What do you think about noise? Often it is really annoying – but sometimes it is very acceptable: When you´re on a rock festival or when you´re driving a sports or a supercar.
So from a medical point of view there can not be a difference between noise from a fighter jet and noise from an exhaust. Both are loud, both are noise within your ear. So what´s the difference?
The only difference is, what we think to hear and what we connect with that sound. A roaring V8 or a screaming flat four means always fun and a great one to drive. You know what kind of car it is and what it´s capable of.
So we enjoy this noise as a fun factor and a a kind of enabler for getting the next adrenaline shock.
Just a loud noise somwhere in the city or a landscape? That is acceptable when it is for a short time and when it is in a not to loud level. But every two minutes a jet above your sleeping room or a train passes through your living room does not mean fun. It means pathogenic noise that is a serious problem.
The point is: For an normal citizen, not a car enthusiat, the exhaust melody is just another source of noise. So close the valves when you are in a living area and open them, when you´re on that road with all the great corners!