MERCEDES-BENZ has lifted the lid on a leaner and meaner SL Roadster - made for the first time almost entirely from aluminium.

The initials SL have always stood for Sporty and Lightweight - and at around 140 kilograms less than its predecessor the 2012 model will certainly live up to its name.

In terms of rigidity, safety and comfort, the aluminium structure is far superior to the outgoing car's steel construction.

Latest versions of a model that's been around for 60 years will also boast more interior space and even better driving dynamics courtesy of the new BlueDIRECT engines which are more powerful yet up to 29 per cent more economical than the engines in the current generation.

Two engines will be available from launch next July, both with ECO stop/start and 7G-TRONIC PLUS automatic transmission

Thenew V8 in the SL 500 develops 435bhp - some 12 per cent more than its predecessor despite slightly less displacement - yet its pulling power has leapt from 530 to 700Nm and fuel consumption is better by 22 per cent.

And although the V6 in the SL 350 remains a 3.5-litre unit, it delivers 306bhp, a whopping 370Nm of torque and is almost 30 per cent more economical than its predecessor.

This model, despite its improved economy, can accelerate from 0-62 mph in 5.9 seconds, making it three tenths of a second faster than its predecessor, while the SL 500 takes 4.6 seconds - eight tenths less than before.

The new SL is also the first car to be equipped with the adaptive Magic Vision Control wiper/washer system developed by Mercedes, which cleans the windscreen without the familiar splash of water that usually disrupts the driver's field of view.

The wiper blade glides over the windscreen without a sign of a water jet - the occupants can't see anything yet the windscreen is still cleaned.

And the new generation of the luxury sport car can also be converted into an open or a closed concert hall courtesy of a unique FrontBass system, which also makes its world premiere.

Instead of being placed in the doors in the usual way, in the new SL the bass loudspeakers are installed in the footwell in front of the driver and front seat passenger, something not possible with traditional vehicle structures.

The speakers are fitted in two openings in the firewall on either side of the footwell and cavities behind them act as resonating chambers for clear, crisp bass sounds with a high dynamic range.

Mercedes-Benz chief Dr Dieter Zetsche said: "There are around 900 million cars in the world and thousands of models. But there are only a handful of automotive icons. Our SL is one of them.

"It has class, it has style, it is the ultimate in comfort and luxury. But it combines all that with incredible sportiness and dynamism. You would struggle to find a car that embodies Gottlieb Daimler's aspiration more perfectly than our new SL: the best or nothing."