Why Do Modern, Fuel-Efficient Car Engines Still Make So Much Noise?

Your car or truck may be keeping a secret from you. Perhaps you fell in love with the throaty roar of your new Mustang’s engine, that rumble-rumble-rumble associated with yesterday’s gas-guzzling V8s, but it’s probably just an illusion. Automakers across the spectrum, from BMW and Volkswagen to Ford and even Toyota with its soft-spoken Prius, are piping enhanced engine noises into car interiors. The theory is that potential consumers equate quiet engines with less powerful vehicles, thus costing the manufacturers valuable sales. The quiet, modern engines provide drivers with the fuel economy they want, while the fake or amplified engine sounds nostalgically emulate the growl of a more classic but less fuel-efficient car.

Listen to that engine purr:

• Ford’s Active Noise Control system in Mustangs and trucks amplifies the engine’s purr through the car speakers, making the vehicles seem “athletic and youthful.”
• Volkswagen uses what it calls “Soundaktor,” a special speaker system that reproduces engine noise in cars such as the Golf, Jetta, and Beetle Turbo. Even the V10 sounds of the Lexus LFA supercar are boosted with electronics developed by Yamaha.
• Adding noise makes sense for electric cars, which run so quietly that you often don’t hear them coming. Regulators are expected to require safety noise enhancements on all hybrid and electric cars.