Memories of the 28th Century

I don’t like noise, and I have a rather broad definition of it. There are many kinds of noise, ranging from dogs howling at nothing to infants bawling to pieces of steel falling on concrete to motorcycles converting gasoline to noise to monster trucks tearing down the road to “wall of sound” style music to evil politicians speaking and so on. It’s Summer, so there are more noisy engines running than there might be at other times of the year, so they are what triggered this rant.

There are several reasons why things are noisy, but the piece of steel falling on concrete is typical, something goes wrong and energy is converted into acoustic waves. When we consider the matter of energy being converted into acoustic waves, because some mistake was made, we define most noise. That is especially true with motor vehicles that make noise.

In order for a four cycle gasoline engine to make much noise with the muffler still on it the engine has to be very poorly tuned. Two cycle engines, such as many motorcycles use are more prone to making noise, but they make more noise when they are poorly tuned. The loudest motorcycles are firing at the wrong point in the cycle, so that much of the energy from the ignition is going right out into the exhaust, instead of helping to push the cylinder. The same can be true of car engines, but it is less likely (see engine basics link below).

But motor vehicles are not the only things that make excessive noise. There are people who crank up music to levels that sometimes exceeds the ability of the sound equipment to reproduce sound, so music turns into undifferentiated noise. And some people find that pleasant. There may be a neurological reason for that problem, but I’m not going to look into it now, because I am a bigot and consider people liking such noise to be suffering from a neurological problem that should be corrected.

I have used power equipment that made considerable noise, but I haven’t done that near other people, and I wore hearing protection, and I cut power when I didn’t need to have the thing running.

Recently, I was thinking about the energy wasted in noise, and I thought about electric and steam engines. Both are quite quiet, and that suggests greater efficiency. I realize that technically steam engines are supposed to be less efficient than gas and diesel engines, but I can’t help but think that the low level of conversion of energy to noise and the much lower amount of friction in steam engines makes them more efficient in actual practice. From what I can find friction is not considered in the theoretical efficiency of engines, even though it is a major factor in most engines.

Another matter that I wanted to touch upon was the relationship between noise and mental health. There have been a number of studies that indicate that there is a negative correlation between ambient noise and mental health, especially among children. I linked a few articles, but search and you will find more. And there is the flip side of that; there is a positive correlation between people who make excessive noise and people with mental health issues, but correlations do not show causes.

There are anti-noise ordinances in many places, but it might be nice to have more. Not only would it lead to better concentration, but there would be a reduction in fuel usage. I am generally opposed to government restrictions on private activity, but noise doesn't do anyone any good, and it does considerable harm.

Maybe I should just move to a place far from noisy things.





http://www.enginebasics.com/Engine%2...st%20Flow.html

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1740306/

http://www.scientificamerican.com/ar...kground-noise/