Putting into its pace at Mercedes Technology Center (MTC) in Sindelfingen, Germany, the new SLS AMG Roadster is starting to take shape before its September debut at Frankfurt International Automobile Show. Though development for both coupe and roadster went along side-by-side from the start, engineers at Mercedes-Benz and its Mercedes-AMG performance division took several factors into consideration before launching the roadster. Not just a mere drop-top variant of the coupe, the removal of its roof changed the driving dynamics for the roadster. To counter the effect, Mercedes added a stiffer chassis. Mandatory to any convertible, the test vehicle went through a rigorous phase of simulated rain and cold tests to see if the fabric top hold its integrity. Other improvements include the 250-watt subwoofer of the Bang&Olufsen BeoSound AMG sound system, re-calibrated inline for the addition of wind noise. More details to come as folks at Affalterbach put together the final touches.