Are most kids able to hear the supposed "high-pitched" CRT noise? - AVS Forum | Home Theater Discussions And Reviews
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post #1 of 37 Old 04-29-2015, 08:20 AM - Thread Starter
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Are most kids able to hear the supposed "high-pitched" CRT noise?

This makes no sense to me, as based on the way people have described the noise (people talk about how they wanted to run out of the room crying when they heard the noise, or how it would give them major headaches), if most kids were able to hear it, no kids would ever have watched TV back in the days when CRTs were ubiquitous. But we know that's not the case, as most kids watched tons of TV (not to mention played tons of video games). Personally, I don't remember ever hearing this noise, and I started watching hours upon hours of TV from a very young age. And I wasn't a kid who listened to things with the volume turned up, either. I had the TV on a pretty low volume and I never listened to blaring music. My hearing tests were always fine.

Is it just the rare person who is born with exceptional hearing who can hear that frequency?
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post #2 of 37 Old 04-29-2015, 10:45 AM
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Probably a failing flyback transformer.
Some could hear it, some could not.

I could... and it was annoying. $20 and few beers for my friend resolved the issue.
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post #3 of 37 Old 04-29-2015, 11:00 AM
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Others can hear those frequencies, so more likely a sensitivity like this poster's genetic Tinnitus:

Sony Trinitron KV-32XBR200 adjustment and flyback noise

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post #4 of 37 Old 04-29-2015, 11:10 AM - Thread Starter
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Still doesn't make sense to me. Again, if it's so bad and kids in particular can hear it, no kids would have been watching TV. Saturday morning cartoons would have gone out of business. Rather than sitting around watching TV/playing videogames, kids would have avoided the TV at all costs.

They claim the frequency is well within normal human hearing, yet no kids I ever knew ever complained of it.
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post #5 of 37 Old 04-29-2015, 12:44 PM
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Again... it wasn't "bad" unless, you had a sick TV.
OTOH, back in the 60's who cared or complained if there was a "whine". We spent most of our time outside anyway. But, we were thankful that a neighbor had a color TV.
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post #6 of 37 Old 04-29-2015, 12:48 PM
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I could always hear it. Still can. I could tell a TV was on, even when it was muted as I walked down a hallway before turning into the room.

But it was never something that was so bad that it would drive you from the room. It was a subliminal annoyance that you got over in 10 seconds if you ever really mentally acknowledged it at all. I agree with the other posters, anything so bad that you couldn't concentrate on the TV points to something more abnormal than usual in the health of the TV.
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post #7 of 37 Old 04-29-2015, 02:20 PM
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Thank goodness we now have LCD's
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post #8 of 37 Old 04-29-2015, 03:42 PM
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What doesn't make sense to you? We're telling you that some folks are sensitive to it - but a vast minority. Or the transformer is wacky or power supply undersized in the design.

I've got an RCA HD CRT that is louder than usual, bugs me some when there's quiet scenes. But this was one of those inexpensive Walmart special TVs near the demise of HD CRT TVs. I think it has an undersized power supply due to the way it 'breathes' with scene contrast (I've seen this with economy CRT TVs). But hey I got it free and it gets light use as a bedroom TV. All of my other CRT TVs and PC monitors are fairly quiet and contrast stable [Panasonic HD, Sony, and older RCAs].

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post #9 of 37 Old 04-30-2015, 04:02 AM - Thread Starter
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Quote:
Originally Posted by Floydage View Post
What doesn't make sense to you? We're telling you that some folks are sensitive to it - but a vast minority. Or the transformer is wacky or power supply undersized in the design.

I've got an RCA HD CRT that is louder than usual, bugs me some when there's quiet scenes. But this was one of those inexpensive Walmart special TVs near the demise of HD CRT TVs. I think it has an undersized power supply due to the way it 'breathes' with scene contrast (I've seen this with economy CRT TVs). But hey I got it free and it gets light use as a bedroom TV. All of my other CRT TVs and PC monitors are fairly quiet and contrast stable [Panasonic HD, Sony, and older RCAs].
What doesn't make sense is it's supposed to be in everyone's hearing range until a certain age, and people describe it as a noise that makes them want to curl up into a ball and cry. A noise that makes them run across an 8 room radius just to shut off a TV that nobody was watching. A noise that makes them want to blow their brains out.

