Does White Noise Disturb Others?

The short answer to this question is no, it does not.

Having opted for delivery method #3 of my white noise generator, the next question that came to mind is whether this would disturb others. How’s that for a sense of irony?

Refer to a few posts back, the white noise generator basically involves a computer program that pumps out white noise over a variety of frequencies and amplitudes. This is an idea I wish I had thought of years earlier, but it’s better late than never – and is especially applicable in a chronically noisy city like Shanghai.

Earplugs can still come in handy if the computer is hooked up to a couple of tweeters and large sub-woofers that pump out the white noise all over the spectrum. That is, the sound comes out on external speakers (as opposed to headphones, Iphones, blackberries, etc.) and I wear earplugs while sleeping next to the speakers.
What it amounts to, at least in theory, is that the white noise is gonna be LOUD !!

But hopefully not loud enough to disturb the neighbors. If it does disturb them and they come a knockin’ over, then I won’t be able to hear a damn thing!! This whole argument was explained in the last post, so it’s crucial that nobody gets disturbed by the white noise as I’ll effectively be sealed off from any knocking sounds once the generator is turned on for the whole night or for my afternoon nap.

The irony here is that white noise is still noise, and it may be a form of noise pollution for others who are used to hearing all the noises in Shanghai at night, and not used to hearing white noise from someone else’s apartment next door.
It may be possible that others don’t hear the white noise as white noise, especially the bass.

The bass may come across as a rumbling sort of hum, like an air conditioner. At any rate, I had to test this out, so I cranked out the white noise real loud and stood in different rooms and various outside spots to simulate what a neighbor might hear. Turns out I could barely hear anything, so I think this method is good to go.

Actually, we can use a simple mathematical argument to show that the white noise won’t have much of a chance to disturb others.

From physics, we know that the “loudness” of a sound is really the intensity: the power per unit area, or watts per square meter. We also know that this follows an inverse square law, where the intensity decreases by a factor of 1 / ‘r squared’ where ‘r’ is the spherical radius from the source.

For example, if a subway is 100m below ground and it emits some intensity at the source, then the actual intensity of that subway as I hear it is only 0.0001 or one ten-thousandth of that. Sounds small, but it’s enough to wreck my sleep, especially the damn bass rumbling. So the idea is that my speakers match the intensity of what I hear. If a neighbor is 10m away from my speakers, he will pick up the intensity from my speakers as 0.01 less compared to me. So he REALLY hears 0.0001 * 0.01 = one-millionth of the sound of the subway at source, as generated from my speakers. The hope here is that this is small enough to be negligible.

Another less complicated way to look at it is that when the neighbor hears both the subway rumbling and my speakers simulating this, the sound he hears from the subway is 100 times louder than from my speakers. Viewed this way, the speakers should be negligible for him relative to the subway.

We can also use logarithms and decibels to explain further, but I think I’ve bored you with enough math already.
The point here is that the white noise from the speakers doesn’t have to be very loud at all, just enough to match the intensity as I hear it from some distance ‘r’ away from the source of the nuisance --- in this case the rumbling subway or train carriage.

We’re not exactly putting on a rock concert in my apartment here.