# Hearing Wi-Fi...really? **URL:** \ **Category:** Factual Questions\ **Created:** [June 5, 2007, 12:08pm UTC](https://boards.straightdope.com/t/hearing-wi-fi-really/406820 "2007-06-05T12:08:20Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Garfield226](https://avatars.discourse-cdn.com/v4/letter/g/9e8a1a/32.png) [@Garfield226](https://boards.straightdope.com/u/Garfield226)\ **Post date:** [June 5, 2007, 12:08pm UTC](https://boards.straightdope.com/t/hearing-wi-fi-really/406820/1 "2007-06-05T12:08:20Z")
We’ve had threads on the boards before about people hearing very high-pitched sounds – stuff like TVs that are on mute or computer monitors that are left on. I’m not sure of the science behind that, but I’ve always been able to do it too. Over the past few years though, I’ve noticed a very faint, high-pitched whiny sound whenever I’m using Wi-Fi. It’s definitely coming from the computer (a laptop), and it is very, very faint (it is completely drowned out by my desktop’s fan, for example). It _seems_ to only be present when my computer is communicating with a wireless router – if I turn off the wireless card, the noise goes away – although my evidence of this is just me turning off the wireless card myself, and then back on to see if I could tell the difference (IOW, no double-blind studies or anything like that). Anyhow, it’s not really annoying or anything, and it’s possible it’s all in my head (though I really don’t think so), but I wanted to ask anyway – is it possible what I’m hearing really is the WiFi? ---
**Author:** ![Stealth\_Potato](https://avatars.discourse-cdn.com/v4/letter/s/d78d45/32.png) [@Stealth\_Potato](https://boards.straightdope.com/u/Stealth_Potato)\ **Post date:** [June 5, 2007, 12:25pm UTC](https://boards.straightdope.com/t/hearing-wi-fi-really/406820/2 "2007-06-05T12:25:50Z")
No, I don’t believe it’s even remotely possible. Wi-Fi signals are EM waves; human ears are receptive only to physical waves of compression and rarefaction in the air. It’s more plausible that you might be hearing some electrically-generated oscillation that is produced by some component your laptop’s wireless card when it’s running, but the radio signals themselves will definitely not produce a sound response in your ear. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [June 5, 2007, 12:30pm UTC](https://boards.straightdope.com/t/hearing-wi-fi-really/406820/3 "2007-06-05T12:30:48Z")
It sounds like maybe the soundcard - or some other component of the sound system (including possibly amplifier stages in the speakers or - remotely possible - the speaker coils themselves) - is picking up some electromagnetic interference from the WiFi - in much the same way as mobile phones will cause blips and other noises when placed too close to a computer’s sound systems. ---
**Author:** ![Garfield226](https://avatars.discourse-cdn.com/v4/letter/g/9e8a1a/32.png) [@Garfield226](https://boards.straightdope.com/u/Garfield226)\ **Post date:** [June 5, 2007, 12:35pm UTC](https://boards.straightdope.com/t/hearing-wi-fi-really/406820/4 "2007-06-05T12:35:46Z")
[QUOTE=Mangetout] It sounds like maybe the soundcard - or some other component of the sound system (including possibly amplifier stages in the speakers or - remotely possible - the speaker coils themselves) - is picking up some electromagnetic interference from the WiFi - in much the same way as mobile phones will cause blips and other noises when placed too close to a computer’s sound systems. [/QUOTE] Ah ha. That sounds likely. I’ve experienced the cellphone interference thing before. ---
**Author:** ![KneadToKnow](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kneadtoknow/32/3999_2.png) [@KneadToKnow](https://boards.straightdope.com/u/KneadToKnow)\ **Post date:** [June 5, 2007, 1:25pm UTC](https://boards.straightdope.com/t/hearing-wi-fi-really/406820/5 "2007-06-05T13:25:37Z")
[QUOTE=Garfield226] We’ve had threads on the boards before about people hearing very high-pitched sounds – stuff like TVs that are on mute or computer monitors that are left on. I’m not sure of the science behind that, but I’ve always been able to do it too. [/QUOTE] FWIW, the science behind that is, electronic components (I suspect with most monitors, it’s the electron guns, since every CRT whines at the same frequency as far as I can tell) sometimes make noise in some people’s audible spectrum. Yours and mine, for instance. I can hear those god-forsaken tick-tick noisemakers a local grocery store uses to keep birds from roosting in their eaves, and I suspect that those young-people-only noisemakers that were in the news a while back would run me out of a place as quickly as they would a teenager. The audiologist who tested my hearing a few years ago and confirmed that I can hear sounds at frequencies which normal people can’t described it (only half-joking) as “bat hearing.” ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [June 5, 2007, 1:56pm UTC](https://boards.straightdope.com/t/hearing-wi-fi-really/406820/6 "2007-06-05T13:56:59Z")
[QUOTE=KneadToKnow] (I suspect with most monitors, it’s the electron guns, since every CRT whines at the same frequency as far as I can tell) [/QUOTE] It’s the flyback transformer which also outputs the horizontal sweep in addition to the HV for the CRT anode. The horizontal frequency in a TV is 15.75 kHz, which is within the range of many people’s hearing. Monitors run at higher frequencies, depending on refresh rate. ---
**Author:** ![KneadToKnow](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kneadtoknow/32/3999_2.png) [@KneadToKnow](https://boards.straightdope.com/u/KneadToKnow)\ **Post date:** [June 5, 2007, 2:06pm UTC](https://boards.straightdope.com/t/hearing-wi-fi-really/406820/7 "2007-06-05T14:06:47Z")
Thanks for the learnin’ up, **Q.E.D.**! ---
**Author:** ![St\_Ides](https://avatars.discourse-cdn.com/v4/letter/s/ccd318/32.png) [@St\_Ides](https://boards.straightdope.com/u/St_Ides)\ **Post date:** [June 5, 2007, 3:13pm UTC](https://boards.straightdope.com/t/hearing-wi-fi-really/406820/8 "2007-06-05T15:13:35Z")
It might not be the WiFi either. Core Duo processors have been well known for making a high pitched noise. My laptop emits a high pitched noise under some circumstances (it comes and goes)