Playing ukulele in the key of 3D

By Richard A Lovett

Some musicians are traditionalists, while others love to experiment with new instruments. If in doubt, consider the effect of the electric guitar and the synthesiser on popular music.

The next wave of new instruments might, however, be something entirely different from anything seen before: high-tech replacements for conventional instruments that, instead of being laboriously constructed by hand, are created by the combination of computer-aided design and 3D printers.

Could this process someday replicate the sound of a Stradivarius violin? Nobody knows. Creating such instruments is a new process, says Xiaouy Niu, an undergraduate researcher at the University of the Chinese Academy of Sciences, Beijing.

In a first attempt to test the sound quality of such instruments, he says, his group created the world’s first 3D-printed ukulele and compared it to a standard wooden instrument.

To test it, they used a simple mechanical device designed to pluck the strings of each instrument with equal force.

From this, they discovered that the printed version did not produce as much sound volume as the traditional wooden one.

They also discovered that the traditional instrument was richer in high-frequency overtones than the printed one, thereby producing a different musical timbre.{%recommended 1458%}

To explain the differences, Niu explained at this week’s meeting of the Acoustical Society of America, his team carried out computer calculations to model the ukulele shape and determine its acoustical properties. 

In the future, Niu says, such modelling efforts may make it possible to create a printed instrument whose shape and materials have been designed to produce sound that matches that of traditional instrument at a fraction of the cost.

But for the moment that’s pie in the sky, especially for a first-of-its-kind undergraduate research project operating under tight time constraints. 

Instead, the instrument tested by Niu’s group was created from a standard plastic known as polylactic acid, or PLA, which is popular for producing 3D-printed objects because the printing can be done at low temperatures. 

“Maybe in the future, if I have the money and time, I would research different materials’ acoustic qualities,” he says.

Furthermore, he says, his team has yet to look at how to shape printed instrument bodies to produce the best sound – as opposed to just replicating the shape of traditional ones.