The main goal of the project is study how could the sound absorption properties of a material be improved changing the structure or shape of its surface. Additionally, more about environmentally friendly or "biocomposites" will be studied. Comparing their properties and prices with typical synthetic composites, in order to foresee their future in our market. This project is about the basic concepts of acoustics as proofing and absorption, with a specific focus on sound absorption. Morphological structures and the types of materials with better acoustic absorption will be studied, paying special attention to fiber composites. It will be giving basic notions about what composites are, what they are composed of, and the kinds that exist, especially those that are environmentally friendly, such as the composite formed by natural flax fibers and a biodegradable PLA matrix. Finally, an experimental process is executed, describing how to make a non-woven composite material, and how its surface affects its sound absorption properties.