Printed on the tip

Text: Frank Roessler / Pictures: Audio Physic — April 5th 2019

3D printing eliminates vibration at the point of its creation - in a high-end speaker

For over 30 years Audio Physic from Brilon in the Sauerland region of Germany has been committed to building loudspeakers that meet the highest standards and in which everything is geared towards pure, unadulterated sound. Everything, right down to the materials, is pushed to the extreme.

The HHCM-III midrange driver in Audio Physic's Structure high-end loudspeaker is based on two nested baskets. These are designed to decouple the vibrations of the diaphragm from the cabinet. To improve this decoupling, developer Manfred Diestertich employs on additive manufacturing.

The midrange driver was designed as part of a research project to determine what can be achieved with 3D pressure in loudspeaker construction. The double basket is made of polyamide added with different filling materials (hollow glass spheres, aluminium additives). The printed structure should have properties similar to those of a foam in order to dampen vibrations optimally even in the material. According to Diestertich, the nested structure could not be reproduced using conventional production methods for loudspeaker baskets (casting, milling, punching).

Design and production

Diestertich had the idea to fight vibrations in a new way within the filigree basket structure. The first digital drafts were converted into realizable print files in close cooperation with a service provider for additive production. In several steps, a feasible product was approached.

The cost of the additive components is considerably higher than that of conventionally produced chassis baskets: The baskets cost about € 700 per chassis - a conventionally produced basket is in the lower two-digit range, depending on the number of units produced, even for higher quality loudspeakers. However, the higher manufacturing costs due to the 3D printing according to Diestertich are not significant in view of the price per pair of the Structure loudspeaker, which can amount up to € 50,000 depending on the enclosure materials, and the complex design of the enclosure.

Sound result justifies more effort

Manfred Diestertich's summary of the use of 3D manufacturing technologies is extremely positive: »Although the design and implementation effort was considerably higher than with a conventional design approach, the sound result and the quality of the finished product easily justify it.« Initial reactions to the loudspeaker and its sound were very positive, and according to Diestertich, the inherent sound of the cabinet and its vibrations could also be excluded as far as possible.

The demanding clientele of high-end audio fans is very interested in the new production approach. Currently, Audio Physic with its 3D-printed components also has a unique selling point in the scene, with which the Sauerland company can set itself apart from the competition, as the company says. Diestertich is already planning to use the additive production in future projects, possibly on an even larger scale.