1590: The Source

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The Source
Why did we even have that thing?
Title text: Why did we even have that thing?

[edit] Explanation

This comic is about experiencing a high pitched hum in an empty room. It refers to the title text in comic 597: Addiction. An "empty-room hum" is a high pitched buzzing noise, which it is suggested results from the brain increasing its sensitivity to noises. (See also other waves in 273: Electromagnetic Spectrum).

Sometimes not everyone can hear "empty-room hum"; however, those who can hear it usually find it immensely annoying. If you do hear the noise, you would like to locate The Source – hence the title of the comic. Hopefully when you find the source, you can do something about it. Or if you don't find it, you can at least be at ease knowing that others experience the empty-room hum, it having been referenced in two xkcd comics now and elsewhere on the internet.

This comic alludes to the perspective of an outside observer who doesn't hear the hum but is watching someone who can hear it: because the sound isn't written out in text, the comic reader at first is confused by Cueball's inexplicable searching.

In the first two frames of the comic we see Cueball trying to locate the direction of the sound, by standing in the middle of the room, turning his head from one to the other side. Finally he walks down a flight of stairs (probably to the basement) and here he locates the source: A machine whose only function is to generate a high pitched hum. The title text asks why on Earth they had such a machine in the first place, which is somewhat difficult to explain and likely the crux of the title text's joke.

Luckily it was thus easy for Cueball to get rid of this sound at the source. But in real life most electronics generate hums and cannot reasonably be turned off without losing functionality. For instance fluorescent lights, phone chargers and computer modems are common culprits, refrigerators and washing machines less commonly. It could also come from outside the house, in which case it will be much harder either to locate the source or to do anything about it. Power lines and transformers are common outside sources.

There do, however, exist devices that are meant to create a high pitched hum, that people might wish to install in their house. These will be humming in the ultrasonic regions, although cheap versions can often be heard by young people. They are typically used for electronic pest control, while slightly lower frequencies which can typically be heard only by young people are sometimes used to repel children. It is possible that someone tried to get rid of Cueball.

There do exist white noise generators (which make equal volume noise on every frequency) and pink noise generators (which make noise that sounds equally loud to the human ear at every frequency) which are used to test recording studios to see if they have good sound quality. It seems unlikely that the device is one of these, as it seems to be designed to generate a high-pitched hum: pink/white noises are categorically and perceptually different from a hum.

The empty white room also could be a reference to a scene from The Matrix Reloaded in which Neo searches for "The Source," though this is likely just a coincidence.

[edit] Transcript

[Cueball is standing in an empty room looking in the direction of the next frame.]
[Cueball turns his head and looks the other way.]
[Three smaller panels with the same total height as the first two frames follows. In the first frame Cueball walks on a grey surface.]
[In the next Cueball is standing between two doors, looking over his shoulder towards the one to the left, but choosing the one to the right behind which a stair is. He is waking towards this door with his hand out towards the knob.]
[In the last of these smaller panels Cueball has just walked down to the bottom of the stairs.]
[Cueball walks towards a machine that is standing near a wall connected to a socket in the wall. On the machine it says:]
High pitched hum generator
[Cueball kneels behind the machine and unplugs it from the socket in the wall.]
High pitched hum generator
[Cueball walks away from the machine, the plug now lying on the floor between the wall and the machine.]
High pitched hum generator

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As soon as I finished this comic, I started to hear it. Please, make it stop. It's not on the basement, nor the attic. It's getting louder. Driving me crazy. Please. Maybe this gun would help me to shut the noise down. Now, where should I aim it? (talk) (please sign your comments with ~~~~)

Very dark humour there from anonymous... I guess it will be to late to help him now. But if he misses he will have even more ringing noises in his ears than after reading this comic. ;-) --Kynde (talk) 12:13, 14 October 2015 (UTC)
Just shoot wherever. If you're lucky, you'll be partly deaf and not hear the hum anymore. -- 13:49, 14 October 2015 (UTC)
No, hearing damage (for instance as a result of loud noise) is what very often causes tinnitus. Jkrstrt (talk) 14:44, 14 October 2015 (UTC)
Thus, it would most likely be a fairly reliabel way to ensure that hear ONLY a high-pitched hum, and nothing else... -- Brettpeirce (talk) 14:04, 15 October 2015 (UTC)

The background noise created by appliances like refrigerators and washing machines is typically generated by their electric motors/pumps which operate at 60 Hz; a frequency I would not consider "high pitched". The only devices I can think of off the top of my head that generate what I would consider high-pitched noise are TVs (both CRT and flat-screen). Smperron (talk) 13:13, 14 October 2015 (UTC)

It's 50Hz over here in Germany (talk) (please sign your comments with ~~~~)
most new transformers are of the switching variety and can be as high as 1MHz. 19:09, 15 October 2015 (UTC)

