On the sound of a large 3D-printed and assembled musical instrument: The case of the yi?aki

Nowadays 3D printing technology has allowed humanities scholars and cultural materials conservators to create replicas of indigenous musical instruments, with which they can perform various studies. However, the size of the 3D printed objects are limited by the size and the range of movements of the 3D printer. Hence, large musical instruments have to be fabricated in parts and then carefully assembled prior to playing. Here we investigate the yi?aki, a large pipe-like indigenous Australian wind instrument that is played by vibrating the lips while breathing circularly on the mouthpiece. Traditionally, a yi?aki is made from the trunk of hardwoods hollowed by termites. We scanned the internal and external shape of a traditionally-made yi?aki, built a digital model from the scanning data, printed the model in several parts, and assembled the parts into a replica yi?aki. This replica was printed using sintered nylon and assembled using a two-part epoxy. Both the original and the replica yi?akis have been played by musicians and the resulting sound data have been analysed. Our results show that, even though the replica generates yi?aki-like sounds as expected, there are subtle differences between the sound of the original and the replica.