-woven to ensure better damping. The thermoplastic polymer is located at the heart of the fibers to ensure the bond between them and thus increase damping.


During development, particular attention was paid to the weight of the diaphragms in order to optimize sensitivity: carbon fibers are very light, so in addition to rigidity and damping, this diaphragm meets the criteria of lightweight loudspeakers.

Made in France

Like the Flax, K2 and W membranes, the Slatefiber membrane is entirely manufactured in Focal's Focal workshops in Saint-Etienne, France..

In order to combine productivity, performance and French manufacturing, Focal engineers have developed a semi-automated industrial tool dedicated to the manufacture of the Slatefiber membrane.

Focal products using this technology


Subscribe to our newsletter and receive a preview of the latest audio innovations from Focal and Naim.