Hacker News Reader

Comment by withinboredom | Hacker News Reader

I nearly fell out of my couch laughing! I guess none of these people have ever lived on a boat. The hum is/are boats, you can hear them pretty far inland too, especially late at night!

View on HN

I nearly fell out of my couch laughing!

I lived in 3 different islands with tons of boats (from cruise ships to yaughts, to tankers, to cargo), have never heard "the hum" (nor has anybody else complained or mentioned any of the thousands there), don't even know what you're on about...

Not everyone can hear it (like my wife) and if you live on the water, it's pretty obvious it's the boats. It's when you don't live near water and you hear it at 2am, and go "wow, that's really interesting," and then go to sleep.

I literally haven't thought much of it until reading this article, other than passing observations. For example, I've noticed it's not audible in every house, and usually not audible on the ground floor when it is audible on other floors.

>it's pretty obvious it's the boats

What exactly about "the boats" would it be? The motor? The propeller?

Doesn't sound like a thing...

It definitely is a thing; see my reply above. It's the engines. I was able to experimentally connect /one/ source of hum to tug boats specifically. Interestingly, though, the huge container ships that passed by did not make an audible noise.

One unfortunate effect of the name "the hum" is it kind of implies a single source. Realistically, it's probably a whole collection of sources, including some real physical phenomena, and some tinnitus-like audio hallucinations.

Not sure what it is specifically. When living on a sailboat, under the waterline, you can hear it quite distinctly.

Feel free to update the wiki https://en.wikipedia.org/wiki/The_Hum instead of squandering all that knowledge!

Ah that's a good idea. It doesn't bother me at all (since I know what it is, it's rather comforting and brings back good memories) but never considered that it might bother people who have no idea what it is (I've heard it as far as 20mi/30km away from a shipping lane in the US.) I live about 1mi/2km from a canal that regularly has barge traffic late at night. I'll see if I can find a mic or equipment that can pick up the hum, then do a little study. It'll be fun and also make it easy to reproduce around the world.

Edit: I've also considered that the frequency could be a resonant frequency in the human body for some people, making it seem unnaturally loud. My wife can't hear it.

> I've heard it as far as 20mi/30km away from a shipping lane in the US

Have you taken a look at The World Hum Map (linked from the article)? There are a lot of data points that are deep inland, way more 30 kms. For example there points in the Australian outback, and all through the "flyover states" in the US.

I did, a lot of cities are near navigable rivers that barges go down. I don't think all hums are boats, but I'd be willing to venture that most near waterways are.

I work in acoustics. Very familiar with data acquisition and processing. Hit me up if you need any processing help.

That would probably end up getting reverted because wikipedia forbids original research

For coastal city dwellers, I think it's likely that marine traffic is a major source of the hum, but the world hum map has a lot of reports from far inland that aren't explained by that.

I used to live in a place that overlooked a shipping channel. I could perfectly tell you when a tug boat was near based on the low, resonating hum of its engines. I confirmed that theory with marinetraffic.com, and it was a relief to know I wasn't hallucinating.

I have since moved, and started hearing "the hum" in March. I'm now about five miles inland from that port, but I hear the hum louder than I ever did from passing boats. I can't match it to any specific marine traffic, although the sound is nearly identical. It could be nautical, or it could be some other industrial noise, or it could be something like tinnitus.

My wife can't either either sound.

I’m curious, can you hear electronics? I can hear a CRT TV from almost 100ft away (the TV being muted, of course) and can tell you when it’s off and on without seeing it (it used to be a fun party trick back in the day). I can also hear capacitors in general if I try (but I just tune it out or I would go insane).

Those “how old is your hearing” sites peg me at 14 though I’m actually double the age and then some.

Yes, I can hear the high-pitched CRT TV noise. And also the high-pitched squeal that some CFL-backlit LCD monitors used to make. I'm not sure if it's that my ears are better, or if I'm just hyper-sensitive to sounds that other people filter out subconsciously.

Why would people in the same room match the sound of the hum to different frequencies? And why would no one be able to record the hum, even with "sophisticated audio equipment"? It seems like these two things would rule out nearby boats as the cause.

I suspect it’s likely to some resonance in the human body that not everyone will have an affinity for. Such that the frequency could be extremely low and it causes a cavity (like a sinus) to resonate and your ear picks it up. I don’t have any proof of that, but it’s a possibility.

Reply on news.ycombinator.com