Kutatók laboratóriumban egy “karateşeket” készítettek, amely hangot ad

Szerző / Szerkesztő: Cem Yıldız•12 October 2026

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An engineer and his colleague have developed a “sound black hole” in the lab, which absorbs and eliminates the echoing sound in pipes. The device was tested with a 3D-printed prototype that can be attached to existing piping systems, and it was found to match computer simulations of the amount of echo returned. Sound bounces and echoes from the many sources around us and reflects off surfaces, making it extremely useful or annoying, depending on the circumstances. Sound passing through enclosed spaces in pipes, such as ventilation, air conditioning, industrial exhausts, or plumbing, can echo regularly when it encounters an obstruction or narrowing.

“The sound approaches the edge of the tube and something happens with the wave; it looks like what an outside observer would see near an astrophysical black hole: The wave takes an infinite amount of time to reach the boundary,” says Guasch. “In the ideal case, the wave doesn’t come back when it enters the tube.”

Researchers tested this with a 3D-printed prototype: the structure, which consists of 29 rings and is about 15 centimeters long, was placed on a central rod and then placed in an impedance tube, which is used to measure how sound waves behave when they encounter a material or structure. They did not shout inside the tube; instead, a speaker sent out sound waves at different frequencies, and microphones were used to measure how much of the sound returned. The results were encouraging: the amount of sound that returned from the black hole corresponded closely with the researchers’ computer simulations; however, it should be noted that the echoes did not completely disappear.

There are challenges to overcome before black hole trees are deployed on the field. Different environments bring different problems: from particles that can fill the gaps to temperature, pressure, and airflow effects. However, Guasch is excited by the possibilities of controlling sound in ways that were once thought to be almost impossible. “Personally, I’m most excited by the way physics and mathematics, which are initially quite unrelated fields of knowledge, come together,” he says. “And of course, the type of wave control that is now possible is something that only a few years ago seemed like science fiction.”