The war is over – What is Loudness Normalization (and 3 free Loudness Meters Plugins)

The war is over…

This war is finally ended. There are no winners or losers – it simply became meaningless.

The war of loudness, started way back in the 1940 and becoming increasingly fierce up to the beginnings of the turn of the century – is about to end. Aggressive mastering techiques – using hyper compression and peak limiting as weapons are becoming an obsolete way to make your mix stand out from the crowd. Still, these techniques can be used for artistic purpose – but they will not make your song louder than others when played on Spotify or the likes. They will actually make it sound worse.


The war of the “volume” has lasted long enough to shape the way material was produced – especially when digital recordings removed the tape and vynil physical level constraints. Not only that, but has shaped what we were – and still are – used to expect from a track: squeezed dynamics, extreme control, “compact sound”. Then we would complain about the “good-old” vynil dynamic ranges – but we’d still stick to a smaller sound even when making final home studio premastering decisions. Infact, the digital realm has a lot more dynamic range capabilities then tape – we simply weren’t using it.

There’s is a complete, extremely interesting article on this topic (Sound On Sound released 2014 – link here) – tracing the history of this war-to-be-louder in music, brodcasting services and the audio industry in general.

“As you can probably imagine, during the music industry’s transition from a peak-normalisation workflow to one driven by loudness-normalised consumer outlets, there will be conflicting mastering requirements. Should a track be mastered to sound as loud as last year’s music when played on CD? Or should it be mixed and mastered to be a little more dynamic so that it fares better when played on loudness-normalised radio and streaming services? Decisions, decisions!” (Hugh Robjohns, End of the Loudness War?


For some reference and views about the end of the Loudness War, I also suggest you read this: The Loudness Wars – Thoughts form 62 Mastering Pros @

Where does loudness normalization come from…

My ears do not have a linear frequency response. At a given volume I will be able to hear some frequencies better than others. Our hearing system behaviour in regards to frequency response is graphically represented in the Equal Loudness Contour curves (ELC) developed by Fletcher and Munson in 1933. “An equal-loudness contour is a measure of sound pressure (dB SPL), over the frequency spectrum, for which a listener perceives a constant loudness when presented with pure steady tones” (Wikipedia). In 1956, new experimental evidence by Robinson and Dadson helped define the ELC ISO standards 226.  More recent studies have lead the ISO to revise the standard (now called  ISO 226-2003). The curves of this latest standard present noticeable differences with the 1956 graphs, and, surprisingly, are in better agreement with the “original” Fletcher- Munson curves.

ELC ISO 226-2003 standard
ELC ISO 226-2003 standard

How can we measure Loudness…

The difference between volume (level) and loudness:

  • Volume (level) is an objective measure of the audio signal strenght.
  • Loudness (or perceived loudness) is a subjective measure of an audio signal strenght – (eg. a certain sound can be perceived differently by two different people)

Loudness is an auditory sensation – the amount of signal pressure perceived by the hearing system allows to place sounds on a scale extending from quiet to loud.


When listening to audio streaming services, a playlist from you CDs, TV or even radio, there are sometimes consistent changes in perceived loudness between songs or programs. This is because the intensity that we perceive is determined by various factors: peak level, dynamic range (peak variations – in this case) and frequency content (remember the ELC…)

If you think about it, loudness normalization is a process that has to start during the early stages of the mix. A VU meter or a RMS meters usually are a good reference point, but it is crucial to have a Loudness Meter inserted in the stereo mix channel, if we want to work in a loudness normalized environment.

In the broadcasting world, a loudness target level is determined by the broadcaster (usually between -16 and -24 LUFS – Loudness Units Full Scale) and the meters level will have to be referenced to that target, so that all the audio material is reproduced at an equal perceived loudness. (For example: iTunes Soundcheck is at -16 LUFS).

A loudness meter measures the entire song – or the entire album or playlist – and determines the overall average loudness of the different audio programs – and applies a gain offset to individual tracks when required. Using the loudness normalization standard has ended the need of overly compressed mixes: these mixes will have a higher perceived loudness, so they will be turned down – and sound small and poor in energy, when compared to more dynamic mixes.

It has to be said that standards regarding loudness are a work-in-progress, so you should follow this topic in order to always keep updated with the latest industry requirements. Here’s a very complete and recent article on loudness normalization: “Loudness Normalization”, by Edgar Rothermich (

Some Free Loudness Meter Plugins…

The following plugins are free. Please check compatibility with your system in the manufacturer specs before download. Also, be aware that loudness industry standards are subject to change over time.

  • The Youlean Loudness Meter features International Standard Compliances. It features a Smart Loudness Memory that saves session data and recalls it when reloading the session. It is available for download here.
The Youlean Loudness Meter
  • The Melda Production Loudness Analyzer features a peak meter, momentary, short-term and integrated loudness metersand a loudness range meter. Supports EBU+9, EBU+18 and EBU+27 scales. Full description on the Melda website – you can dowload it here.
Melda Production Loudness Analyzer
Melda Production Loudness Analyzer
  • Hofa 4U Meter, Fader & MS-Pan. This plugin uses the European Standard  EBU R128 scale, but its still a good reference meter, as standards are quite close to each other. Download available on Hofa officila page here.
HOFA 4uMeter
HOFA 4uMeter

So, the loudnes war has ended… because it is now meaningless. Like every war, really. If we could finally realize how meaninless they are – they will probably all end.




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