To meet growing demands for better fuel economy, many vehicles now use a variety of techniques, including turbocharging, cylinder deactivation, and smaller engine displacement. While these techniques help automakers meet their fuel consumption targets, they change the way engines sound, yielding unfamiliar sounding drivetrains with little consumer appeal.

To enhance the appeal of their vehicles and provide a high quality acoustic experience, automakers employ a variety of techniques, including engine sound enhancement (ESE) and active noise control (ANC), to both create and suppress sounds inside the vehicle. In particular, more and more automakers are looking at ways to create or maintain their signature engine sounds. Many ESE solutions in vehicles today use mechanical techniques to amplify engine sounds. These systems are limited in their configurability and expensive to implement.

To address this challenge, QNX Software Systems offers a complete software-based ESE solution that can run on existing DSPs or processors within a vehicle's head unit, which then replays the enhanced sounds over the vehicle's loudspeaker system.

First generation ESE technology has focused on adding a small number of discrete harmonics to the native engine sound, but this approach can often sound thin and artificial. Uniquely, the QNX solution offers discrete harmonic "additive" synthesis as well as granular synthesis techniques that dynamically adapt actual engine sound recordings to the realtime conditions of the engine. Granular synthesis allows sound designers to record an existing vehicle's sound and use it as the basis of the sound in a new design. The QNX Solution also offers a rich palette of signal processing effects such as signal gains that update dynamically and filters that can map to any realtime engine data parameter.

These effects, together with the two powerful synthesis techniques, can be combined in nearly infinite ways and made audible at different points in the engine's operating range to enable rich, engaging, and dynamic engine sound experiences that until now, haven't been possible.

QNX^® Acoustics for Engine Sound Enhancement is a comprehensive solution that enables developers to create realtime synthesis of engine and drivetrain-related sounds. Compared to conventional systems that physically alter the drivetrain, the solution offers more flexibility at lower cost. System designers can integrate the library with other QNX acoustic technologies, such as active noise control, to achieve the desired soundscape inside the vehicle.

The solution includes an interactive design tool that enables developers to graphically create and audition an engine sound profile on their desktops. In a production vehicle, the sound profile is deployed with an ESE library to synchronize the synthesized sound to the vehicle's realtime data, such as RPM, for playback over the speakers.

QNX Software Systems has assembled a specialized team of acoustic engineers who provide worldwide support services for a range of development and pre-production activities. From porting the ESE solution to customer specific hardware and software environments to system audio-path verification and platform-specific acoustic tuning, the QNX team has extensive experience in automotive acoustics, meeting start-of-production schedules on time, every time.