Blackmagic Forum

Development suggestion: add "average dB" option, as a NUMERIC value, in addition to "peak dB", in the Meter plugin used in FL. The focus in balancing dialog levels is average dB, but now it's "rule of thumb ... guess the "average based on peak dB"... the same metric as used in Auto-Normalize

You mean you would like the Meter plug-in to be an RMS device. Yes, it's a shame that you can't choose between Peak and RMS.
If you want a metering plug-in that shows average levels you might like this one.
https://youlean.co/youlean-loudness-meter/

According to the User Reference, Fairlight channel and bus meters are RMS weighted.

True, but he's referring to the meter plug-in.

Peter Cave wrote:According to the User Reference, Fairlight channel and bus meters are RMS weighted.

Do you deduce it from this sentence? "All of these track and bus meters (with the exception of the Loudness meters) display both peak and RMS (root mean square) levels against a dB scale." (page 3144)

I'm not sure that means it will function as an RMS meter. Rather some sum of sample peaks and RMS. I use the Waves Dorrough for RMS metering and it shows a different result than the track and bus meters in DaVinci.

Vit Reiter wrote:sum of sample peaks and RMS.

It says "peaks and RMS", so I interpret that to mean RMS metering with Peak Hold marks. And I do see Peak Holds.

Vit Reiter wrote:I use the Waves Dorrough for RMS metering and it shows a different result than the track and bus meters in DaVinci.

In some DAWs you'll see a different result because the channel meters are post panning whereas inserts are pre-. So a signal that goes from a mono track into a stereo bus would potentially read differently depending on where metering is done.

How large is the difference you see?

To reiterate: a NUMERIC display, e.g., avg = -12dB, as distinct from peak, which Meter plugin now shows. Ideally, show both numeric values, otherwise, option selection for the value sought.

Mattias Murhagen wrote:

Vit Reiter wrote:I use the Waves Dorrough for RMS metering and it shows a different result than the track and bus meters in DaVinci.

In some DAWs you'll see a different result because the channel meters are post panning whereas inserts are pre-. So a signal that goes from a mono track into a stereo bus would potentially read differently depending on where metering is done.

How large is the difference you see?

Both meter are at the end of chain. (Main 1 bus)
See figure.

Come to think of it; do the Dorrough meters actually use RMS?

Mattias Murhagen wrote:Come to think of it; do the Dorrough meters actually use RMS?

No. They use their own meter ballistics model to display average level.

Mattias Murhagen wrote:Come to think of it; do the Dorrough meters actually use RMS?

Reading a Dorrough Meter:

A Dorrough Loudness Monitor is roughly analogous to a "PPM" and a "VU" combined, but with more complimentary ballistics assigned to each parameter. The result is an established relationship between the PEAK and the RMS content... This is defined as RELATIVE LOUDNESS...

"Mike Dorrough"


Dorrough meters ballistics include a weighted type of VU meter and also show details about the peak levels. This allows you to monitor both RMS and peaks quickly and efficiently using a single meter.

"David Silverstein"


My view is that the VU meter (average loudness, etc.) is quite close to the RMS value and in fact I need it more than true-RMS. Track and Bus meters in DaVinci I see more as Sample peak meters, which do not provide me with information about the perceived loudness. That's not bad, they just show something else. Dorrough meters are closer to DaVinci Loudness meters, which in turn are great for checking all content.

But maybe I'm not right, audio metering is quite a jungle. I like Dorrough meters and I achieve the desired results with them and none of my clients have any problems.

Vit Reiter wrote:Reading a Dorrough Meter:

A Dorrough Loudness Monitor is roughly analogous to a "PPM" and a "VU" combined, but with more complimentary ballistics assigned to each parameter. The result is an established relationship between the PEAK and the RMS content... This is defined as RELATIVE LOUDNESS...

"Mike Dorrough"


Dorrough meters ballistics include a weighted type of VU meter and also show details about the peak levels. This allows you to monitor both RMS and peaks quickly and efficiently using a single meter.

"David Silverstein"


My view is that the VU meter (average loudness, etc.) is quite close to the RMS value and in fact I need it more than true-RMS. Track and Bus meters in DaVinci I see more as Sample peak meters, which do not provide me with information about the perceived loudness. That's not bad, they just show something else. Dorrough meters are closer to DaVinci Loudness meters, which in turn are great for checking all content.

But maybe I'm not right, audio metering is quite a jungle. I like Dorrough meters and I achieve the desired results with them and none of my clients have any problems.

Well you can't expect a meter that is "close to the RMS" and one that is RMS to show the same thing. You should expect the opposite. Not saying that Dorroughs aren't great, I think they are and I used to use them years ago, but I just don't really see a reason to expect them to show the same as the channel/bus meters then.

The only other thing I can think of that could (?) be an issue is various delays between the plugin and channel meters and when they show signal. It's perhaps possible that you get a different reading at a given moment in time because the meters are showing slightly different times of measurement (since one is a plugin and the other isn't). At the very least it'll by definition take a tiny amount of time for audio to go from plugin to the channel meter.

I would recommend that instead of looking at the meters using regular real-world audio you instead pick a sine wave of a known level. That will provide a steady-state tone that doesn't change over time and it's much easier to see what the actual difference is.

Oh and last thing, there's a couple of ways of measuring RMS where one is referencing a square wave and one is not. The latter is the AES standard I think. The former results in a lower value for sine waves and other content. I think I got that right. At any rate it explains why sometimes even sine waves measure differently. And so taking this into account with the rest of I what wrote it's possible that it's entirely reasonable for the meters to be off quite a bit.