A subtly aggressive front bumper, menacing grille and rear diffuser with quad exhaust pipes let informed observers distinguish the S6 from its humbler A6 sibling, as do 19-inch aluminum wheels and aluminum side mirror covers.
The big difference between the two, of course, is what lies under the hood. Whereas the A6 uses four- and six-cylinder engines, the S6 packs a potent twin-turbocharged 4.0-liter V8 that generates 450 horsepower between 5,800 and 6,400 rpm and 406 lb-ft of torque from 1,400 to 5,700 rpm. That's enough to propel the sport sedan from zero to 60 mph in 4.4 seconds and on to a top speed of 155 mph.
The V8's partner in speed is a seven-speed S-tronic dual-clutch automatic that serves up smooth but rapid shifts and can be controlled manually through steering wheel-mounted paddle shifters. Audi's quattro all-wheel-drive system helps the S6 conquer inclement weather and also improves handling by sending torque to the outside rear wheel to cut down on understeer in turns.
Despite its performance credentials, the S6 is no gas guzzler - it's rated at 18/27 mpg - due in part to a cylinder deactivation system that essential turns the engine into a V4 in low-throttle highway driving. Known as Cylinder-on-Demand, the setup employs active noise cancellation technology and active engine mounts to eliminate any NVH issues that would be uncouth in such a premium vehicle.
The S6 rides on a full air suspension with adaptive dampers, which can both be adjusted to suit the driver's preferences with a Drive Select system that also controls throttle response, steering effort and shift calibration.
Impressive Inner Sanctum
Aesthetes will find much to like in the cabin, which features organic lines rendered in rich soft-touch materials and set off by fine wood and metal trim. Supportive sports seats wrapped in cross-stitched leather, a three-sport multifunction steering wheel and a S-line instrument cluster are classy reminders of the S6's sporting intentions.
Being a modern Audi, the S6 is equipped with MMI, or multimedia interface, which includes an eight-inch pop-up display, a five-inch information LCD display and an optional heads-up display for the windshield. The MMI also boasts an industry first: the ability to recognize driver handwriting via the touch input pad, allowing for the input of both navigation and telephone information.
The S6 comes standard with Audi connect, which offers in-car WiFi along with real-time localized weather, news and live fuel prices. When equipped with an optional navigation system, the system includes Google Earth integration - complete with panoramic views and high-resolution 3D satellite and aerial imagery.
Standard and Optional Features
The S6 is offered in two trim levels called Premium Plus and Prestige, respectively.
The Premium Plus comes standard with a long list of features including xenon plus headlights with LED daytime running lights, automatic headlights, LED tail lamps, power-adjustable, power-folding, auto-dimming, heated door mirrors with a memory function, heated windshield washer nozzles, a body-colored spoiler, four-zone automatic A/C, a flat-bottomed steering wheel, a sunroof, an auto-dimming rear-view mirror, Valcona leather upholstery with contrast stitching, heated twelve-way power front seats, navigation with voice controls, Audi's MMI touch with handwriting-recognition technology, a seven-inch touch screen, a ten-speaker stereo, keyless entry and start, adaptive cruise control, a HomeLink transceiver, parking sensors on both ends, a rear-view camera, automatic headlights and rain-sensing wipers.
The S6 also comes with Audi side assist - which monitors the blind spot areas and fast-approaching vehicles - as well as Audi pre sense rear, which helps mitigates the consequences of a rear-end collision by closing the windows and sunroof, tightening safety belts and applying partial braking power.
Stepping up to the Prestige trim brings full LED headlights, a power trunk lid, rear sunshades, LED ambient lighting and a heads-up display.
S6 buyers can deck their cars out with a plethora of cosseting optional features and packages. The list of standalone options includes several different alloy wheel designs, paint colors and rear side airbags. Additionally, many of the features that come standard on the Prestige trim can be added to Premium Plus models at an extra cost, including the Bose surround sound system, the rear sunshades and the LED headlights.
The Cold Weather Package includes heated rear seats as well as a heated steering wheel. The Black Optic Package brings body-colored door mirrors, gloss black trim around the grille and around the windows and 20-inch alloy wheels wrapped by summer performance tires.
The Driver Assistance Package includes a top and corner view camera system, adaptive cruise control with a stop and go function, active lane assist, high-beam assist, and Audi's pre-sense plus technology.
Buyers looking for a sportier ride should check out the S6 Sport Package, which brings a sports differential, a custom exhaust line and a more responsive power steering setup.
Finally, Prestige models can be ordered with a Bang & Olufsen sound system and night vision.
All S6 models are fitted with dual front, front knee, front side and full-length side curtain airbags. Rear side airbags are optional. Traction and stability control systems, electronic brakeforce distribution and a tire pressure monitoring system are also included as standard.
Optional safety features include active lane assist, which warns the driver when the S6 is wandering into an adjacent lane and can even gently steer the car back into the original lane. There's also Audi pre sense, which can detect obstacles in front of the S6 and apply the brakes to prevent a crash or mitigate its severity. Finally, Audi side assist alerts the driver when a vehicle is in one of the S6's rear blind spots.
Like other Audi "S" models, the S6 is aimed at the gap between the base-engine and performance models of competing brands. As such, the Audi is aimed at the Mercedes-AMG E43 and the BMW M550i.