The goal of this thesis was to create a functional 3D printed speaker enclosure and to determine how its acoustic properties are affected by the use of different materials. For this purpose three identically shaped enclosures from three different thermoplastics were created and their frequency responses and harmonic distortions weremeasured.
In theoretical part, 3D printing is presented with special emphasis on describing the technologies based on material extrusion, namely the extrusion of thermoplastics, which we have used to print the enclosures. This is followed by a brief presentation of 3D-modeling and presentations of electrodynamic loudspeakers and speaker enclosures. When preparing the latter we have discovered that spherical enclosures have the best acoustic properties, which we have taken into account when creating the design. While examining the state of present research, we have presented and described interesting speakers with 3D printed enclosures.
The experimental part contains a description of the design and modeling processes of an elyptical enclosure as well as printing of the enclosure with three different thermoplastic materials or filamentsbased on ABS, PLA, and a composite filament of PLA and wood fibres. Two desktop printers were used, namely CubePro Duo and Witbox. Same settings for all three prints were used. The best results were achieved when printing with PLA filament on CubePro Duo whilethosewith wood filament on Witbox were the worst. The speaker was first fixed onto a wooden ring and this assembly was then temporarily attached to each enclosure to study its acoustic properties. The measurementswere conducted in an anechoic chamber of the Faculty of Electrical Engineering in Ljubljana using professional equipment. Our frequency responses differedby approximately ±5 dB from those stated by manufacturer. Harmonic distortions were below the level of perception. No relevant acoustic differences between the three enclosures were found.
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