For Stem Mastering, you would first organise your projects separate instrument channels into suitable groups that closely match (“stems”) then export the audio into different stereo files.
Example 1: for an electronica track:
Stem 1: bassline
Stem 2: kick-drum
Stem 3: Other drums
Stem 4: Delicate synths
Stem 5: Rhythmic synths
Stem 6: Reverb
Example 2: for a rock track:
Stem 1: Vocals
Stem 2: Drums
Stem 3: Bass
Stem 4: Lead guitar & guitar effects
Stem 5: Rhythm guitars
Stem 6: Reverb
We mix the stems back together then tweak each stem individually (e.g. EQ the vocals separately/run the drums through analogue processors/compress & EQ the bass and kick to work best together etc…) so each stem is optimised in the context of the track pre-mastering.
This neatly helps prevent things like the bassline & kick getting muddy, & allows us to EQ things separately that are in the same broad frequency range (e.g. on a regular stereo mix if you lower an EQ band on a synth sound then other sounds will also be affected, for example).
NOTE: Get your mix as close to how you want it as you can before separating the stems – hearing your intention is the best way to describe to me what you want. Imagine the difference between explaining to a graphic designer the sort of thing you want in words Vs. handing them a rough pencil drawing and saying “like that, but better”. Clearly the second approach will give results closer to what you want – So get your mix as close as you can to how you want it, then tell me what you do/don’t like about it.
Then once that is sorted, we mix all the stems into a stereo bus & do a regular mastering job on it, but with the added luxury of being able to instantly tweak individual stems once the master is close to completion.
Stem mastering also gives you more flexibility – we’ve had several clients who have had a track they just couldn’t get the vocal to sit perfectly over the mix – very frustrating! So we can do a 2-stem job with the instrumental & the vocal stem, making everything sound sweet & balanced for only a few pounds on top – nice!
If you have more than 6 stems in your song, you will get better value from ourAnalog Mixing and Mastering packages.