Often seen as the default choice for a large, understated family performance car, it’s all change for the new S6 e-tron which uses a pair of electric motors for the first time. While the V8 and V10 engines of its predecessor models are the most renowned and associated with the model, this isn’t the first time that quiet drivetrains have been attached to the name. Since 2019, the S6 Saloon and Avant estate had been sold with a 3.0 litre twin turbo diesel that produced 339 bhp and 516 lb ft (700 Nm).

The electric successor has 496 bhp on call, which can be overboosted to 543 bhp with launch control engaged. The twin-motor setup and all-wheel drive helps the car to reach 62 mph in 3.9 seconds, and will propel it to a top speed of 149 mph flat out. Peak torque is a mighty 620 lb-ft (840 Nm) and there is a rearwards bias to the quattro all-wheel drive system along with staggered tyre sizes that sees wider rubber at the rear. 21” wheels are standard for the model, but air suspension should bring the ride quality that is expected in this class in spite of the enormous rims.

With a 94.9 kWh capacity battery between the axles, a driving range of up to 405 miles for the Sportback and 388 miles for the Avant are attainable. Using an 800 volt electrical architecture, the car can recharge at up to 270 kW on a DC rapid charger, completing a 10-80% top-up in just 21 minutes and being able to add 192 miles of range in just 10 minutes. 11 kW AC charging capability is useful for slightly faster charges at shopping centres, but by my maths a flat to full home charge with a 7 kW wallbox should take just under 14 hours. Regardless, the S6 seems to be a lot more efficient than the 320 mile-capable BMW i5 M60, and the Mercedes-AMG EQE 53 which offers a range of up to 306 miles combined. I got just a little bit less when I had one for a weekend…

Aerodynamics have played a big part in the new model’s efficiency and styling, with both body styles flaunting sleek shapes. Owing to its lifting tailgate, the S6 Sportback replaces the saloon in the range while the Avant becomes one of the best looking estates on the market to my eye, and looks almost identical to the A6 e-tron Concepts that previewed the production models we see now.

Familiar Audi styling features such as the singleframe grille and large bumper inserts dominate the front end, while the narrow LED running light cluster is separated from the main headlight unit. Split lights are splitting opinions, but I personally like them as they remind me of the setup used on the excellent Citroen C4 Cactus…anyway, matrix adaptive LED main beams come as standard for the S6, while the running light signatures at the front and as part of the rear light bar can be customised via the infotainment system.

The new S6 has a long wheelbase with short overhangs, leading to a surprisingly long bonnet for a car that has not been designed to have an engine sitting underneath it. My favourite styling feature is found at the bottom of the doors, with a black trapezoid cutout that rises from front to rear before narrowing and continuing on the other side of the rear wheel arch.

The aero-influence is seen again on the Sportback with its sloping roofline that meets a short rear deck behind the rear axle, while the Avant’s roof falls ever so slightly to make the car cut through the air efficiently and provide enough space for luggage or the obligatory dog that is always said to be found in the boot of a car like this.

Strangely, the quoted boot size for both models is 502 litres but this up to the parcel shelf as opposed to the roof. The Avant has an ever so slightly longer boot than the Sportback, and both cars have folding rear seats that can expand the load space further. There is underfloor storage to be found in the rear, and an extra 27 litre front boot which is accessed by opening the bonnet.

Moving forwards in the interior, the S6 has room for five and an electrochromic roof which dispenses with a roller blind in favour of liquid crystals that can turn the large glass panel from transparent to opaque at the touch of a button. This is standard at launch in the UK as part of the handsomely-equipped Edition 1 specification. The dashboard is virtually identical to the Q6 e-tron SUV that sits on the same platform, and very similar to what is found on the recently revealed S5 Saloon and Avant. This sees two curved displays behind one pane of glass, making up the instrument cluster and the infotainment display.

Also standard at launch is an extra screen for the front passenger which allows them to interact with the infotainment, change the navigation or ambient lighting settings, or even watch some of my videos about cars from another German manufacturer on YouTube.

Of more interest to the driver is the multifunction steering wheel with flat top and bottom sections, along with paddles for instantly adjusting the energy recovery levels - something that I think should be standard for every EV on sale. Optionally available for the S6 are the digital wing mirrors which I'm sure will continue to split opinions. I’ve sampled this system in the original Audi e-tron SUV and it is actually quite a good bit of kit in principle with a clear view, but the displays were mounted far too low on the door cards so it was not easy to get used to. Luckily, Audi have raised the displays to sit on the window ledge, which can only improve usability.

Glass door mirrors are standard, but in a continued break from S-model tradition and as we've seen with the updated e-tron GT, black exterior trim appears to be becoming standard for fast Audis in the UK. The wheels are the main giveaway as to which flavour of new electric Audi you may be spotting on the road, as all A6 S-Line and S6 models get the same front end and four-strake rear diffuser design. I’m usually rather good at spotting the slight differences in bodywork between standard and performance versions of cars, but save for a black lip spoiler on the S6 Sportback, I can’t see any!

The S6 always had subtle exterior tweaks compared to the A6, but the new generation takes the definition of sleeper a little bit too literally. However, it does leave a lot of room for the upcoming RS6 to turn both the design and performance up to 11. Until that arrives, the 2025 Audi S6 Sportback and Avant are the electric interpretation of the much loved fast family hauler, offering high performance levels in a familiar looking package.

For those who like the look of the tech but would prefer a piston engine to power it, the new A7 is on the horizon which will offer petrol, diesel and plug-in hybrid powertrains in saloon/sportback and estate forms. Going forward, fully electric Audis will carry even numbers, while combustion models gain odd numbers.

Launch prices and specifications for the new S6 have been confirmed, with the Sportback starting from £98,275 and the Avant beginning at £100,075 on the road. Spec-for-spec, this means the Audi undercuts both the BMW i5 M60 and Mercedes-AMG EQE 53, although those cars offer 600 bhp from their twin motor powertrains. The S6 launches in Edition 1 specification which includes 21" alloys, air suspension, the electrochromic roof, augmented reality head-up display, Bang & Olufsen surround sound system with headrest-mounted speakers, heated front and rear seats, three-zone climate control, three-screen infotainment and much more. Digital door mirrors, a tow bar, metallic and pearl-finish paints, red leather upholstery and extended warranties are the only options currently available for the S6.

Deliveries are expected to commence in February 2025, although you may not realise when a new S6 passes by owing to how subtly different it is from the regular A6, but perhaps that is a big part of the appeal of the silent super-sleeper.