At Panasonic Automotive Systems, our mission is focused on how users actually feel when they are in a car, aiming to create a blissful space where everyone can feel at ease.
This time, we focus on the element of sound inside the cabin. By removing unwanted noise and tuning the sounds that reach our ears, our specialists design acoustic spaces that truly move the heart. We spoke with three of our in-car acoustic experts about the technologies behind this work and their vision for the future.
Removing unwanted sounds to build the foundation
for an acoustic space
Mr. Tani, I understand you are in charge of technologies such as Active Noise Control (ANC), which provide passengers with a quieter cabin environment.
Tani
That’s right. There are two main approaches to reducing noise inside a vehicle. One is a passive approach, which reduces vibrations and noise from sources such as the engine and road surface through the use of sound-absorbing materials and structural countermeasures. The other is an active approach, known as ANC, which reduces noise by generating sound waves from the speakers that have same amplitude and opposite phase to those detected by microphones. My main responsibility is this ANC technology.
When discussing in-car acoustics, why is reducing noise so important?
Tani
Because when people ride in a car, loud noise causes stress and leads to fatigue. It also makes it harder to hold a conversation with passengers, which adds to the stress.
Vehicle interior noise can generally be categorized into three main types: engine noise, road noise (including the road surface and driving itself), and wind noise. If you only reduce one type, the others become more noticeable—like a game of “whack-a-mole.” That’s why it’s important to look at the overall balance when reducing noise.
That said, we are not aiming for absolute silence. Some sounds—like those that convey acceleration and road contact—are essential for safe driving. If those sounds are completely eliminated, it becomes harder for the driver to sense how the vehicle behaving, which can be dangerous.
What we are aiming for is “high-quality quietness” which maintains the sounds that matter—those that support both comfort and safety— while removing the ones that can overwhelm and cause discomfort.
On the other hand, are there cases where you intentionally enhance sound?
Tani
Yes, absolutely. For example, some sports car users enjoy a powerful engine sound. With our Active Sound Control (ASC) technology, it is possible to add engine-like acceleration sounds to electric vehicle (EVs), which don’t naturally produce them. This allows us to create a sound experience tailored to fit the brand identity of each vehicle.
That said, in the future, if fully autonomous driving becomes the norm, the focus may shift toward offering a completely quiet cabin environment.
Beyond “high-quality quietness”
— creating sounds that move the heart
Mr. Asami and Mr. Otomo, your role is to refine the overall acoustics inside the vehicle, correct?
Asami
Yes, I’m in charge of the overall tuning of in-car acoustics. To be honest, a car is not the ideal environment for enjoying music. After all, it’s primarily designed for mobility, not as a space dedicated to listening. Its structure is optimized for driving performance and safety, with an emphasis on being lightweight. Even so, it is our mission to deliver the best possible acoustic experience to everyone in the vehicle.
Otomo
I’m responsible for speaker design. Speakers installed in vehicles face different constraints than home audio speakers such as durability, installation space, and cost. Installation space is a major limitation; we can’t install large speakers housed in big enclosures like home audio systems. Taking all these factors into account, my job is to design speakers that faithfully express the intentions of the tuning engineers—speakers that can reproduce music with power, stability, and clarity, without distortion. Actually, the basic structure of speakers hasn’t changed in about 100 years. At first glance, it might seem like there’s been no evolution, but within the constraints of automotive applications, the pursuit of better sound is actually incredibly deep and complex.
Exactly what kinds of innovations ensure that people can really enjoy music in a car?
Asami
As Mr. Otomo mentioned, speakers in cars are usually mounted very close to the passengers, such as in the doors or dashboard. In a proper stereo setup, you’d place two speakers at equal distance to the listener, positioned to the front. But in a car, passengers can’t sit in the exact center. As a result, you often hear more from the speaker closest to you. So, we make various adjustments to ensure that stereo sound reaches the listener naturally, no matter which seat they’re in. In principle, we first tune the system so that it performs best when the car is stationary, and then adjust it so music can still be enjoyed while driving. For example, we might deliberately boost the bass so that it doesn’t get masked by engine or road noise.
Otomo
Regarding speaker placement, with home audio, you can freely move the speakers for optimal setup, but the listening position depends on where the person chooses to sit. In contrast, in a car, the relative location between the speakers and passengers is precisely defined. This creates a unique advantage: the car allows you to reliably enjoy the soundstage we professionals have meticulously crafted. Yes, cars are challenging environments because noise can come from all directions, but in a way, that makes it even more rewarding—passengers can directly enjoy the benefits of professional tuning.
What drives you to pursue “sound,” even in such a challenging environment as the vehicle interior?
Asami
These days, enjoying music at high volume at home has become rare, unless you have a dedicated listening room. For most people, music is something they listen to through earphones or headphones. The car is one of the few places where you can enjoy music in an open space, without covering your ears. That’s why we want to create a special acoustic experience during the journey.
Otomo
I’ve always loved music, and I even compose songs as a hobby. I immediately play music when I get in the car, and many of my travel memories are tied to the songs I was listening to at the time. When I look back at an old playlist, the scenery and feelings from those trips vividly come back to me. I believe sound enriches the experience of travel. It’s the reason I’m so passionate about in-car acoustics.
The future of “Joy in Motion” through acoustics
Finally, how do you think acoustics and the “sound environment” will evolve in the mobility experiences of the future?
Asami
Once advanced autonomous driving becomes commonplace, people will be freed from the task of driving and be able to fully enjoy the mobility space. The car will gain greater value as a place for entertainment, and acoustics may evolve toward even more immersive experiences. On the technology side, we might see a future where spatial audio systems like those used in movie theaters could further advance in ways tailored specifically for cars. That could be quite interesting.
Otomo
In addition to spatial audio, another important direction is personalization—what we might call individually optimized acoustics. For example, if the driver wants to listen to one song while the passenger or rear-seat occupants prefer another, the system could adapt. Of course, there’s joy in sharing music with friends on a drive, but we may also see the option for each seat to enjoy its own music or video independently, like on airplanes.
Tani
Personalized acoustics will expand beyond music to include design of the vehicle’s own timbre, like engine sounds. For instance, when you want to enjoy driving, you might hear a tuned, satisfying acceleration sound. On the other hand, if you are focused on listening to music, the system could create a serene environment by reducing road noise and other disturbances. In short, acoustics will adapt to a wide range of needs, rather than offering a one-size-fits-all solution. We at Panasonic Automotive Systems will continue to design “Joy in Motion” through our acoustic technologies.
Mitsuhiro Tani
Joined the company in 2010 and has worked in both the Development Division and the Business Division. Since then, he has been engaged in the advanced development of acoustic control products, focusing on road noise ANC, and has been broadly responsible for everything from basic development through to mass production. His goal is to contribute to realizing low-stress mobility spaces.
What brings him comfort?
When he’s absorbed in bouldering.
Takeshi Asami
Joined Panasonic ITS in 2006 and was engaged in audio development in the Electrical Design Division until 2009. Since 2010, he has been engaged in the development of acoustic elements with a focus on acoustic tuning and system design for premium sound systems. His goal is to contribute to “Joy in Motion” by creating an environment where people can enjoy better sound while on the go.
What brings him comfort?
When reading a book over coffee at a cafe in the morning before coming to work.
Keitaro Otomo
Joined the company in 2018 and has since been engaged in the design of in-vehicle speakers in the Speaker Development Division. He is responsible for a wide range of activities, from proposals and basic design to mass production launch, for various types of speakers including standard and premium models. His goal is to contribute to “Joy in Motion” by creating inspiring mobility experiences through sound.
What brings him comfort?
When he is relaxing while listening to music.