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Subject: Calm
Posted by: UKharrie
Date: 11/9/2015 7:31:33 PM

In Europe there is a similar techno change called EBU R128 - this is a significant change to setting audio levels; not by measuring peaks but by using the perception of levels, which vary with frequency and other sounds present.
I wonder what Sony is going to do to address these Standards which for National Broadcasters "should" fix the variations between programmes / channels / and advertisements, which most folks find rather annoying?

At present SFS and SMS use bar-meters which I presume are peak-reading and whilst it remains essential to avoid reaching 0dB other forms of meter are often reading some delayed peak, so they behave more like an analogue ( moving coil ) meter to give something nearer to an average level - being far easier to set power amplifiers driving a Public Hall, for example.

I suspect it wont be very easy, since the Standard may require the finished audio files to be tested against .... and here I can't determine exactly "what"

Message last edited on 11/9/2015 7:37:44 PM by UKharrie.
Subject: RE: Calm
Reply by: pwppch
Date: 11/9/2015 10:22:49 PM

Subject: RE: Calm
Reply by: Geoff_Wood
Date: 11/10/2015 6:24:41 PM

SF Pro has configurable meter 'ballistics' (PPM, VU) .

But isn't CALM and EBU128 a bit more complicated, like an average of the whole file, or a section averaged over a significant time ?


Subject: RE: Calm
Reply by: rraud
Date: 11/11/2015 8:18:26 AM

The meter in SF11 (and VP) can be analyze the entire timeline w/o running it in real-time.. it will not change the levels for you though. There is a low cost plug-in available that can do this for the 'audio challenged'. I can't recall the name or URL at the moment

Subject: RE: Calm
Reply by: UKharrie
Date: 11/14/2015 6:24:41 PM

Thanks SonyPCH - I am working my way through that article - it's very instructive, although I was down to Fig2 before I realised he was discussing Fig1 and not the large Meters in Fig3. That screenshot of SF - Those meters don't show and I'm watching on a 40" TV. Fig 3 is to the side and that took my glances.

BTW I did a "search" for CALM Act in this Forum and got nothing, so now it's there for all to see.
+ I'm just wondering how this translates for Studio Movie editing - there isn't any consensus on the normal level, ( and it's always jumping about, as it were.). Personally I try for -12dB although there is a temptation to raise it to -9dB . . . It would help if there was a "green marker" at -12dB level, so folks aren't making their stuff too loud ( as so often with a well known Video-all-comers-Channel ). - Even though any basic Editor may use "Legacy Peak Metering". It's a lot better than nothing, since we don't have Client-pressures to contend with.

I understand one serious issue in the past was that peaks could occur outside the "samples" - so a "Legacy Peak Meter" could be lying unintentionally. This appears to have been resolved in SFP incorporating CALM metering, where a different approach is incorporated, etc.
However, I'm not sure it can be done in "Real-Time" since that would require an Infinity of Samples ( but one might be satisfied with a 200kHz upper limit since no transducer ( Yet? ) can reproduce that.).

However, with Processors into GHz - maybe it can be done.

Message last edited on 11/14/2015 6:29:01 PM by UKharrie.

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