MLoudnessAnalyzer - setting Offset

[DarkStar]

While looking into this thread: http://www.kvraudio.com/forum/viewtopic ... 8&t=460241 I wanted to work out how to use the Offset setting.

I tried MLoudnessAnalyzer (MLA) with the EBU 3341 Test signal:

Stereo sine wave, 1000 Hz, −23.0 dBFS (per-channel peak level);
signal applied in phase to both channels simultaneous; 20 s duration

and the LU meters showed 0, without any Offset needed, on any of the 3 selectable EBU scales. (NB The frequency is important; other frequencies will be registered at other LU levels)

That confirms the calibration and reference level for MLA. The PDF User Guide has more info (go and read it now). Here's a screenshot showing the audio going into MLA, the LU meters registering 0 and the audio signal level at -23 dbFS:

>>> http://i.imgur.com/Seu2YVJ.png

Adjusting Offset 'just' changes the levels seen on the meters (and in the figures). So, if you want a -18 reference level ("Target"), you would set the Offset to -5. A -23dbFS audio signal would then register at -5 on the LU meters, a -18dbFS audio signal would register at 0 on the meters and so on. As can be seen in these two screenshots:

. . . . . . . . . . .

http://i.imgur.com/DNYlbai.png . . . . . . . . http://i.imgur.com/1xIsAnk.png

Where the confusion can arise is that the actual reference level is not directly shown on the GUI - it is in fact -23 +/- the Offset. This leads to the changes suggested in the other thread:

• (a) Show / adjust the reference level ("Target") explicitly, the default would be -23dbFS (= 0 LU) and there is no need for the Offset,
  (b) add "LU" to the figures as a gentle reminder
  (c) perhaps add in a a GUI control and graphics in the meters and timegraph for the Short-Term maximum level.

[masitito]

Seems all your requests have been granted. Too bad only that the guys at Melda forgot to update the manual. I had to stumble on your post to verify my assumptions about the different settings.

The different EBU modes seem to define the allowed headroom in comparison to the target level. The new "limit" seems to implement your request (c) both above and below the target (and all levels not just short-term).

What I didn't figure out though was how to use offset to get a K-metering working with the plugin. OTOH I probably don't need it if I don't know by now

Masi

PS: And I don't know on what timeframe LRA operates. Is it the short-term level?