news 2019

A team of Empa acoustic researchers has built macroscopic crystal structures that use internal rotation to attenuate the propagation of waves. The method makes it possible to build very light and stiff materials that can also "swallow" low frequencies very well, as they report Communicatons. The world of crystals offers many interesting properties: crystals can strike electric sparks in disposable lighters, for example, they can produce polarized light and they can scatter bundled X-rays into thousands of individual reflexes that are refracted in all spatial directions.

To play a piece of music as it was conceived by the composer is a trend. But where can the rare historical instruments be found? The solution would be exact copies of the coveted originals. A team of Empa researchers is analysing such replicas with the aim of reproducing historical trombones with their typical sound.

A rippling stream is Jean-Marc Wunderli's favourite sound. However, his everyday research has little to do with calming natural sounds. He deals with completely different ones: noise from aircraft turbines, train noise, busy roads, wind turbines and now even drones. All these emissions are part of the research activities of Empa's Acoustics / Noise Control Lab, which Wunderli is heading since last July.

A new study by an international team headed by the University of Zurich sheds light on whether animal vocalizations, like human words, are constructed from smaller building blocks. By analyzing calls of the Australian chestnut-crowned babbler, the researchers have for the first time identified the meaning-generating building blocks of a non-human communication system.

Researchers at UNIGE and at Maastricht University have demonstrated that the brain adapts to a person's listening intentions by focusing either on a speaker's voice or on the speech sounds that are being uttered.

What makes Beethoven sound like Beethoven? EPFL researchers have completed a first analysis of Beethoven's writing style, applying statistical techniques to unlock recurring patterns. EPFL researchers are investigating Beethoven's composition style and they are using statistical techniques to quantify and explore the patterns that characterize musical structures in the Western classical tradition.

Diet-induced changes in the human bite resulted in new sounds such as "f" in languages all over the world, a study by an international team led by researchers at the University of Zurich has shown. The findings contradict the theory that the range of human sounds has remained fixed throughout human history.

Railway noise is annoying. Trains cause numerous sleepless nights, especially in the vicinity of residential areas. This makes it all the more important to optimize trains and tracks in such a way as to dampen sounds. Empa researchers have devised a computer simulation that demonstrates how railway noise is created in the first place and which technical measures are effective in preventing it.