[Nition]

You'll usually stop hearing the CRT whine in your 20s, 30s if you're lucky. It's at nearly 16KHz and the highest frequency you can hear always drops as you age.

Of course, these days people also regularly don't hear it since CRTs are nearly all gone.

[antod]

Even back in my youth and early adulthood, there was a wide variation on how loud CRTs were between models and individual units. There were some that were close to silent for me, while others were very noticeable.

[ikari_pl]

37 here. Definitely still hear if the CRT is on. I have a few 8bits.