Audi e-tron GT: the new sound of electric performance

Changing the tone for all-electric driving

For any car, its engine tone defines its character. It’s a unique emotional sound that sits somewhere between the head, the heart and the gut. In the Audi e-tron GT, it also means blending and balancing the dual-edged sportiness and sophistication of its ‘gran turismo’ character.

Using the e-tron Sport sound pack (an option on the Audi e-tron GT, but standard on the Audi RS e-tron GT), you can switch between the ultra-quiet ‘Efficiency’ mode – which uses the car’s exterior speakers to project a subtle tone that informs and warns nearby road users of the car’s presence during city or suburban driving – or a more vibrant ‘Comfort’ tone that transmits a bit more noise into the cabin.

Flick down to ‘Dynamic’ on the Audi Drive menu, though, and the full power of the Audi e-tron GT’s virtual engine tone is broadcast directly into the cabin using large speakers in the rear doors. Powerful, sporty and nuanced in equal measure, the tone rises and falls, ebbs and flows, based on the rotational speed of the electric motors, the accelerator position, and the Audi e-tron GT’s speed.

On an amazing open road, it gives you all the feedback you need, and is the perfect acoustic expression of the Audi e-tron GT’s sporty and progressive ‘gran turismo’ character.

The substance behind the style

So, how was the Audi e-tron GT’s virtual engine tone shaped, crafted and composed? As with many elements of Audi’s approach to electric design on the Audi e-tron GT, Audi’s sound engineers ripped up the rule book and started from scratch with a clean-sheet approach.

“The sound of a car has a lot in common with music,” says sound engineer Rudolf Halmbmeir: a musician in his spare time, with his own private recording studio. “We deliberately avoided imitating a combustion engine or a spaceship from a science fiction movie. Instead, we developed a sporty sophisticated sound that combines familiar patterns with new futuristic elements. We tried to let the car decide what it sounds like and find the recipe that achieves that best.”

Inspiration came from unusual places. “To find the foundation sound of the Audi e-tron GT, I tried all sorts of instruments: from the violin to the electric guitar, all the way to the didgeridoo, but none of them were suitable,” Rudolf explains. “Then I came across a piece of plastic pipe, 80mm in diameter and 3m long. I attached a fan at one end, and it had a specific growl that felt deep and alive. We knew straight away that we’d found the foundation of the sound.”

Other unique sounds hidden deep with the complex multi-layered tone are a cordless screwdriver and a model helicopter. “The recordings are made up of around 32 elements, which are each converted into short loop-able soundbites,” says sound engineer Stephan Gsell. “As the sound is driven by vehicle data the repetition is increased when the acceleration or speed increases. It’s continuously recreated as the algorithm mixes and prioritises the individual sounds differently.”

The end result blends low frequencies that imply serene power with mid-range frequencies that express sportiness and agility, as well as high frequencies that add a dash of sonic brilliance and electric spark.

The sound of silence

French composer Claude Debussy once described music as: “the space between the notes”. It’s the same with the Audi e-tron GT. A potent soundtrack is all well and good on the right road, but the other benefit of an all-electric car – especially a refined ‘gran turismo’ like the e-tron GT – is the option to appreciate the calming near-silence of all-electric drive as you waft along the motorway or city streets.

The challenge facing today’s car engineers in the quiet hum of an all-electric age is how to reduce or eliminate the tyre and wind noise that naturally occurs as any vehicle moves through the air or along a rough asphalt road. Audi has long been praised for the ultra-high levels of refinement and built quality in its cars, and Audi’s engineers took things to the next level with the Audi e-tron GT.

Built in Audi’s Bollinger Hofe small-series-run production plant – which previously produced the Audi R8 – the Audi e-tron GT is manufactured using a high-tech fully-automated production line that guarantees even greater levels of accuracy, with skilled hands-on craftsmanship for the finishing touches. Its all-new inline measuring process, for example, tracks the assembly of the ultra-high-strength steel and aluminium chassis and body at 350 points to an accuracy of +/- 0.20 millimetres.

At the end of the production line, each and every car is then driven for a total of 25 miles on a mix of motorway and urban roads, with highly trained engineers listening out to ensure there are no creaks, rattles or parts rubbing together.