And their excuse for how people were still able to watch TV is, "well, eventually you naturally lose your ability to hear higher frequencies when you become an adult."

So they're basically implying that all kids hated watching TV because with their ability to hear higher frequencies, they can hear this suicidal sound.

Except in real life, kids watched tons and tons of TV and never said a word about this supposed noise.
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post #10 of 37 Old 04-30-2015, 04:06 AM - Thread Starter
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Originally Posted by Ratman View Post
Thank goodness we now have LCD's
Yeah, thank God for poor blacks and color shifting at different viewing angles. At least the weirdos who probably also can hear aliens talking to them don't have to put up with this alleged "whine."

And the smaller footprint, so that when your awesome new TV breaks in 2 years, you can more easily lift it and replace it, rather than buying one to last 10 and not think about moving it because it's kind of supposed to sit in your living room.
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post #11 of 37 Old 04-30-2015, 04:31 AM
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Quote:
Originally Posted by 90sTVFan View Post
What doesn't make sense is it's supposed to be in everyone's hearing range until a certain age, and people describe it as a noise that makes them want to curl up into a ball and cry. A noise that makes them run across an 8 room radius just to shut off a TV that nobody was watching. A noise that makes them want to blow their brains out.
Younger people can hear higher frequencies, there's no doubting that fact. I still clearly remember years ago, when my high school physics teacher brought a tone generator to class and proceeded to output a very high pitched sound that drove everyone nuts, but he himself couldn't hear it in the slightest. He was really having fun with that "experiment"

As for the CRT noise you describe, different people have different sensitivity to certain sounds, obviously, and not everyone reacts in the same way to the same stimuli - that's really all you need to understand.
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post #12 of 37 Old 04-30-2015, 06:28 AM - Thread Starter
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Originally Posted by tezster View Post
Younger people can hear higher frequencies, there's no doubting that fact. I still clearly remember years ago, when my high school physics teacher brought a tone generator to class and proceeded to output a very high pitched sound that drove everyone nuts, but he himself couldn't hear it in the slightest. He was really having fun with that "experiment"

As for the CRT noise you describe, different people have different sensitivity to certain sounds, obviously, and not everyone reacts in the same way to the same stimuli - that's really all you need to understand.
But the only place I've ever encountered anyone with this sensitivity is the internet. I never met a kid in my life who complained about this sound. Heck, in school they had us watching TV during class dating back to at least 2nd grade. No kid ever plugged his ears or complained of a noise. Scratch the chalkboard with your nails, though, and everyone is cringing.

Then decades later I see all kinds of people on the internet talking about how they couldn't stand to be within a 5 mile radius of any CRT because of some high-pitched noise "they all make."

Suddenly there are all these people coming out of the woodwork who apparently never watched any TV or played video games or used a computer until the advent of LCDs.
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post #13 of 37 Old 04-30-2015, 07:09 AM
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But the only place I've ever encountered anyone with this sensitivity is the internet.
And... if you read it on the internet, it must be true.
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post #14 of 37 Old 04-30-2015, 09:21 AM
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Who are these people? Just sounds like CRT bashers and like you said the advent of LCDs, pro/con stuff. Make it appear as a major con...

I'll add that some of the noise I hear in regards to flakier circuits doesn't sound that high in frequency.

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post #15 of 37 Old 04-30-2015, 09:27 AM
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Quote:
Originally Posted by tezster View Post
Younger people can hear higher frequencies, there's no doubting that fact. I still clearly remember years ago, when my high school physics teacher brought a tone generator to class and proceeded to output a very high pitched sound that drove everyone nuts, but he himself couldn't hear it in the slightest. He was really having fun with that "experiment"
that's funny. That reminds me of when people come over to my house and say "whats that beeping". Apparently the security system's been beeping for hours/days/weeks after the power blipped. Poor dog and cat.
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post #16 of 37 Old 04-30-2015, 10:39 AM
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I've been a "child" of CRT's televisions from the 50's to ~2009. Only one TV had a "whine" problem (mentioned earlier... that was a 1975 25" Zenith console).
Also, I worked in IT from 1973 to my retirement. Been around CRT monitors from monochrome green, amber and orange 3290 plasma displays... and more. The only whining I heard was not getting a long enough "break" or a pay raise.
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post #17 of 37 Old 04-30-2015, 10:46 AM
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Oh yes, on CRTs you could ALWAYS tell if a TV was on before you walked into the room, from the high pitched whine. I can still (or could ) hear it even tho I have now have tinnitus that resembles the exact same whine. During daylight with ambient noise, it is masked (the TV, not the tinnitus! ) but at night it is very prevalent (as is with tinnitus! ).

