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HARMAN has recently announced that a major European-based automaker will be integrating our exclusive HALOsonic™ External Sound Synthesis (ESS) solution in a new line of plug-in hybrid vehicles. The HARMAN HALOsonic ESS solution is a potentially life-saving technology that generates sound outside the vehicle, particularly targeted at hybrid or electric vehicles that are virtually silent at low speeds.  The HARMAN system offers benefits to both drivers and nearby pedestrians.

Due to their unusually quiet drive systems, electric and hybrid vehicles don’t provide the same audible feedback as conventional vehicles.  Drivers lack the familiar engine sounds that keep them aware of speed, and pedestrians may be unaware that a vehicle is approaching.   Working in collaboration with automotive legend Lotus Engineering, HARMAN has developed the exclusive HALOsonic™ sound management solution to equip electric vehicles with audible feedback both inside and outside the car.  


HALOsonic™ technology offers a technically sophisticated,solution for every acoustic challenge and is available to car manufacturers throughout the world - either as an integral part of the infotainment system or as an independent unit integrated in the existing sound system.   The innovative technology is composed of separate acoustic solutions to improve safety both inside and outside the vehicle.

Electronic Sound Synthesis (ESS)

External:  A specified electronic sound is applied to an external speaker system to improve pedestrian safety. The synthesized sound, dependent on speed and direction, is projected from speakers at the front and rear of the vehicle, giving an early warning to pedestrians that the car is approaching. The sound is projected only in the direction of travel, fading away almost instantly once the vehicle has passed. A synthetic engine ‘idle’ sound is also produced when the vehicle is switched on and the handbrake is released .

Internal:  HALOSonic technology also allows sound contouring inside the cabin, enhancing the driving experience by creating speed and throttle-dependent sounds available through the in-car entertainment system. The system delivers audible feedback to drivers even when the engine is almost silent. The creation of internal sounds is independent of exterior noise levels .

Engine Order and Road Noise Cancellation (EOC and RNC)

Both noise cancelation technologies and interior engine sound can be integrated into the existing audio system within the car, with the addition of between 4 an 8 microphones for EOC and between 4 and 8 accelerometers for RNC, strategically positioned close to the suspension.   Exterior engine sound synthesis features an additional speaker assembly at the front with an optional one at the rear for improved reverse travel warning.  They can be single solutions or can be combined -- either embedded within a HARMAN audio system or as stand-alone hardware integrated within the existing vehicle entertainment system. 

Engine Order Cancellation (EOC):  The noise produced by combustion engine activity and exhaust is substantial. Traditional methods for reducing the transfer of this noise to the cabin have involved using large amounts of NVH material. All of this sound deadening material is heavy, adding weight to the vehicle which transfers to higher CO2 emissions and poorer performance. HALOsonic™ EOC technology use a series of Error Microphones in the cabin which identify the frequencies of noise created. These are relayed to the processor which generates a cancelling frequency played back through the audio system, reducing the noise heard by the occupants.

Road Noise Cancellation (RNC):  Multi link suspensions create multiple noise paths into the vehicle.  Combined with the current trend for wider, low profile tires, road noise emanates through the structure of the vehicle, creating a “droning” noise which may increase driver fatigue.   The HALOSonic system utilizes a series of microphones in the cabin to identify the frequencies of noise created, relaying them to a central processsor which generates a canceling frequency played back through the audio system.  Much like the noise-cancelling headphones used with many portable audio systems, this technique eliminates most unwanted sounds to improve the overall driving experience while enhancing the performance of in-car entertainment systems.

Combined with other HARMAN innovations for hands-free, eyes-free infotainment, these new technologies ensure the safest, most enjoyable driving experience available to motorists today.  Contact your favorite automotive dealer or manufacturer to learn which vehicles feature our next-generation systems.

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