Please explain the master meter

[aholub]

Could someone please explain the master meter to me? There are two scales, and the outer one is lower. Also, what's the meaning of the green boxes on the outer scale (going from 0 to +4 on the attached picture). Is there any way to see an *average* level over some time interval that I set?

Thanks!

[LightOfDay]

the 2 inner bars meter the peaks, the outer 2 bars meter the RMS value.

[clepsydrae]

Right-click on the master meter and you will see a variety of options there.

The "green box" you refer to is the "red threshold" for the RMS meter -- it's the range that is "above zero" on the RMS scale but, since that is less critical in the RMS meter when there is a display offset in effect (which is the default) the "red threshold" lets you set a range that is sort of the "caution zone", as far as I interpret things. The location of that zone will shift around if you change the display offset.

You can adjust the window size in that same dialog window to control what the average level is representing.

I was going to say "read the manual" but it appears that none of this is in the manual. :-)

[Aesis]

Originally Posted by aholub

Could someone please explain the master meter to me? There are two scales, and the outer one is lower. Also, what's the meaning of the green boxes on the outer scale (going from 0 to +4 on the attached picture). Is there any way to see an *average* level over some time interval that I set?

Thanks!

The green boxes are sort of a loudness target, that varies based on how you calibrate the RMS meter. There was a thread about this recently and I laid out exactly at what RMS they sit on every different calibration, but can't recall at the moment.

You can calibrate the RMS meter by right clicking.

[Masi]

Originally Posted by clepsydrae

I was going to say "read the manual" but it appears that none of this is in the manual. :-)

Yes, it isn't in the manual.

I think I get what the display offset (sets RMS 0dB to a value of dBFS on the meter) and the red thresholds (adds a "safety margin" area to the RMS above 0dB before the meter turns red) does. But I'm unsure about the display gain. Does it add some gain to the signal before calculating the RMS?

Masi

[clepsydrae]

Originally Posted by Masi

I think I get what the display offset (sets RMS 0dB to a value of dBFS on the meter) and the red thresholds (adds a "safety margin" area to the RMS above 0dB before the meter turns red) does. But I'm unsure about the display gain. Does it add some gain to the signal before calculating the RMS?

Yeah.

These are all just display configurations, as I think you already understand.

Display offset shifts how the numerical scale of the RMS meter is displayed against the bouncing level indicator.

Display gain adds (or subtracts) a small amount from the bouncing level itself. Like a golf handicap. :-) (Under the hood, I doubt it actually applies gain to the signal, but it doesn't matter since we're just talking display here.)

Red threshold just determines the level at which the bouncing level will turn red. The higher this value, the more room before the bouncing level looks red and scary.

Note that you can manually enter arbitrary values for all of these settings.

[Masi]

Originally Posted by clepsydrae

Display offset shifts how the numerical scale of the RMS meter is displayed against the bouncing level indicator.

Note that my own explanation "sets RMS 0dB to a value of dBFS on the meter" seems to be quite accurate. Best example is 12dB: one might wonder why the topmost number reads 6 and not 12 until you see that RMS 0dB is now at -12dBFS.

Originally Posted by clepsydrae

Display gain adds (or subtracts) a small amount from the bouncing level itself. Like a golf handicap. :-)

You mean like adding 3dB just to be extra sure not to mix too loud? Not quite sure why I would need that given I have already the display offset.

I tried to set the red threshold to a negative value, but that only got me a dark red reading (background) from 0dB upwards (why?) instead of a bright red reading (foreground) below 0dB.

Masi

[clepsydrae]

Originally Posted by Masi

You mean like adding 3dB just to be extra sure not to mix too loud? Not quite sure why I would need that given I have already the display offset.

It's just there so you can adjust how the bouncing green level indicator relates to the peak indicator. Some people like it to sit at around the same level.

Since RMS is a relatively arbitrary way to indicate average level over time, different people are going to have different opinions about where it should be displayed in relation to the peak indicator. And it will change depending on the audio, too. These settings just let you move both the level indicator and the graticule around to suit your preferences.

I tried to set the red threshold to a negative value, but that only got me a dark red reading (background) from 0dB upwards (why?) instead of a bright red reading (foreground) below 0dB.

Can you post a licecap of what you're seeing? I'm not understanding your description (dark red vs bright red?)

But I do see weirdness with negative red threshold values as well: I set it to -6, and it appears to effectively get set to just under 0dB instead. Pulling the dialog window back up, it shows -5.9 or some similar close-but-not-quite value. Might be a bug. But it seems unlikely that anyone would want to set a negative value for it.

[Masi]

Originally Posted by clepsydrae

But I do see weirdness with negative red threshold values as well

That's what I have been trying to say. Actually it doesn't seem to make a difference if you set it to -1 or -6. The funny things start to happen once the value is negative.

My idea for using a negative value was to force an RMS indicator bar in red below the 0dB marker.

[alanofoz]

Originally Posted by Masi

My idea for using a negative value was to force an RMS indicator bar in red below the 0dB marker.

Reminds me of those who set their bedside clocks 10 min early...

Makes sense to some, makes no sense to me

[Masi]

Originally Posted by alanofoz

Reminds me of those who set their bedside clocks 10 min early...

Nice analogy.

You shouldn't have told me that I can enter any value I like

[Masi]

Here's a draft for an addition to the manual. Unfortunately I don't know how much the windows size affects RMS and more specifically when to choose a longer or shorter setting.

Anyway, here we go:

RMS metering settings

* windows size

Determines the number of milliseconds used to calculate the RMS from. The longer the more ... ????

* display offset

Adjusts the 0dB marker of the RMS meter in relation to the peaker meter, ie. a 14dB offset means that 0dB RMS equals -14dB peak.

* display gain

A fixed gain added to the actual RMS value in the display. Use it to adjust the RMS value in relation to the peak value. +3dB will get you on average roughly the same reading for RMS as for peak.

* red threshold

The RMS indicator bar will normally turn red above 0dB. You may choose a different threshold in case you're fine with a few dBs above zero.