Matt mentioned using a reference song and IMO that is critical. A reference song of the same genre, instrumentation, volume, etc. of the project you are working on is invaluable and even more so if you are very familiar with the song.

Ozone has a feature that will attempt to master your song to match the reference assuming, of course, that you have a good mix and that the songs are very similar.

I think mixing and mastering are a mashup up of art and science.

There are many conventions but few absolutes.

Bud

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