Loudness metering in recording.

[Tom Conen]

In a recent topic I had an argument about the necessity of VU-Meters.

This brought me to some questions:

- Do you use VU-Meters to check the average level of your recording?

- What other meters do you use? - analog, digital, hardware, software, etc.

- What's your experience regarding loudness consistency of your tracks using these meters?

- What do you think how accurate these meters are?

Until now I was happy with the VU-Meter of my 788T and a software dorrough meter. Recently I played around with Ozone5 and I love its metering options. (including VU, LUFS, K-Metering, and a spectacular 3d spectrogram)

And BTW:

I think it's time to introduce myself:

[VM]

Until now in post production, i liked to control the average level on a Vu meter. Now i use a Lu meter (TC electronics) AND a peak meter.

When I'm recording I like peak meters to check the peak : checking the level with only a Vu meter seems awfull (and dangerous) to me. I like double mode Vu+peak we can find on SD's devices.

The best loudness meter i know... is my 2 ears and the strange things that is in between !

[Tom Conen]

When I'm recording I like peak meters to check the peak : checking the level with only a Vu meter seems awfull (and dangerous) to me. I like double mode Vu+peak we can find on SD's devices.

Peak meters are essential for any work within the digital domain. I would never recommend to only use a VU meter. And the double mode is a great tool.

The best loudness meter i know... is my 2 ears and the strange things that is in between !

Very true. If we would only rely on visual reference, we would not be sound guys.

What is your experience regarding LUFS compared to VU meters. How well do they translate to each other?

[Marc Wielage]

More and more final mixes have to be approved according to the ITU-R standard (EBU-R128), so that seems to now becoming the standard, at least for TV and home video mixes. It's a pretty effective way to check average levels, especially for dialog.

Recording on location is a whole separate issue, covered many times in past discussions. I try to let dialog peaks hit about -10dBfs on the mix track, but I'm at least 5dB more conservative on the iso tracks. I think this boils down to individual preference, as well as what the client asks for. I'll also tend to go a little higher if I know it's not for broadcast or theatrical (like a small industrial project), and may not get much of a final mix. I agree that the double mode (VU + peak) is very useful in recording.

--Marc W.

[John Steigerwald]

I like VU's for a reference but also feel they're a bit dangerous to rely on solely.

In the tape days, an overshoot that the VU couldn't display fast enough wasn't such a big deal. With digital's hard ceiling, I really like to know every bit of level I've got.

I run VU/Peak 99% of the time.

[Tom Conen]

Hi Marc!

Can you tell, how well the ITU-R (BS.1770) standard translates to VU metering?

Have you used a LUFS meter on location?

[Marc Wielage]

No, I'm not in a hurry to use an LKFS meter on location. There are too many issues related to size and power that wouldn't work for what I do. On the mixing stage, sure, I would expect they'd use an ITU-compatible meter for the final mix.

This explanation from TC Electronic (who makes a hardware meter system) explains some of the background on the new standard. I think the bottom line is that standard VU meters get fooled in terms of EQ and compression and won't necessarily tell you average program loudness -- more like peak loudness, based on a certain scale. The Dorrough meters came close, but the new meters at least display an "idiot proof" number that tells what the average and peak program levels are. Good or bad, this is very quickly becoming the new standard.

There's a good paper on the theory behind the meters at this link:

Toward a Recommendation for a European Standard of Peak and LKFS Loudness Levels

The advantage of this system is that they can send the post house a list that says, "here are the timecode numbers where your mix exceeds the limit or doesn't hit the levels we want." The disadvantage is, the meter can't say whether the mix is good or not -- only that it meets the standard for levels.

--Marc W.

[studiomprd]

Metering, like so much other stuff that wasn't simple to begin with, keeps becoming more complex...

For dialog recording the old BBC PPM meters were typically preferred over VU's, and many of us still are big fans of the Dorrough meters (hardware, or even software)

[Marc Wielage]

The BBC-style PPMs always kind of threw me, but I think that's because VUs were too ingrained in my DNA (even before I was a teenager). I had no problem adapting to digital peak-reading meters like the Tektronix 764, which was great. The Dorroughs were pretty good, too. Some of the modern meters are programmable, so you can get rid of some of the extraneous stuff you don't need, or turn on extra channels and other stuff needed for certain kinds of mixes.

I haven't tried the new fancy-schmancy ITU meters yet, but I may check them out, the next time I get thrown a final mix (which only happens once in a blue moon).

--Marc W.

[soundtrane]

My point is that LU or ITU style metering has no place in production recording, listening on headphones. I tend to rely on my listening skills and occasional glances at the Cantar 'modulometers'.

From the Cantar Manual:

They feature a non-linear scale with increased

resolution (1dB) in the most important range: -55 to

-40dBFS (5dB per segment); -40 to -32dBFS (2dB / segment);

-32 to -12dBFS (1dB / segment); -12 to 0dBFS

(3dB / segment).

The peak level segment hold duration is adjustable from one half

to five seconds...

//

The ballistics emulate needle modulometers. The decay time

can be adjusted in TECHSET.12 'Meter Speed' from '1 (fast) '

to '5 (slow) '.

[studiomprd]

" needle modulometers "

what Dr. Kudelski designed specifically for the needs of those using NAGRA recorders...

New regulations require broadcasters and content producers to carefully manage audio levels according to a complex set of standards and guidelines. It’s no longer adequate to simply watch levels via VU or peak meters and “keep it out of the red.”

Just what the doctor ordered, and it is free:

https://event.on24.com/eventRegistration/EventLobbyServlet?target=registration.jsp&eventid=385322&sessionid=1&key=49E5A520820B77D8829CA5988EB7CDA1&partnerref=RTUpdateDec2&sourcepage=register