I use the Waves WLM meter on every mastering project. It has precision insight into loudness measurement, metering, and correction. Per the Waves WLM plugin page, "[It's] fully compliant with all current ITU, EBU and ATSC specifications, the WLM Plus offers comprehensive Momentary, Short Term, Long Term, and True Peak readouts, as well as a unique warning and logging system that keeps track of your levels, alerting you when you've exceeded them - or fallen short. WLM Plus also features Gain and Trim controls for correcting loudness levels and a True Peak Limiter, which save you the need to utilize additional equipment or software..."

A music industry colleague and great friend, DJ Michael Motion, turned me on to the tool about a year ago. From then on, it became a critical part of my mastering template.

As an audio engineer working for Spotify, Mike told me that WLM is one of only a few tools required by the service that their engineers must use to provide industry-standard levels. I'm sold if Mike is using it and Spotify requires it!

To get back to the title of this post, Sean Divine outlines how to use this plugin in under five minutes. Granted, he's using it on the output bus on a mix (aka pre-mastering), but the concept is the same for mastering two-track audio.