How to Prepare Stems for Mastering and Remixing
Stems are grouped audio exports from your mix — drums, bass, vocals, synths — each as a separate stereo file. When done correctly, they give the mastering engineer individual control over each group. When done incorrectly, they create confusion and inconsistency.
Here’s how to do it correctly.
What stems are and when they’re needed
A standard stereo master export is one file: the full mix summed to stereo. Stems are multiple files: each major group of elements as its own stereo export.
When are stems needed? For stem mastering — where the mastering engineer applies different processing to different groups. For remixing — where someone needs access to individual elements. For sync licensing — where a TV supervisor wants the music without vocals.
For standard streaming mastering, stems are often unnecessary. Discuss with your mastering engineer before exporting — you may be creating extra work with no benefit.
How to group stems
Common stem groupings:
– Drums (kick, snare, toms, hi-hats, overheads, room mics)
– Bass (bass guitar, sub synth, any 808)
– Harmonic/chord elements (guitars, piano, pads)
– Lead vocals
– Background vocals, doubles, harmonies
– Lead/melodic synths and instruments
– FX and ambience (reverb returns, delays, atmospheric elements)
The groupings should reflect the musical function, not the track count. Drums belong together because they function together. Splitting kick and snare into separate stems rarely helps.
The technical requirements
Every stem must be exported at the same sample rate and bit depth as every other stem. If you export at 24-bit 48kHz, every stem exports at 24-bit 48kHz. No exceptions.
Every stem must start at the exact same point in time — typically bar 1, beat 1, sample 0 of the project. When all stems are imported into a new session and placed at the same starting position, they should play back as the original mix exactly.
This last point is critical: when all stems are summed together, they must produce the original mix. If the summed stems don’t match the original mix, something went wrong in the export.
Verify by re-importing
After exporting all stems, import them all into a new, empty session. Place every stem at bar 1, beat 1. Play back. Does it match the original mix?
If yes: the stems are correct.
If not: you have processing on your master bus that isn’t being printed into the individual stems, or you have routing issues where some elements aren’t being captured by any stem group.
Bus processing: print it or remove it
If you have mix bus processing (a compressor, an EQ, a limiter) that’s affecting the sound of the full mix, you have a decision to make:
Option 1: Remove the bus processing before exporting stems. The stems represent the unprocessed mix; the mastering engineer applies their chain to the sum of the stems.
Option 2: Print the bus processing into each stem by routing the bus output to the stem exports. The stems already include the bus processing character.
Option 1 is typically preferred for stem mastering — it gives the mastering engineer the clearest starting point and lets them apply mastering processing to unaffected material.
Jacob Korn at tailout.de offers stem mastering for clients who need additional control — vocals brought up or down, low end adjusted independently of the mids, specific elements treated differently. A well-prepared stem set turns what might be a revision into a direct fix.
Ready to send your mix? Visit tailout.de — professional mastering with stem mastering available for productions that need individual group control.