Although Audi's future e-tron models will be powered by practically silent electric motors, the vehicles will still emit sounds, albeit electronically. According to Audi engineer Rudolf Halbmeir, sound is an “exciting aspect” of a vehicle that plays a crucial role in driving experience. Thus, he is developing Audi e-sound for all future e-tron models.
All models will have a synthetic sound signature, distinct from one another. The e-sound will allow drivers to experience real driving. According to the company, sounds send signals to the driver and passengers: low-range frequencies suggest power and composure while mid-range frequencies emit sportiness and agility. Using this as reference, Audi’s e-tron sports car models in the future will emit e-sounds of mid-range frequencies, to register an aura of sportiness and agility.
According to Dr. Ralf Kunkel, Head of Acoustics at Audi, their experience on auto acoustics enabled them to gain expertise, allowing them to learn how to amplify pleasant frequencies and to suppress unpleasant noises. With this, Audi aims to build vehicles that produce sound signatures that are not only well-rounded and harmonious but also give a sense of premium quality and respectability. But making distinct sound signatures for each model is not easy as Kunkel admits that good sound design is a complex endeavour.
Halbmeir conducted a demonstration how e-sound works. He drove a red Audi R8 e-tron, making different gas pedal movements as he negotiates the road. As it is, the car indeed sounds like a sports car. The R8 e-tron will be just the beginning for Audi, as Halbmeir continues to develop and search for the right acoustic signature that would fit a certain e-tron model.
The Audi R8 e-tron proves how expressive and lively electric mobility can be. It has two electric motors that are supplied by a 48.6 kWh battery that can reach 280 kW (380 hp) with 820 Nm (604.80 lb-ft) of torque. This is so that the high-performance sports car can go from 0 to 100 km/h (62.14 mph) in 4.2 seconds and on to a governed top speed of 200 km/h (124.27 mph). The battery keeps its charge for a range of 215 kilometres (133.59 miles). With the R8 e-tron, Audi has honed its expertise to the benefit of all its electric models.
Weighing 1,780 kilograms (3,924.23 lb), the Audi R8’s body, including the sides, weighs only 199 kilograms (438.72 lb), 23 kilograms (50.71 lb) less than the R8 Coupé, which itself set a very high bar with its aluminium ASF principle (Audi Space Frame). Audi introduces a new development stage in its ultra-lightweight construction technology - a Multimaterial Space Frame, with the larger parts being made from a carbon-fibre-reinforced polymer (CFRP) that supplements the aluminium frame.
The CFRP components make up 23%, and the metal parts comprise 75%, of the body-shell weight, with miscellaneous materials constituting the remainder. The R8 e-tron’s forward structure design is classically aluminium. The occupant cell’s dominant material is CFRP, with the tail using both materials. The supporting trunk CRFP insert integrates corrugated crash structures so that the rear can absorb five times as much energy as an aluminium lattice. For the B-posts and rear bulkhead, a new sandwich concept lowers weight by 11.5 kilograms (25.35 lb).