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post #18 of 37 Old 04-30-2015, 11:27 AM
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Did you "hear" it as a child? In every home that had a TV? Perhaps you had tinnitus as a child and blamed it on the TV. Or... maybe the CRT caused the tinnitus.

If this were a "major" audible concern, I would think that it would have been addressed 60 years ago. Again... if a CRT "whines", there's a problem with the electronics, not the technology.
(Or... you have the contrast turned up to maximum)
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post #19 of 37 Old 04-30-2015, 11:36 AM
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Quote:
Originally Posted by 90sTVFan View Post
This makes no sense to me, as based on the way people have described the noise (people talk about how they wanted to run out of the room crying when they heard the noise, or how it would give them major headaches), if most kids were able to hear it, no kids would ever have watched TV back in the days when CRTs were ubiquitous. But we know that's not the case, as most kids watched tons of TV (not to mention played tons of video games). Personally, I don't remember ever hearing this noise, and I started watching hours upon hours of TV from a very young age. And I wasn't a kid who listened to things with the volume turned up, either. I had the TV on a pretty low volume and I never listened to blaring music. My hearing tests were always fine.

Is it just the rare person who is born with exceptional hearing who can hear that frequency?
I could hear it till I was in the 30s.. as a kid I know the tv was on downstairs when I was in bed, I could hear the hiss/buzz.. Of course now at 50 I hear the constant Tinnitus buzz from all the loud music and air tools in the shop when I was younger.. and my tinnitus (everyone's can be different) sounds like the old 19" BW TV!

To answer the previous posters question yes I could hear other peoples TV as well.. It would stop when the TV was shut off. They also had sonar at a couple of traffic lights ( to alter when the light changed if no trafic) back in the late 70s and that really hurt my ears.. mom could not hear that either..

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Last edited by airscapes; 04-30-2015 at 11:41 AM.
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post #20 of 37 Old 05-03-2015, 12:47 AM
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The frequency of the flyback is approximately 15.625KHz or 15.734KHz (depending on the horizontal sweep frequency that differs between PAL and NTSC):

https://en.wikipedia.org/wiki/Flyback_transformer

This is high enough in frequency as to be on the border of audibility for the average adult, but plainly audible to the average child or even teen.

Here, test yourself with this ringtone:


I cannot hear the 12KHz or above. My son installed the mosquito ring tone on his phone and when I realized I could not hear it (surprising to me) I tested my hearing with my home theater and discovered a brick wall at 12KHz.

When I was a teen I could plainly hear the flyback in any NTSC television. Of course, back then flyback transformers were not so good and made lots of noise, but I could detect significant variation in loudness between quality televisions and the el cheapo models my parents bought. I could also hear the flyback break up into harmonic-intermodulated chaos when the horizontal sync was lost.

I could hear the flyback from all the way on the other end of the house and through the floor. It made sleeping difficult until I learned to just ignore it eventually, or maybe until my hearing started to fade from practicing with garage bands.

In contrast, my parents could not hear the flyback at all after age 45 or so and did not believe that it was keeping me awake.

Fast forward to ten years ago and my teenage son and daughter awkwardly thanked me for the gifts of old CRT supertubes from local Freecycle. After installing them in their bedrooms and noting that they would not use them despite having a third supertube in the living room, I asked why.

Turns out the flybacks were annoyingly loud. I could not even hear them.

My daughter indicated that, like younger me, she could plainly hear the flyback from all the way on the other end of the house and through the floor. It was keeping her awake at night. With an old tube set in her bedroom the noise was intolerable.

I changed her TV out for another old tube that she claimed had less noise and she actually used it a few times before heading off to college.

