Graphene in loudspeaker membranes

Research Project, 2017 – 2018

An ideal speaker membrane would be stiff and capable of efficiently dissipating the exceeding heat of the speaker. Currently it is not the case, limiting the performance of speakers even at the high-end. A cellulose-graphene composite, by capitalizing on the intrinsic properties of the materials would ideally offer the right technology. To demonstrate this, we plan to use a commercial paper loudspeaker membrane modified with the composite. This way we can modify any size of paper cones from small 20 mm (tweeters) up to 460 mm (18” woofers) with the same technology, while offering the possibility of decreasing the distortion.

As paper membrane loudspeakers are still used in most audio systems around the World, we hope to improve the performance by a factor 10. Only starting with the high-end sector would demonstrate the concept for further generalization.

The project will engage three main partners. Transient Design Sweden will provide the expertise on sound-related technology and on loudspeaker benchmarking. Chalmers Industriteknik will provide general know-how on graphene, and will in investigate IP issues as well as other commercial and dissemination aspects. Applied Chemistry at Chalmers will support the project with expertise on formulation, especially cellulose based.

The proof of concept will be done by coating a membrane with a formulation of the graphene mix. The effect of the coating will be assessed in terms of reduction of distortion, among other criterion. Effects such as coating thickness and density will be evaluated.