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Exhaust noise control


The ExAct is a dynamic exhaust silencer for all types of internal combustion engines.

It reduces low-frequency noise in real time regardless of engine acceleration.
It simplifies and reduces the size of traditional exhaust lines.

Presentation produit ExAct technoFirst


The device consists of an oscillating flap fixed on an axis and introduced into the flow of the exhaust pipe to produce a sound.
The oscillating flap is driven by a DC motor.
Control electronics control the entire system so as to reduce fluctuations in flow rate and acoustic energy in real time. The system is patented worldwide

Strong points

  • Exceptional attenuation of high level noise in the low frequencies.
  • Decrease in the level of the lines (motor rotation frequencies) at the level of the background noise.
  • Reduction of fatigue induced by low frequencies.
  • Improved alertness by avoiding prolonged exposure to noisy environments.
  • Low energy consumption.
  • Improved acoustic comfort.
  • Has low added mass.
présentation ExAct technofirst


Example of active acoustic attenuation at the exhaust.

Technical characteristics

  • High mechanical and thermal resistance (~ 1000°C).
  • Works with a low power DC electric motor (~100 Watts).
  • Real-time noise control electronic board.