Somewhere between thick and opaque noise-blocking curtains and clear sound-reflecting glass windows there was a missing link, and this textile is it: lightweight and translucent, it sucks in sound without obscuring your view. Though it sounds like a bad translation, when the designers say this design “quenches” sound, they’re using that word deliberately.
Specializing in Materials Science & Technology, the EMPA worked with textiles experts, acoustical engineers and computer modelers to weave disparate disciplines into a new compelling set of acoustically-altered patterns. Passive noise cancellation is of course a particularly tricky task in malleable and thin materials due to issues of density and directionality.
Mathematical projects and digital models led to real manufacturing and testing, resulting in something five times more soundproof than traditional hanging curtains (and significantly better than bare concrete or glazed surfaces) but still sufficiently fireproof and translucent to let in strands of daylight. Insert additional thread-and-weaving-related jokes here.
“Acousticians are pretty astonished when they see the readings we are achieving with the new curtains in the reverberation room,” says Kurt Eggenschwiler, head of EMPA’s Acoustics/Noise Control Division. “The weighted sound absorption coefficient is between 0.5 and 0.6. In other words, the new textiles ‘quench’ five times more sound than conventional translucent curtains. The new curtain genuinely absorbs sound, noticeably improving the room acoustics – and its design is also very high quality.”
Read on for more technical information about how these curtains were designed.
|“The first acoustically optimized lightweight textile came into being on a computer. The Empa acousticians wanted to use the characteristics of this virtual textile in order to prepare a kind of «recipe» for material experts, which would enable them to specifically manufacture a fabric that could absorb sound. In addition, they first developed a mathematical model to illustrate both the microscopic structure of the fabric as well as its macroscopic composition.”
“On the basis of numerous acoustic measurements made on various samples, specifically woven by Weisbrod-Zürrer, they were able to gradually optimise the acoustic properties of the fabric. Annette Douglas then succeeded in translating the new findings into weaving techniques. She chose yarns that gave the materials the necessary characteristics in terms of flammability and translucence and determined the weave structure, i.e. how the threads should be woven in and out of each other. Weisbrod-Zürrer then adjusted the sophisticated manufacturing process so that the industrially-made curtains actually displayed the required acoustic characteristics.”