A muffler is a series of pipes that are designed and fine-tuned to bounce the sound waves produced by the engine and cancel themselves out. There is a huge difference a muffler can make to the noise level as compared to a car that isn't fitted with one Despite being part of the exhaust system installation, it does not serve any primary exhaust function. Consisting of a sets of tubes, the muffler is designed as an acoustic soundproofing device to create reflected waves that interfere with each other or cancel each other out.