I vaguely remember (I think) seeing a commercial about this:
There was a setting on the TV that would keep the volume the same no matter what was going on in the TV. So whether it was an explosion, or two people having a conversation, the volume would remain constant.
Does anybody remember anything like that? "Cuz I want a TV that does that. 
TVs have this, but they may use a trade name that’s not intuitive. Samsung has Auto Volume for example. Having external audio may change this. YMMV whether it’s worth it or it creates more drawbacks than it’s worth.
It’s called “automatic gain control.” Some TVs called it “automatic volume control” and others gave it the counterintuitive label “loudness.”
There are a bunch of reasons why its effectiveness is limited. You can try the audio settings on your TV, where it’s probably mixed in with an audio equalizer, or you can go all out and order this.
I seem to remember this was a major selling point for Magnavox back in the 90’s. Very heavily advertised.
That’s probably the commercial I was thinking of.
You want some level of dynamic range in your audio, or it won’t sound right. And how quickly do you need it to react?
My dad’s TV needs this. He’s had a 2018 model 60 inch HDTV in his living room but whenever I’m over to watch a movie he has to have his sound bars control in his hands at all times because audio and loud sound effects are significantly different, he turns up to hear dialog but then has to immediate turn down the sound when any action happens. Only happens on his TV too despite me having the same TV manufacturer and sound bar.
I hope it was advertised by a shouty man.
I have a 9 year old VIZIO that is supposed to have this. Supposed to keep commercials from blasting your ears.
It sort of works, but as far as I can tell, It has to be set/turned on every time you shut down the TV. I gave up on it.
One of my receivers had this feature. Dynamic Range Control, or something like that. IIRC, it was explained as a way to keep really loud, unexpected parts of movies (like explosions or car crashes) a bit quieter so as not to wake up everyone in the house. IIRC, it didn’t work all that well as it had a tendency to make everything sound wonky.
That sounds like a classic example of what happens when your surround sound settings are wrong.
If you set up your surround sound thinks you have a center speaker but you don’t have one, or you have the center speaker volume turned down way too low (by accident or otherwise), the dialogue will be really quiet. In surround sound, the majority of the dialogue is pushed through the center speaker, with a little bit of it coming from the front speakers. The the center speaker isn’t there (or it’s turned down), you’ll only hear what comes from the front speakers and you’ll turn it way up so you can actually hear it. Then you’ll get blasted by the noise as soon as anything remotely loud happens.
If all you’re using is the TV speakers, check the surround sound settings. In fact, look at what your TV is set to, and change his to the same thing. It’s probably some preset virtual surround sound that’s set to the wrong thing and probably needs to go back to ‘normal’ or ‘TV’ or something like that.
If he actually has at least three speakers (center and L/R front), you’ll have to A)make sure whatever is mixing the surround sound knows he has a center speaker and B)try turning up the volume on it. If that doesn’t work, make sure it’s plugged in. I’ve spent far too much time chasing down sound quality issues just to find out a wire came loose.
Whenever I hear something like that, it reminds me of an old Eric Idle or John Cleese interview about The Flying Circus. The plan was to slowly turn down the volume over the course of the show so that people would keep turning UP the volume on their sets. Then, towards the end, do something really loud. Their equivalent of the FCC nixed the idea.
My Panasonic TV calls it “A.I. Sound”, and describes it as “Equalizes overall volume levels across all channels and external inputs”
IIRC, there are several numbered levels that you can apply for it in the menu, that range from basically being “keeps commercials from totally blaring”, to “really damps out volume fluctuations, even within a TV show”.
Do people still call them TV “sets”?
Isn’t this the same as a compressor and/or limiter? If so, there are definitely settings to mess with until it sounds right: amount of compression, knee shape, attack/release time, gain, threshold…
ETA: maybe a sufficiently “A.I.” filter can automagically figure out good settings that will probably sound OK, with the push of a button.
ETA 2: I would expect stuff like obnoxious commercials to be already heavily compressed
You wouldn’t need an AI to figure out good settings. You have humans at the factory figure out using human intelligence what sounds good, and then they package that as the standard settings.
The same people that seem to think that soap opera effect/motion smoothing should be defaulted to on? How many people returned their brand new TV’s because of that one? I know the first time I encountered it, it was probably a week or so before I figured out why a brand new TV seemed to have awful video quality. I was on the brink of bringing it back before I read about the setting and turned it off.
The people at the factory can certainly come up with the baseline, but an AI engine could tweak settings on the fly to the preferences of an individual user (or household). Maybe you turn your TV down during commercials, but I don’t. Maybe I turn my down during action scenes in movies while you turn your volume up so you can hear the dialogue over other noise. Whatever the case AI can work that out and start making the adjustments for you.
Whether or not it’ll work well or that people will like it is a different story.
That seems to be one of those things that either bug the shit out of you or you don’t even notice. I was at my brother-and-sister-in-law’s house over the summer, and they were playing some TV series for me I hadn’t seen before (I can’t remember which one). I was wondering what in the hell was with the weird choice of cameras or cinematography, and went to my phone to look up the show and see if anybody else commented on it, but nobody did. Then it dawned on me that some TVs have this interpolated mode or whatnot that smooths out action, and I found it buried in the menu. They had no idea what weird artifacting I was seeing, where to me it was so obvious and distracting. At any rate, they just turned it back to the “soap opera” mode after I finished watching the show, so, clearly, a lot of people seem not to notice, care, or even prefer it for some odd reason.
My cable box has a feature sort of like what the OP describes. The setting is called Audio, and the choices are Narrow, Default, and Wide. The description on one of them (I think Narrow) says voices will be louder, the other (Wide?) has sound effects louder, and then of course Default is what the broadcast is actually sending.
I was imagining the A.I. would have been trained on a baseline of what sounds good to the average viewer, and can examine the current program (too loud, too soft, temporal characteristics, frequency characteristics, dynamic range, is it a commercial) and cleverly adjust the audio settings. No idea how well it would work in practice. Otherwise, I would hope some reasonable defaults would be in place, but one could still adjust the half-a-dozen knobs individually-- if you can’t, and you don’t like the presets for whatever reason, the feature becomes useless.
As I recall, the Magnavox spokesman was John Cleese, and it featured a car salesman or the like shouting on the TV. He kept shouting louder and louder as the volume decreased, and Cleese says to him, “It’s no good, old man!”