Hyundai develops 'nearly silent' cabin

The sound of near silence inside vehicles will soon become reality thanks to a newly-patented noise-cancelling technology that promises to set new standards in noise, vibration and harshness (NVH) reduction.

The claim comes not from Mercedes-Benz or BMW but Korean car-maker Hyundai, which says its research and development arm has created a 'nearly silent' cabin environment via what it calls Road Noise Active Noise Control (RANC).

Hyundai reckons RANC can reduce intrusive cabin noises by 3dB and the world-first technology will be deployed on Hyundai's luxury brand Genesis first, potentially in its upcoming SUV.

After six years of development with the Korea Advanced Institute of Science and Technology and testing the tech with audio company Harman, the new system targets road noise in particular and can isolate acoustics for the driver and both front and rear passengers independently.

"RANC is a remarkable technology which takes existing NVH technology to the next level," said Gangdeok Lee, a Research Fellow of NVH Research Lab.

"We will continue to take the leading position of NVH technology and deliver the highest level of quietness to customers," added Lee.

Noise reduction measures in cars aren’t new, with passive sound-damping foam materials having been in use for decades to quell road and engine noise.

It is not the first time noise-cancelling technology has been used in vehicles either, with active sound cancelling tech employing microphones to detect cabin frequencies and then play back counter-frequencies to nullify certain acoustics – in the same way that noise-cancelling headphones work.

But Hyundai says RANC takes the tech further by analysing "various types of noise in real-time" then pumping out inverted sound waves in a more detailed, targeted manner, to quash resonant sounds such as tyre noise and rumbles emanating from the road.

How does it work? We'll let Hyundai explain:

"Using an acceleration sensor, RANC calculates the vibration from the road to the car and the control computer analyses road noise. As its computation and signal transfer speeds are optimised, it only takes 0.002 second to analyse the noise and produce an inverted sound wave, generated by the DSP (Digital Signal Processor).

"The microphone constantly monitors the road noise cancelation status, and sends the information to the DSP. RANC is able to conduct accurate noise analysis and rapid computation to combat road noise for the driver’s seat, the passenger seat and rear seats separately."

Clear as mud?

According to Hyundai, the new technology will reduce the amount of sound deadening and insulating materials required in car, thereby reducing unsprung weight and improving performance and fuel efficiency.

The Hyundai Motor Group has now filed patents in Korea and the USA for the RANC technology, specifically related to signal selection methods and the location of sensors.

The end-game for Hyundai is to get a jump on its rivals when it comes to EVs and FCEVs, in which road noise will be the main source of acoustic interference given that electric motors are much quieter than combustion engines.

"Utilising RANC can significantly reduce road noise and create a serene cabin for future electric and [hydrogen] fuel-cell electric vehicles," says Hyundai.