This product answers the concrete challenge of achieving the sound signature of a great sports car with an exhaust system that fits a medium-sized family car.

The “box in a box” is a distinctive and unique feature: it contains a silencer inside a silencer. The inner silencer contains a diffuser and allows for a uniform and turbulence-free flow distribution to the four tailpipes. 

The remaining volume is generated by carefully tuned pipes, perforations and absorption material. The sound is refined to achieve the right level of 'aggressiveness'. Two electronically actuated valves work to vary the sound depending on the driving style.

The modular silencer can be used on a range of different engines on the same vehicle platform. It outperforms similar silencers with regard to radiated noise thanks to its carefully designed shape and reinforcement patterns. Optimised weld joints and slip joints make the design robust and durable for the vehicle's lifetime, even with gas temperatures in the tailpipe tips as high as 700°C.


  • Modular silencer concept for both comfort and sporty sound systems
  • Dynamic sporty sound design through ‘box in a box’ regulated by electric valves in the tailpipes
  • Optimised silencer housing minimising radiated noise
Bosal Emission Control Systems: acoustic innovation "box-in-a-box".