Yes and I can hear high pitch noises from many electronics but can easily tune them out.
When I was a kid, I used to hear the high-pitched squeal whenever the old B&W TV at home got turned on or off. Pretty much had forgotten about it until I read about the ultrasonic ring tones some kids use. I got on a website and checked my hearing- nothing over 12 kHz! Oh, well.
I used to teach high school science. It was fun surreptitiously sounding a ring tone from my computer while the kids were taking a test and watching some of them squirm and look guilty (they weren’t allowed to have phones on in class back then)!
What is making the actual audible noise? Are the large changes in the electromagnetic field actually causing the wires in the coil, or the iron core itself, to vibrate back and forth in response?
I’m wondering how practical building a silent flyback transformer would have been.
I think it’s the core mechanically vibrating. By the way it’s made of ferrite, a ceramic mix of metal oxides that is a poor electrical conductor. Transformer cores look like short circuited windings in general, and they get made to have minimal long distance conductivities to fix that. At lower frequencies making them of stacks of separate metal leaves is good enough, but at higher frequencies materials like the ferrites are necessary.
Huh. I figured it didn’t matter if it was conductive, since the windings themselves are coated in an insulator. I guess the core’s role would be, uh, short circuited were charge able to flow freely through it.
It’s typically a magentostrictive effect. Also, the cores are generally split, which doesn’t help things any (the two haves tend to rub against each other).
Hello–for the posters on this thread for whom high-frequency sounds are painful: have you recently purchased a flat-panel HDTV that you can comfortably listen to? If so, what make/model/year? Is it wall-mounted? I just purchased a 32" LG HDTV (720 pixels, 60 hz) and it produces a shocking amount of high frequency noise. It is going back to the store. I used to have this problem with CRTs, but in recent years have not encountered any “noisy” monitors or TVs. Thanks for any recommendations of makes/models. BTW, I have my PC monitor (Dell) set to 72 hz which makes it completely “quiet” for me.
I’ve been able to hear it for years. I just assumed everyone could hear it.
I remember this as a child.
In South Africa we had the PAL system, 625 lines, 25fps.
Even with the sound off I could hear if the TV was on in another room by the distinctive high pitched whine of the screen.
As I got older, I stopped hearing it… apparently we lose the ability to hear high frequencies as we age.
That, and probably my tinnitus caused by being a bassist who had to stand next to the drummer on stage 
I remember that, and the buzz of fluorescent lights.
What’s a youngster like that doing around a CRT?
[checks OP] And multiple CRTs?
Or, really, anyone of any age… do they work in an antiques store?
eta: Just realized this got bumped from six years ago, but even then nearly all those “TVs and monitors that were as deep as they were tall” had been replace with flat screens long before.
CRT TVs in good condition are selling for high prices thanks to millennial retro gamers. I see them listed on eBay marketed as “Retro Gaming TVs.”
When I had a CRT TV in my room as a teenager, I could definitely hear the whine. It’s been years since I’ve owned a CRT or even been around one that I know of, so I don’t know if I can still hear it or not.
I heard them whine. I worked with a lot of different video equipment in the 70s and 80s, there were a variety of whines, sometimes a warning before they smoked. This is just another thing kids won’t understand, like a portable TV that weighs 75 lbs. Went to a party at a friend’s house couple years back, he brought a couple of TVs outside to watch football, one he put on top of his grill (not in use) and used top duct tape to hold it down so the wind wouldn’t blow it over. We marveled at the idea of a TV that could be blown over by the wind. And another guy has in his garage an old invention, two TVs, one with a good picture, but no sound, and the other with good sound and no picture. Used to see people resort to that combo more often once upon a time.
I remember the Apple monitors of the late 1980s/early 1990s had a very noticeable whine. One of my middle school teachers said she could tell when someone forgot to turn off the monitor of the classroom computer because she could hear it.
Anybody know why giving the CRT a good WHACK (bottom-right side was effective) would sometimes calm the whine a bit? When I was young we had a 13" B&W TV that would respond to that persuasion, and I swear I’d had computer monitors that responded the same way, but it’s been a very long time.
I had scary good high end hearing when younger - When I was 35 we had a neighbor with a motion sensor to scare away dogs peeing on the lawn that would emit a very high pitch when triggered. I couldn’t walk past that house; my spouse was like, “what? I don’t hear anything!” I could hear any and every misbehaving CRT (and not all of them did it).
25 years later I just listen to my piercing tinnitus all day 
‘weeeeeeeeeee’
I could definitely hear it in my younger days, but now that the tone matches my tinnitus, I hear it all the time whether or not there is a monitor on.