There are certain cars that you just expect to be loud. AMG Mercedes and 600 horsepower V8 Alpinas are among them, and yet, both Alpina and AMG now have no choice but to pipe fake exhaust sounds into their cabins. And you can thank a new European noise regulation for it.
“The death knell has officially sounded for noisy performance cars,” begins Australian car website Motoring’s article on how the new Mercedes-AMG A45 S and CLA 45 S are now quieter than their predecessors due to strict European regulations.
The article quotes the head of product planning for compact AMGs, Bastian Bogenschutz, who describes how new laws have forced automakers to resort to sound augmentation:
“It’s coming from the European regulations,” he explained. “We can [design specific exhausts] but it’s too expensive for every market to do it, it’s pretty difficult.”
“The regulations were getting pretty difficult for the sound to just come from the exhaust system,” he said.
“So we added the AMG pure performance sound, there we take the real sound from the exhaust system, the pulsation of the real sound and move it inside the car. It works together with the exhaust system.”
I heard similar sentiments when I spoke with representatives from BMW’s right-hand tuning partner, Alpina, in Munich back in June. Those reps told me that the B7 that I was driving in Europe had a quieter exhaust than the U.S. spec model due to new, stricter European noise regulations. A BMW representative told me that the Alpina I drove in Germany had “enhanced engine sound for the interior” coming from the speakers, and that this sound had been engineered by Alpina.
So it seems like, at least in Europe, loud sports cars are more and more becoming things of the past, and Motoring notes that using a valve with a quiet and loud setting isn’t a valid workaround, since the vehicles will apparently be tested in their loudest modes.
I will admit that I’m not sure exactly which regulation is driving these stricter exhaust requirements, but a cursory search leads me to a European Union regulatory document with an enormous title: “Regulation (EU) No 540/2014 of the European Parliament and of the Council of 16 April 2014 on the sound level of motor vehicles and of replacement silencing systems, and amending Directive 2007/46/EC and repealing Directive 70/157/EEC (Text with EEA relevance).”
This document lays out a new method for testing exhaust noise to ensure that “sound emission of a vehicle under street-driving conditions does not differ significantly from what can be expected from the [existing] type-approval test result for the specific vehicle” and also to “cover driving conditions of the vehicle in real traffic outside the type-approval driving cycle and to prevent cycle beating.”
In addition, Regulation No 540/2014 actually drops sound level limits. This, the document spells out, is all in an effort to minimize noise-related stress, potential for high blood pressure, and other health-related effects of loud automobiles.
Reg 540 specifically breaks down the obligations of the manufacturers, basically stating that they’re on the hook for making quiet cars, and ensuring that they remain quiet over time. From the document:
1. Manufacturers shall ensure that vehicles, their engine and their silencing system are designed, constructed and assembled so as to enable such vehicles, when in normal use, to comply with this Regulation, despite the vibration to which such vehicles are inherently subjected.
2. Manufacturers shall ensure that silencing systems are designed, constructed and assembled so as to be able to reasonably resist the corrosive phenomena to which they are exposed having regard to the conditions of use of vehicles, including regional climate differences.
3. The manufacturer shall be responsible to the approval authority for all aspects of the approval process and for ensuring conformity of production, whether or not the manufacturer is directly involved in all stages of the construction of a vehicle, system, component or separate technical unit.
Plus, the EU also says that it wants manufacturers to provide consumers with sound emission data:
Accordingly, manufacturers should provide information on sound levels of vehicles at the point of sale and in technical promotional material. A label, comparable to the labels used for information on CO2 emissions, fuel-consumption and tyre-noise, should inform consumers about the sound emissions of a vehicle.
Digging deeper into the paper, the regulation lays out requirements for tires used in the test (since tire noise is a significant part of the vehicle’s sound output), and states that engines should be brought to “normal operating conditions,” and that certain exhaust systems should be “conditioned” prior to measurement. Plus, the document lays out acceleration targets for the test (targets that vary based on vehicle power to mass ratios), discusses whether vehicles should be tested in two or four-wheel drive and whether electric fans should be on or off, and even gets into how gears should be selected.
Plus, it mentions specifically that cars are to be tested in their loudest settings:
Exhaust or silencing systems with multiple, manually adjustable operating modes shall meet all requirements in all operating modes. The reported sound levels shall be those resulting from the mode with the highest sound levels.
There are also some examples of how the microphones used to read the sound are to be placed relative to various types of exhaust systems:
This table at the bottom of Regulation No 540 lays out decibel requirements based on power to mass ratios (a separate table exists for vehicles meant for “Carriage of goods”):
As shown, things get stricter over time, with 2020 and 2024 apparently being the key dates for the initiation of stricter noise limit phases.
Is any of this this terrible of a thing? To sports car diehards, yes—fake exhaust noise isn’t cool. That said, exhaust noise is mostly there for cabin occupants to enjoy, and not to impress folks outside of the vehicles. So, in a way, exhaust/augmented engine noise is logical, especially in the dense cities of Europe.
That said, I myself enjoy living in a place where car fans can straight-pipe their compact beaters to make them louder than Lamborghinis. But that’s just me.