The search for sustainable and biodegradable materials has been growing to replace petroleum-derived materials, commonly used by industry. Therefore, FabLabs have been investing in products produced from digital biofabrication, which is based on the concept of circular economy. At the same time, the world is undergoing a constant change and reframing of living standards, in which people seek comfort, well-being and quality to live. In this sense, leisure, work and home environments need acoustic treatments in order to minimize the impact of noise perceived by users. The objective of this paper is to present the process of defining an open source design methodology for the production of mycelium-based composites, from biofabrication using by-products and agricultural waste, with low energy consumption, aiming acoustic applications. The entire product development process was carried out at the FabLab of the Exact Sciences Campus of the Centro Universitário Newton Paiva, in Belo Horizonte, Brazil. Finally, this article concludes on the possibilities of integrating biomimicry into design, computational technology and synthetic biology for the production of efficient and environmentally friendly materials at low cost as an alternative for the market.