When riding in a car at highway speeds, there are several sources of noise that need to be tamed in order to have a truly quiet cabin. The main sources include engine noise, tire noise and wind noise, all of which can be reduced with proper engineering. Engine noise can be quieted with a different exhaust system and softer engine mounts, tire noise can be reduced by using less aggressive tires, and wind noise can be silenced by using various aerodynamic tweaks. Additionally, acoustic glass and sound deadening can be installed to further reduce any leftover noise. Read on to find out which models have made our list of the 10 quietest cars, based on low NVH (noise, vibration and harshness) levels.
10 of the Quietest Cars
Photo Credit: Audi
The Audi A8 is one of the quietest cars you can buy, based on low NVH levels. The smooth engines can get loud and emit a sporty roar when you put your foot down, but the rest of the time, the A8 is very sedate, with dual-pane acoustic glass and plenty of sound deadening to help eliminate road and wind noise. The interior is superb, and the relative silence means that you can enjoy every note that emanates from the 14-speaker Bose surround system (or the optional 19-speaker Bang & Olufsen surround-sound system). The combination of the peaceful and luxurious interior makes the Audi an excellent car to spend some time in.
Photo Credit: Mercedes-Benz
The S550e is a plug-in hybrid version of Mercedes-Benz’s top-of-the-range sedan. While it obviously gets better fuel economy than the standard version, another benefit is that the internal combustion engine usually doesn’t have to work as hard, with the quiet electric motors helping out when possible. There are some of the typical hybrid downsides, including a smaller trunk and a higher curb weight due to the additional batteries, and when driving aggressively, the normal S550’s big V8 can be quieter than the S550e’s V6, but in most situations, the hybrid provides a very quiet and smooth ride, making this one of the quietest cars based on its NVH levels.
Photo Credit: Tesla
Tesla Model S
The Tesla Model S is a fully electric car, which helps make it one of the 10 quietest cars on the market, though it isn’t quite as quiet as you might expect once you get up to speed. At a stop the Tesla is nearly silent, and around town the electric motors are very smooth and barely noticeable. Once up to speed, the road and wind noise become the most prevalent noises (due to the lack of noise from an internal combustion engine), and while they aren’t quite as well isolated as they could be, the Tesla is still very comfortable.
Photo Credit: Hyundai
You usually expect compact cars to be rough and noisy, but the Hyundai Elantra is surprisingly quiet, with low NVH levels. The latest generation uses a variety of tricks to keep sound levels low, including more high-strength steel, a subframe-mounted front suspension, more sound deadening, and thicker glass. The suspension rides almost like a German sedan, but without the nimble and exciting handling you’d normally associate with a firm ride. Entry-level models get a good array of standard features, and other than the interior materials, higher end models of the Elantra feel like they could almost be luxury sedans.
Photo Credit: Lexus
The Lexus GS is a rear-wheel drive midsize luxury car with some sporty pretensions, particularly in F Sport trim. Like most cars from the brand, the GS is very quiet in most situations, especially on the highway; if driven aggressively, the GS makes a decent exhaust noise, but one that is never intrusive, making this one of the 10 quietest cars available. The ride is a good trade-off between handling and comfort, even in the sportier trims, and the seats are comfortable. The Remote Touch Interface isn’t one of the better in-car control systems but it is workable, at least once you get a hang of the system.
Photo Credit: Kia
While the Kia Optima’s base normally-aspirated engine isn’t as smooth or powerful as the optional turbocharged units, it is quiet, at least until you mat the accelerator looking for some power. The other engines are nearly as quiet, and are willing to provide the Optima with much more motivation. For the more frugally minded, a hybrid model is also available. To keep road and wind noise out, the Optima uses acoustic laminated glass and more sound insulation, and the result is a car nearly as quiet as the best luxury sedans, and one that makes our list of the 10 quietest cars available today based on low NVH levels.
Photo Credit: General Motors
The Cadillac CT6 is a very attractive fullsize luxury car that hopes to do battle with the best Germany has to offer, as well as taking a spot on the list of the 10 quietest cars. The interior is soothingly quiet and the ride is comfortable, though at lower speeds the drivetrain can sometimes feel a bit rough around the edges. An optional Bose Panaray sound system takes full advantage of the near-silence with a grand total of 34 speakers (more than found in all the cars on some dealer’s lots only a few years ago). The CT6 isn’t exactly sporty but it is willing enough in most situations, especially in rear-wheel drive trim with the smaller (and lighter) turbocharged 4-cylinder engine.
Photo Credit: Audi
The A6 is the second Audi with low NVH levels to appear on this list, and while it isn’t as quiet as its bigger brother, it does come close. Road noise is probably the most predominant interior noise, but it isn’t intrusive. The engines are smooth and pair well with the transmissions, no matter what your driving style. The interior looks and feels very high quality, with a simple yet classy design and real wood inlays. The A6 handles well until pushed to the limit (where the typical Audi understeer makes itself known), though the ride might be a bit stiff for some, so think twice before blindly adding sporty features and bigger wheels.
Photo Credit: Kia
The Kia K900 is an affordable fullsize luxury car that does a good job of matching its competitors' features. While some aspects of the K900 (such as the interior plastics) might be a step behind other offerings in the segment, it also comes at a much lower price. Unlike other vehicles in the class that manage to blend both comfort and handling, the Kia isn’t eager to race around corners. On the other hand, it is comfortable, and thanks to features that include laminated windows and underbody trays (which also help to improve aerodynamics), the K900 is one of the 10 quietest vehicles with low NVH levels.
Photo Credit: Toyota
The Toyota Prius is a midsize hybrid car that achieves excellent fuel economy while at the same time providing a quiet ride, thanks to the judicious use of both its electric and gasoline powerplants. Also helping to keep noise levels down are an increase in the amount of sound deadening and a significant increase in the amount of high-strength steel used in the car’s construction. The latest generation of the Prius is more economical and more comfortable, while also featuring more power and better handling. If Toyota can maintain the pace of their improvements, the Prius will soon be hard to compete against.