I can think of only one potentially high pitched hum generator that would look something like that, and I didn't know Cueball lived with a lesbian who uses a symbian. Let alone such a person leaving their rather high wattage sex toy plugged in. Seebert (talk) 13:55, 14 October 2015 (UTC)

I suspect the title text may be a reference to “why do we even ‘'have’’ that lever?” from The Emperor’s New Groove: https://www.youtube.com/watch?v=sw2B9knw58U ZevEisenberg (talk) 14:00, 14 October 2015 (UTC)

I agree, and made my account to make that observation. (Panther) -- Panther (talk) (please sign your comments with ~~~~)

I suspect the title text to be the most common wording for this kind of question, so it could not be a reference to whatever in any way. 14:33, 14 October 2015 (UTC)
That was my first thought too. My second was "I guess they're going to find out." See Chesterton's fence. Wwoods (talk) 14:58, 14 October 2015 (UTC)

Here is a hum generator for you, from a noise generator website: http://mynoise.net/NoiseMachines/60HzHumNoiseGenerator.php 15:15, 14 October 2015 (UTC)

"There do, however, exist devices that are meant to create a high pitched hum, that people might wish to install in their house. These will be humming in the ultrasonic regions, although cheap versions can often be heard by young people. They are typically used for electronic pest control. Maybe someone tried to get rid of Cueball." - while I don't think the comic is intended to reference this, the above selection somehow almost entirely surrounds the concept of an ultrasonic youth-control device without actually involving it. (Probably because the editor(s) involved don't actually know about it. Maybe now they do.) 15:11, 14 October 2015 (UTC)

I thought there might be more to it than just referencing high pitched noises inside a household (yes, I can hear it now as well, thanks a lot), so when I read the title of the comic, I thought it might have something to do with a source code of a program... Sometimes the program does something irritating that it should not - so in the first two frames Cueball is trying to locate the problem and then he walks throught the program to finally locate a piece of code that should not be there. And in the image title he says "Why did we even have that thing?" - as in you sometimes come across a piece of code that is useless and you don't even know what it is doing there. But who the hell knows. 15:13, 14 October 2015 (UTC) 9of8

As a programmer, you have a tendency to see all problem solving tasks in analogy with either programming or debugging. So do I, and so does Randall. But that doesn't mean that analogy is the point of anything Randall writes about solving any problem; it's just always there in the background, slightly influencing the way he describes things, in ways that people with similar backgrounds will pick up whether it's intended or not. In this case, I don't think it was intended, or adds anything to the joke. A doctor writing the same comic might have the main character act slightly differently in diagnosing the problem, and use slightly different words, but the point would be the same as it is here. -- 17:53, 14 October 2015 (UTC)
"The thing that generates a high pitched hum is broken, can you fix it?" - "What does it do?" - "We don't know, it's always been there and the guy who installed it quit 10 years ago.." - "If you don't know what it does, how do you know it's broken?" - "It stopped generating a high pitched hum and we're worried about that.."...ask anyone involved in some kind of engineering and they probably have an example that is analog to that description so it's not that far fetched. This can be in programming, networking, robotics at NASA... 08:42, 16 October 2015 (UTC)

I had once thought about why do I sometimes hear high pitched noise. We have all kinds of tiny random noises all around us. Hums, pulses, bugs, elecs,etc. Human ear canal is a few centimeters long. And it has resonant frequency around 2000~3000Hz and its odd multiples. So, my conclusion was, of all the tiny noises the 2000(or 3000)Hz and its third(6000 or 9000Hz) and fifth harmonic(10000 or 15000Hz) frequencies,or even higher harmonics would get amplified by resonance. Pls correct me if I'm wrong. Thanks. Parsec (talk) 15:30, 14 October 2015 (UTC)

That's all true, but your cochlea, auditory processing brain modules, etc. are all trained from birth to respond to the input they get from that resonant canal, so that amplification is already taken into account (i.e., those frequencies have higher activation thresholds and more opponent dampening, which counters the physical resonance). If your ear were radically reshaped in adulthood to have different resonant frequencies, it would take time for your brain to adjust, and it would do so imperfectly, but since this normally doesn't happen for most people, we don't notice any such effects.
This does raise the question of whether one cause for tinnitus might be your brain overcompensating for loss of high-frequency inputs due to aging and/or damage. As far as I know, that hypothesis has been raised multiple times, but not yet conclusively tested, but you may want to search for yourself. --- 17:53, 14 October 2015 (UTC)

Phillip Glass: Changing Opinions "Gradually....we became aware...of a hum in the room.... an electrically hum....in the room.It went mmmmmmm mmmmmm mmmmm mmmmm mmmmm. https://www.youtube.com/watch?v=UC01ZVEXCBY

Gradually We became aware Of a hum in the room An electrical hum in the room It went mmmmmm

We followed it from Corner to corner We pressed out ears Against the walls We crossed diagonals And put our hands on the floor It went mmmmmm

