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Engine sound quality is a key attribute for sporty cars - it powerfully conveys the brand image to the driver/passengers and onlookers, and provides driver involvement by giving instant feedback about how a car is operating. Providing this has become more difficult with tighter pass-by noise regulations and the near-universal adoption of turbocharging. In the last two decades, sporty sound inside the cabin has been regained using intake sound generator systems that transfer sound more directly to the vehicle interior. The high cost of these systems is more recently driving a move towards electronic Active Sound Design with systems delivering synthetic sound through loudspeakers. However, the purist sports car market perceives this approach to be fake or artificial. An alternative approach is provided by a system for Realistic Augmented Sound by Ricardo (RAS-R) that offers a choice of two realistic engine sound sources.

A new pass-by noise test method has been introduced, in which engine speeds and loads are reduced (compared to the old test method) to better reflect real world driving behavior. New noise limits apply from 1 July 2016, and tighten by up to 4dB by 2026. The new test method is recognized internationally, and it is anticipated that the limits will also be adopted in most territories around the world. To achieve these tough new pass-by noise requirements, vehicle manufacturers need to address several important aspects of their products. Vehicle performance is critical to the test method, and is controlled by the full load engine torque curve, speed of response to accelerator pedal input, transmission type, overall gear ratios, tire rolling radius, and resistance due to friction and aerodynamic drag. Noise sources (exhaust, intake, powertrain, driveline, tires) and vehicle noise insulation are critical to the noise level radiated to the far-field.