So in short, yes the things can be annoyingly loud to a young person and no they do not have to be on the verge of failing to get that loud. They only have to be audio transducers. Think about it... transformer... deflection coil... magnetic field... old shellac... metal cage... there are at least two possible sources of horizontal sweep noise in any CRT TV, the flyback and the horizontal deflection coil. Either one can maybe function as a sort of speaker.
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post #21 of 37 Old 05-03-2015, 08:49 AM
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Sounds like another case of genetic Tinnitus. Like the point the OP is trying to get across, if everyone had the problem then we all would have gone nuts from it when we were CRT kids.

Breakdown of transformer and toroid laminates can also cause mechanical vibration moding down at much lower frequencies.

On that ringtone test, one should make sure the audio system they're using is capable of reproducing those frequencies, and watch for excessive roll-off. PC audio/speakers and cellphones, uh I dunno...

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post #22 of 37 Old 05-27-2015, 06:17 AM
 
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I heard it as a kid, it didn't bother me. I've been very anal about protecting my ears and as an adult I can still hear it; still doesn't bother me.

As a kid, I could even tell which channel a TV was tuned to by the frequency of the sound the CRT emitted. Sounds weird, but the higher channels sounded different from the lower ones. And it was plain as day when a scrambled channel was on, because the CRT would make all sorts of funny high pitch sounds when it tried to scan that wavy signal.

These kids you speak of are just a little over sensitive, I think. They're probably allergic to peanuts and strangers too. I wouldn't be surprised if they complained about the buzzing on a plasma, if it's new to a kid and mildly unpleasant it's going to come across as the end of the world
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post #23 of 37 Old 05-28-2015, 11:29 PM
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I'm 29, and I can still hear 19k in one ear and 18k in the other,.

My tube amp (electric guitar) picked up the 15khz whine from the neighbors CRT through the thick concrete wall.
Took me several day to actually figure out that it was not an oscillation from the amp itself.

Music is still a pleasure, though some times I hear a microphonic squeal on some records that the sound engineer did not hear.
128kbps MP3s actually completely missing frequency above 16khz, not that there is much music there.
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post #24 of 37 Old 05-28-2015, 11:56 PM
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Quote:
Originally Posted by CherylJosie View Post
The frequency of the flyback is approximately 15.625KHz or 15.734KHz (depending on the horizontal sweep frequency that differs between PAL and NTSC):

https://en.wikipedia.org/wiki/Flyback_transformer

This is high enough in frequency as to be on the border of audibility for the average adult, but plainly audible to the average child or even teen.

Here, test yourself with this ringtone:

https://www.youtube.com/watch?v=IrewnzQYrPI

I cannot hear the 12KHz or above. My son installed the mosquito ring tone on his phone and when I realized I could not hear it (surprising to me) I tested my hearing with my home theater and discovered a brick wall at 12KHz.

When I was a teen I could plainly hear the flyback in any NTSC television. Of course, back then flyback transformers were not so good and made lots of noise, but I could detect significant variation in loudness between quality televisions and the el cheapo models my parents bought. I could also hear the flyback break up into harmonic-intermodulated chaos when the horizontal sync was lost.

I could hear the flyback from all the way on the other end of the house and through the floor. It made sleeping difficult until I learned to just ignore it eventually, or maybe until my hearing started to fade from practicing with garage bands.

In contrast, my parents could not hear the flyback at all after age 45 or so and did not believe that it was keeping me awake.

Fast forward to ten years ago and my teenage son and daughter awkwardly thanked me for the gifts of old CRT supertubes from local Freecycle. After installing them in their bedrooms and noting that they would not use them despite having a third supertube in the living room, I asked why.

Turns out the flybacks were annoyingly loud. I could not even hear them.

My daughter indicated that, like younger me, she could plainly hear the flyback from all the way on the other end of the house and through the floor. It was keeping her awake at night. With an old tube set in her bedroom the noise was intolerable.

I changed her TV out for another old tube that she claimed had less noise and she actually used it a few times before heading off to college.

