Dynamic range metering and loudness metering

They’ve been around for a couple of years, but dynamic range and loudness meters still aren’t that widespread. We’ve recently starting using both for mastering and thought it was high time we offered up a primer.

Dynamic range metering

Dynamic range metering is specifically for use in mastering, although there’s no reason you shouldn’t use it earlier in the chain. TT dynamic range meter is the only such meter we’re aware of, which is brought to you by the Pleasurize Music Foundation (a collaboration between various plug-in developers). The production of the meter is part of a broader mission to reintroduce dynamic range to recordings and make them more pleasurable to listen to following the hyper-compression of the loudness wars. It can operate in real-time, but more useful is the offline meter which gives you a single number value of dynamic range. This is broadly similar to the crest factor of the recording (the difference between peak level and average/RMS level) but slightly different due to statistical weighting. Obviously you have to use your ears to tell you if something is over-compressed or not, but the dynamic range meter is a handy indicator of whether you’ve gone too far or not, particularly when used in conjunction with their lovely genre-specific infographic guide to what you should be aiming for (right).

Loudness metering

RMS meters have been used for years as de facto loudness meters, by giving the average level rather than peak level they offered a much more useful approximation of loudness than PPM meters. However, when it comes down to it, something that registers at 0dB on an RMS meter can sound much softer or louder than a recording of an equal level. Loudness meters measure the average level of a recording, but filter it with a specific frequency weighting designed to more closely mimic how we actually hear recordings. This way you get a much more useful method of comparing subjective loudness between recordings measured in Loudness Units (Decibels are so last year). They’re more widespread in broadcast work where standards have already been set for loudness. Although the use of loudness meters isn’t mandatory in the UK as of yet, it will be within a few years, partly in an effort to control the programme/advert loudness difference. We’ve started loading one of these up in mastering projects (using the excellent PPMulator + plugin) and they’re very interesting indeed. They will undoubtedly become more common over the next few years, so it’s worth familiarising yourself with one if you’re serious about professional audio work (particularly in film and TV). Audiocation have produced a free loudness meter that you can download here. Naturally, if you’re curious, we’re happy to provide Dynamic Range and Loudness Unit values free of charge when you use us for mastering. Just tell us you’d like them when you contact us with your project details. Have you tried dynamic range metering or loudness metering?