Car noise: how can it be controlled and even transformed into something more ‘listenable’?

Car noise is generated by the engine, tires, air resistance, and more, which can be distracting and cause fatigue while driving. To reduce it, sound-absorbing materials, sound insulation, and active noise control systems are used. Electric vehicles are quieter and generate a virtual engine sound for pedestrian safety.

 

When you walk along a busy road, the noise from a large number of cars is often frowned upon. In some cases, it’s even difficult to have a conversation with the person next to you on a busy road. This noise is more than just an inconvenience, it can also cause psychological stress and adverse health effects. Studies have shown that exposure to excessively high noise levels can cause hearing loss, as well as cardiovascular disease and sleep disorders. Especially in large cities, persistent noise pollution is a significant factor in reducing people’s quality of life. As a result, noise is becoming more than just a nuisance, but a serious social and public health issue that needs to be addressed.
Noise is still an important issue when traveling in a car. Noise inside the car can irritate the occupants’ ears, causing fatigue, nervousness, and reduced concentration while driving. It can also contribute to fatigue and increase the risk of accidents, especially when driving for long periods of time. Therefore, controlling car noise is an important criterion for car comfort. Societies are also regulating noise emissions to reduce the harm caused by noise. Automakers are researching and developing various methods to control noise, and they’re introducing technology to provide consumers with a better driving experience. Let’s take a look at how we currently control car noise.
Imagine loud music playing in the corner of a room. Assuming there is nothing between the speaker and me, all the loud sounds will enter my ears and cause me pain. How can I avoid this noise? One way is to build a thick wall around the speaker. The thick wall will act as a sound barrier between the speaker and me, making the loud music sound much smaller. Next, you can try to cancel out the loud sound by creating another sound that can cancel it out. Sound is made up of different waves with different periods and shapes. That’s why we cancel them out by superimposing sounds that have the same period but opposite shapes, i.e., opposite phases. The last method is very simple and straightforward: reduce the volume of the music coming from your speakers.
The same goes for noise from a car. Car noise is usually caused by the engine running, or by friction between the tires and the road or the body and the air. If there was nothing else in the car besides the body, engine, and tires, the loud noises would get inside and interfere with your driving. To block these noises, the car is surrounded by a wall of sound-absorbing and sound-dampening materials, which absorb, reflect, or block the noise generated by the car, making it sound much smaller. Automakers are constantly improving these technologies, and more sophisticated cars, especially luxury cars, have more sophisticated sound-absorbing and sound-dampening technologies to provide a quieter and more comfortable interior.
Next, there are active noise control methods to offset the noise inside the car. This is done by installing microphones in the cabin to directly measure the noise inside the car, and then canceling it out by producing sound in the opposite phase through speakers. This is especially useful in large cars and electric vehicles, where noise can be very loud. Lastly, noise-producing components can be replaced with less noisy ones by changing their material or shape through R&D. In fact, the pattern on a tire can be changed to a different shape to reduce noise.