Truth be known that the loudness war freq live in the 600hz to 3.6k. This is where all the most energy is captured and can translate across just about every playing source. From your mom’s Kitchen radio to your subs in your Car.
The best way to use this is to add the plugin on your master bus. Now I have to be clear, this is not for mastering audio. It is just a great place to have your mix when sending to clients and or your ME. Use the high & low pass filter of your favorite Eq, Setting each at those 2 areas. once in place you can slowly move the lower freq to lower HZ to hear when it all comes to life without the muddiness. Same goes for the K end of the music.
Once those ares are working as desired, using a spectrum analyze watch what freqs shoot above the rest. Once you note the areas, solo tracks in your DAW and see which is creating the over spikes. Keep in mind though the vocals and maybe guitars will be one of the audio tracks creating the spike. Its a good practice to have caution for that reason since, it actually needs to poke out more then the rest of the tracks.