So in short, yes the things can be annoyingly loud to a young person and no they do not have to be on the verge of failing to get that loud. They only have to be audio transducers. Think about it... transformer... deflection coil... magnetic field... old shellac... metal cage... there are at least two possible sources of horizontal sweep noise in any CRT TV, the flyback and the horizontal deflection coil. Either one can maybe function as a sort of speaker.
Interesting test. I'm 38 and got to about 15500 before it became silent, better than I thought. I guess this means it doesn't matter a shred whether my speakers can play up to or more than 20 000khz.
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post #25 of 37 Old 05-29-2015, 11:38 AM
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Originally Posted by Sean Spamilton View Post
Interesting test. I'm 38 and got to about 15500 before it became silent, better than I thought. I guess this means it doesn't matter a shred whether my speakers can play up to or more than 20 000khz.
It does not matter to you whether your speakers can play up to or more than 20 000Hz (ftfy) but it very well might matter to others in your household, particularly your wife and children (and your little dog too, mwa hah hah).

It might also matter whether your amplifier can accurately reproduce much higher frequencies. Intermodulation distortion can certainly translate ultrasonic content of hi-res recordings into baseband energy that is harmonically unrelated to anything in the program. Such thing would be bad... and is a very good reason why hi-res recording should be pre-emptively filtered for any ultrasonic content somewhere in the signal path before it reaches the power amp.
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Last edited by CherylJosie; 05-29-2015 at 11:40 AM. Reason: 20 000khz is way high frequency
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post #26 of 37 Old 11-13-2015, 06:06 AM
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As a kid I had good hearing (I still do for my age and demographic - Walkman/mp3 generation), and I don't remember CRT circuitry ever making noise. As others have said, if it were so noisy, kids would not have watched. I hated the whine of fluorescent lights, for instance
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post #27 of 37 Old 11-13-2015, 08:27 AM
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Quote:
Originally Posted by Squirrel! View Post
Oh yes, on CRTs you could ALWAYS tell if a TV was on before you walked into the room, from the high pitched whine. I can still (or could ) hear it even tho I have now have tinnitus that resembles the exact same whine. During daylight with ambient noise, it is masked (the TV, not the tinnitus! ) but at night it is very prevalent (as is with tinnitus! ).
Same here. As a child, I always knew if one of the TVs were on before I actually saw it. If I went into a store, I could sometimes hear the whine of a (out of sight) monitor, indicating security camera(s) in use.

Once when my daughter was young, I came back to her room after putting her to bed. I looked around upon hearing that whine. She had quickly turned her (CRT) TV's brightness down to 0 in an attempt to fool me. Informed her I invented that trick.

Used to pull that on our mom who never had a clue, bless her heart. And the RF whine/hum has never been painful or annoying.
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post #28 of 37 Old 11-13-2015, 02:35 PM
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Originally Posted by FireDragon76 View Post
As a kid I had good hearing (I still do for my age and demographic - Walkman/mp3 generation), and I don't remember CRT circuitry ever making noise. As others have said, if it were so noisy, kids would not have watched. I hated the whine of fluorescent lights, for instance
As others have said, it's "poorly functioning" units that were usually the culprit of offensive levels of noise. Also a display with no input signal could produce a big whine - but this was not common in the house, since the static snow doesn't produce the same effect...

I very clearly remember during a college final exam held in a large lecture hall that the CRT projector overhead was making a very annoying screech that bugged the hell out of me (there was nothing being projected). I asked the prof if he could please find the switch to turn it off, and he, of course, couldn't hear it at all... Neither could many people around me. I knew my hearing was quite good in those days, and I was very bummed to take the "hearing age" tests and finding that I was right on schedule for loss of high frequencies.

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post #29 of 37 Old 11-14-2015, 03:57 AM
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Quote:
Originally Posted by CherylJosie View Post
The frequency of the flyback is approximately 15.625KHz or 15.734KHz (depending on the horizontal sweep frequency that differs between PAL and NTSC):

https://en.wikipedia.org/wiki/Flyback_transformer

This is high enough in frequency as to be on the border of audibility for the average adult, but plainly audible to the average child or even teen.

Here, test yourself with this ringtone:

https://www.youtube.com/watch?v=IrewnzQYrPI
Despite some occasional ringing in one ear, I can hear all the tones.
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post #30 of 37 Old 11-14-2015, 06:35 AM
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I still hear the CRT whine. Its not highly objectionable or anything, just a little bit annoying sometimes (primarily when the tv is muted)
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