Normalise sound volume somehow? (1 Viewer)

[RobNorthcott]

Recently more and more programmes (usually films and music programmes such as Jools Holland) are being broadcast with what I assume to be some sort of high dynamic range sound so they appear much quieter than other stuff.

Is there any information in the broadcast stream that could be used to identify this and automatically alter the volume? In my head it would be a bit like the auto refresh rate feature, with a volume setting for "normal" sound and another one for "high dynamic range" sound (if that is even a thing).

Do any of the resident experts know if this is possible to do?

 

[CyberSimian]

Recently more and more programmes (usually films and music programmes such as Jools Holland) are being broadcast with what I assume to be some sort of high dynamic range sound so they appear much quieter than other stuff.

I don't know about Jools Holland, but many major feature films and prestige drama productions are broadcast on DVB-T2 with multi-channel sound (where "multi" means "more than two"). I am not sure whether this is what you are hearing.

The problem with multi-channel sound occurs when you play them through a stereo loudspeaker setup without an appropriate "mix down" from multi-channel to two-channel. I cannot now remember what the MP default is, but I have mine setup like this (see items in red box):



If mix-down to stereo is not enabled, I find that speech is significantly quieter relative to the music and sound effects, compared to normal stereo broadcasts. An "equal" balance would probably be "0.7+0.7" (for some reason the mathematician in me says that the sum of the squares should add to one). My settings "0.8+0.6" give more emphasis to the center channel (but the sum of the squares still adds to one). You set these values in "MP Config" in the "Audio Decoder" settings in the "Codecs" section.

MP is a bit lax in its display of the multi-channel sound property. If you are watching live TV that has multi-channel sound, or recorded TV that has multi-channel sound, MP will not display the icon for it on the "Info" pop-up. If you are watching a video (e.g. recorded TV) that has multi-channel sound, MP can display the multi-channel logo, but usually doesn't. This is because it displays the property for the start of the recording, which (with pre-padding) is usually the programme preceding the film or drama production that has the multi-channel sound.

The only reliable way to tell if a programme has multi-channel sound is to look at your TV's "Info" display when the programme is broadcast -- that will (probably) indicate the type of sound being received (stereo or multi-channel). My Sony TV does this.

-- from CyberSimian in the UK

 

[RobNorthcott]

Thanks for the reply @CyberSimian . That's another thing to consider - I had assumed that it was because of less compression on the sound to get better dynamic range, whereas most broadcast sound is heavily compressed. (By compression I mean dynamic compression rather than file compression of course), but that is certainly another possibility.

 

[CyberSimian]

I had assumed that it was because of less compression on the sound to get better dynamic range

That could well be what you are hearing.

If you want less dynamic range (i.e. more compression), there is another setting that may work: "Dynamic Range Compression" on the "Audio Settings" tab (to the left of the "Mixing" tab that I showed in the screen shot in my previous post). I have never used it, so I don't know what effect it has.

-- from CyberSimian in the UK

 

[RobNorthcott]

If you want less dynamic range (i.e. more compression), there is another setting that may work: "Dynamic Range Compression" on the "Audio Settings" tab

Thanks... but more compression is the last thing I want for music programmes. It's not really a big deal to turn up the telly volume - just wondered if there may be some cool way of automating it.

 

[joecrow]

Just wanted to add that I have experienced a similar reduction in sound volume on my 5.1 sound setup with the German TV sender ZDF. The Live TV on ZDF DVBT2 is normally in Dolby both regular TV programs (native multichannel) and older programs (up mixed from stereo) sound fine but some movies with original multichannel sound tracks will play very quietly. Not sure what is happening but sometimes "if" an alternative audio track is available it will be louder but not always.