By Lee Min-hyung





Soongsil University professor Bae Myung-jin

Soongsil University professor Bae Myung-jin has developed new sound equipment to control decibel levels for honking of car horns to relieve potential stress of passengers and drivers.

The sound-control system, developed by a group of researchers led by Bae, can deliver a gradually growing horn sound. Bae said the idea came as the conventional pure tone horn sound is unpleasant on the ear, even though it is loud enough to instantly alert pedestrians.

"The vehicle horn system has made little progress over the past 100 years," he said. "Drivers could not control loudness levels of the traditional horns. That is why we developed the new system allowing them to send horn sounds that grow steadily without instantly delivering warning sounds over 110 decibels."

When the equipment is installed in a vehicle, it can deliver the horn sound gradually, growing from 80 to 110 decibels.

"Horn sounds can trigger road rage among drivers," he said. "By conducting brainwave reaction studies, we have proven that sound patterns with gradual changes can be less stressful than the existing horn sounds."

His research was introduced at the Acoustical Society of America last month under the title of "the friendly honk: acoustical remake of car horns alerts without jarring."

Bae teaches electronics and information engineering at the university, also serving as the head of the school's sound laboratory.

He is one of the nation's top-notch sound experts with decades of experience ever since establishing the university's sound lab in 1992. He has particularly focused on finding ways to relieve noise in people's daily lives.

In 2015, he gained global attention for developing the "sound-wind fire extinguisher." The 1.5-kilogram device can quell fires by using vibration energy from low-frequency sound and blocking oxygen inflow with a sound wind.