Beryllium Acoustics

The field of high end audio speakers, both for consumers and for the professional loudspeaker markets, is developing rapidly and leading manufacturers in this area are constantly looking for materials which will improve the sensitivities, efficiencies, and overall performance of their systems while helping the environment.  Beryllium offers a unique combination of properties not found in any other common acoustic materials, and is available as domes for OEMs or as completed diaphragms for OEMs, touring sound companies, and audiophiles with compression driver systems. Click here for information on how to buy the Truextent© SSX™ precision beryllium diaphragm.

There is no doubt that of all the commercially-available materials today, Truextent pure beryllium domes yield the finest sounding compression drivers with all of the mechanical power handling capability of titanium or aluminum. Truextent beryllium domes are also found in the highest performing consumer audio applications. Why? One reason is that beryllium has the highest stiffness to density ratio of all commercial driver dome materials. This allows diaphragm assemblies to have a lower overall mass, which greatly improves the responsiveness yet still remains rigid over a wide frequency range, eliminating the “breakup” associated with the mechanical deformation of traditional domes at their resonate frequencies.

Not all beryllium domes are the same.  While there are some fake domes being sold, even pure beryllium domes can behave differently, depending on how they are made. Our Truextent beryllium dome designs use a dome formed from extremely thin sheet material (typically 25µm to 50µm thick) for superior performance.  Since it is a rolled material, it does not shatter during failure mode. Click here for more information on the differences between the failure modes of rolled material and material made through a PVD process.

We have been manufacturing beryllium domes for the acoustics industry for over 10 years. For an article from 2001 explaining a bit more of the history of beryllium in acoustics and how domes are made, click here. Please note that this is an old article and the contact information in it has changed.  This article is a reprint, with permission from Voice Coil, It is from Issue 11, September 2001, p.p. 40-44, of Voice Coil magazine. © Copyright 2001 by Audio Amateur Corporation. P.O. Box 876, Peterborough, NH 03458, USA. All rights reserved.

There have been reports of fake beryllium acoustic products being sold.  A customer of Brush Wellman - Electrofusion Products purchased a Ø1" cone and a Ø4½ cone and asked us to analyze it.  The result? The cones were titanium, painted grey to look like beryllium. For a copy of our analysis, click here (PDF format).

For a drawing of the different sizes of acoustic domes with a surround that can be made with stock tooling, click here.

For a drawing of the different sizes of acoustic domes without a surround that can be made with stock tooling, click here.

 

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For more information on using Truextent beryllium domes in acoustics, please contact Gordon Simmons, the Product Line Manager, at +1 (510) 661-9715 or send an e-mail to us at Electrofusion@BrushWellman.com.