by Neil Bauman, Ph.D.
If you are hard of hearing and are in the market for a “new” used car, here is a great resource to help you find a quiet car. Driving a car that is as quiet as possible will let you better converse without straining to hear through all the “road noise” your car makes.
While not a complete listing of all cars, the people at http://www.auto-decibel-db.com have compiled a valuable table of car noise levels at various speeds for selected cars made between 2008 and 2012.
A cool feature is that you can click on any heading and the table will sort itself by that heading. You can sort by Brand (Make), Model, Specification, Year, noise level in dB at idle, and noise level in dB at various specified speeds.
The speeds are given in metric, except for one, so for your convenience, here is the conversion between metric (kilometers per hour) and English (miles per hour).
50 km/h = 31 mph
80 km/h = 50 mph
100 km/h = 62 mph
112 km/h = 70 mph
120 km/h = 75 mph
140 km/h = 87 mph
To put things into perspective, normal speech at about 3 feet is typically around 55 to 65 decibels (dB).
You can click on any of the noise level headings at the top and the chart will rearrange itself from quietest to noisiest or vice versa by clicking the heading again.
For example, the quietest car at 31 mph (50 km/h) is the 2010 Saab 9-5 Aero at just 33.2 dB. That’s about the volume of a typical whisper. At the other end of the scale, the 2008 Dodge Viper SRT-10 is the noisiest at 31 mph, making a racket of 68.6 dB—louder than typical speech!
At freeway speeds of 70 mph (112 km/h) the quietest car is the Dodge Ram 5.7 V8 at 56.1 dB—right there at the lower end of normal speech. The noisiest car is the Chevrolet Corvette 6.2 V8 at a whopping 79.7 dB—sitting right on the upper threshold of the level considered safe for continuous listening—and sounds about 4 times louder than normal human speech. Good luck trying to have a conversation in that car!