Cumulative RMS Meter?

[seanmccoy]

Is there such a beast? Lots of integrated readouts for LUFS for broadcast and such, but the only RMS meters I have are strictly realtime. I'm editing an audio book, and my RMS meters seem to show generally 2-3dB higher than my LUFS (LKFS), but I'd like something a little more accurate. My extensive searches have been fruitless. Is this a quest of pure folly?

[nucelar]

Hi
Before the general availability of loudness plugins I used to use Audioleak, which is very comprehensive offline metering tool. It will create a rms graph and overall average.

[seanmccoy]

Originally Posted by nucelar

Hi
Before the general availability of loudness plugins I used to use Audioleak, which is very comprehensive offline metering tool. It will create a rms graph and overall average.

Thanks, this looks useful. Since there doesn't appear to be an AAX plugin that will do this, standalone looks like the answer. With all the sophisticated metering options today, I'm pretty amazed at the difficulty of measuring RMS.

[minister]

RMS is not as accurate as LUFS.

[seanmccoy]

Originally Posted by minister

RMS is not as accurate as LUFS.

Understood, and because I do a lot of work for broadcast, I'm comfortable working that way. But ACX and other on-line audio and video distributors often give audio specs in RMS averages, and I'm concerned over the translation. Kinda OCD, ya know.

[nucelar]

Hi Sean,
From my experience, when they state "average RMS" (which is as ambiguous as it gets) they mean "the rms meter moves around x dB" during realtime playback, not a mathematically accurate average.
I've seen many nonsensical specs during my life, and one has to read between the lines sometimes and apply common sense.

For example a RMS total average over one hour would include the pauses in the calculation, resulting in an artificially low value, compared to what you see on the RMS meters when you speak.
On the other hand, LUFS uses some perceptual weighting which can make the figure lower than RMS, as you experienced.

Considering the dynamics of an audiobook is fairly narrow, I would just keep an eye on the realtime rms, adjust master gain as needed and stick to a comforatble monitoring level.