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Materion’s Truextent premium acoustic beryllium is used to make domes, cones and diaphragm assemblies for high-end loudspeakers and headphones. Recognized around the world by OEMs and ODMs, Truextent genuine beryllium creates superior acoustic parts for crystal-clear sound reproduction. 

Using beryllium for acoustic components eliminates audible ringing and distortion heard from traditional materials like titanium or aluminum. In high frequency drivers, our advanced acoustic parts are capable of reproducing sound beyond an extra octave of useable, non-resonant high-frequency energy. The speed of sound in Truextent speaker domes travels 2.5 times faster than it does in aluminum or titanium domes, pushing breakup modes 2.5 times higher in frequency. 

We produce speaker domes with and without surround assemblies from our library of standard geometries. Our material forms include custom fabricated speaker domes, custom speaker cones and domes for headphones and in-ear monitors, and BeX diaphragms for loudspeakers. These products are available in a range of sizes suited for tweeters, HiFi midrange, woofers, compression drivers and high-end headphones.


We use a unique method to produce Truextent material. Beryllium metal is rolled under extreme heat and pressure numerous times into a thin foil. This process creates a highly uniform grain structure, unlike physical vapor deposition (PVD), a process used by other companies that make acoustic beryllium. Rolled beryllium foil has increased durability when compared to PVD.

Watch the video below of a laser scan of a Truextent beryllium dome compared to scans of aluminum and titanium domes.

See a technical comparison of Truextent beryllium with traditional materials.

ADVANTAGES OF TRUEXTENT DOMES AND CONES | Increased durability of the grain structure | Fewer mechanical deformations under stress | Higher damping for distortion-free sound | Extra usable octave of resonance free high frequency sound | Greater responsiveness due to low mass

We used tuning forks to create a measurable comparison of beryllium to traditional audio materials. See the results.


Our Truextent® genuine beryllium BeX4008/4016 precision replacement diaphragms combine premiere materials with precision manufacturing to provide exceptional power handling, high sensitivity and significantly improved clarity of sound with extended bandwidth over that of factory originals. BeX diaphragm assemblies are engineered to fit a variety of large format compression drivers.

All Truextent BeX diaphragms are designed with aluminum wire edgewound voice coils, hot-formed Truextent genuine beryllium domes and PEEK polymer surrounds. They are available in 8Ω and 16Ω impedances and the BeX4000 series fits a variety of JBL and Radian compression drivers.

For additional properties, view our BeX compression driver diaphragm assemblies product brief.

To see the advantages of BeX in a Radian compression driver, download our technical analysis

There is no other material like beryllium for loudspeakers and headphones. Beryllium’s unique combination of high stiffness, low mass, and high damping enhances speakers and enables the highest definition audio and crystal-clear sound.

For more information about our Truextent genuine beryllium BeX diaphragm or our Truextent acoustic beryllium foil, talk with our engineers.