Sometimes it was A murmur Sometimes it was A pulse Sometimes it seemed To disappear But then with a quarter-turn Of the head It would roll around the sofa A nimbus humming cloud Mmmmmm

Maybe it's the hum Of a calm refrigerator Cooling on the big night Mmmmmm Cooling on the big night Maybe it's the hum Of our parents' voices Long ago in a soft light Mmmmmm Long ago in a dimmed light Mmmmmm

Maybe it's the hum Of changing opinion Or a foreign language In prayer Mmmmmm Or a foreign language In prayer Maybe it's the mantra Of the walls and wiring Deep breathing In soft air Mmmmmm Deep breathing In soft air Mmmmmm -- Singmaster (talk) (please sign your comments with ~~~~)

For what it's worth, my first interpretation of the comic was that he was in some kind of ultra-quiet room (thus the bare walls and multiple doors) and Cueball was just hearing the inherent high-pitched buzz, created by your own body somehow (I've heard different explanations from different sound teachers), that one still hears in those rooms. But that was just my take. It made me chuckle. Xopherok (talk) 22:51, 14 October 2015 (UTC) xopherok

Many types of power supplies for powering DC devices (like laptops, TVs etc.) from mains power generate high pitched hums. These hums are supposed to have a frequency above the audible range (making them inaudible to humans), but it's very common for a slightly faulty unit to actually create a constant audible very high pitched hum. 00:36, 15 October 2015 (UTC)

Hmm.. I feel like we still have not found the deeper layers of that comic. IMO it is not about trying to figure out what room or device the comic has similar effects in real life, but rather see them as imaginary. I personnally thought of a short story by Kafka, The Burrow, which features a self-aware animal which has build the perfect holt, but starts to hear a high-pitched hum. It is driven insane by it since it appears to be in permanent danger, but it is unable to locate the source. (Not saying Randall thought of that story.)

Maybe the comic ironically portrays the thoughts of person looking through their house for a undetectable hum which may even be imaginable. That person wishes for the sound coming from such a noise generator which can be easily switched off. Afterwards, the person would wonder why they even have such a generator. Obviously, this remains a wish (which is ridiculous if we see it depicted that clearly) of a increasingly insane person. --

That is a nuclear device that keeps all the ghosts trapped. Don't disconnect it!! 10:02, 15 October 2015 (UTC)

When I read this comic, I interpreted the humming noise to be "That high-pitched noise in empty rooms," which is referenced in 273: Electromagnetic Spectrum. Rsranger65 (talk) 22:09, 15 October 2015 (UTC)

Most humming devices are humming because of the designer of the device has forgot to isolate it or the components well enough to be quiet. Problem is, that if you would be able to turn ALL ambient sounds off (AC, Computers, Lights), you would still be hearing the humming sound of yourself. The ear / brain hear the silence, and tries to enhance/interpret/amplify, so it creates sounds/humming/noise that is not there at all. Try to listen to "nothing" in a quiet room, combined with trying to look, when having your eyes closed. After a little while, you will hear strange sounds and see strange patterns. Try not to get mad after learning this. It can take time to get used to knowing about these sounds and patterns. Just think about how cool it is instead of scary, and your mind will be OK with it. 12:18, 16 October 2015 (UTC)

For me, I first thought of retro computer games, like Duke Nukem, these games had lots of weird stuff that did nothing but generate noise like this. Jack (talk) 13:23, 16 October 2015 (UTC)

I keep checking mine, but I guess it runs on batteries since I still hear it. -DanB (talk) 17:44, 16 October 2015 (UTC)

Oh, goddammit. I never noticed that before. Go onto xplainkcd, now I can't stop hearing it. Argh! Sensorfire (talk) 04:16, 22 October 2015 (UTC)

This is exactly what happened to my Samsung monitor before it died. I was going to bed one night and this high-pitched noise was driving me insane. I turned my PC on, only for the monitor to go black. The problem with these high-pitched noises is that they're hard to locate. - 22:04, 26 October 2015 (UTC)

For those of us of a certain age, there was a very specific high-pitched sound in almost everyone's daily environment: the horizontal line rate (sometimes called retrace frequency) of analog televisions. For the U.S. NTSC system, this was about 15.7 kHz (PAL: 15.6 kHz). Televisions almost inevitably produced this sound because the "flyback" transformer which produced the voltage used to steer the electron beam back and forth underwent some mechanical stress each time the beam was rapidly swept back for the next line ("retrace"), thus moving some air and creating the sound. This pitch is high enough that in a room full of people there would be some who could and some who could not hear it. The sound is also quite similar to the perceived sound many people with tinnitus experience. Between these two effects, it was easy for arguments to start about whether the sound was real or not. I was always very sensitive to the sound and could tell from several rooms away if a television was on. (Also: love the Philip Glass, both original and choral versions.) 20:43, 2 November 2015 (UTC) There's a storyteller by A.E. van Vogt, "The War against the Rull", which involves a young boy seeking the source of an almost subliminal noise.

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