Gain Staging AI Stems
When stem levels disagree, fix peaks and loudness before touching faders or plugins.
Related
Levels disagree before the first fader moves
Stems from one generation arrive with the vocal peaking at +2 dBFS, the pad at -20 dBFS and the kick at -4 dBFS. The bus has no headroom left and nothing has been mixed yet. This is not a mixing problem but a gain-structure problem: every track brings its own level reference, and that has to be fixed before balance is discussed.
Peaks first, loudness second
Peaks decide how much headroom remains; loudness decides where the fader sits. Adjusting both at once means chasing your own changes. Use clip gain to bring peaks to roughly -6 dBFS, leaving 6 dB on drums and bass, then look at short-term loudness and place similar material at similar loudness. Vocals and leads should be matched by peak rather than loudness, because their transients differ widely and loudness matching shaves the attacks. Clip gain changes the source; faders stay for balance, so later balance moves do not undo the levels already set.
Checklist
- Play each stem alone and log peak and short-term loudness
- Clip-gain anything peaking above -3 dBFS instead of pulling the fader
- Bring kick and bass peaks to -6 dBFS with 6 dB of headroom
- Match vocals and leads by peak, not by loudness
- Set pads and effect returns 6 to 10 dB below the lead
- Keep the bus below -3 dBFS and leave the limiter off before mixing
- Treat a flat-topped waveform as already limited and do not compress it again
- Write down the amount of every move so a regenerated stem can repeat it
Where it goes too far
Normalising every stem to the same loudness looks tidy and flattens both the drum transients and the swells of the pad. Compressing an already limited stem only adds another layer of distortion. Another common mistake is putting a limiter on the bus to chase loudness first, after which every balance decision is made on squashed material. At the stem stage loudness only needs to be relatively sensible; absolute loudness belongs to mastering.
Listen in the library
All tracks from midicn-lib — inline badge is the license tier (C1 commercial / C2 non-commercial / C3 study only).
Along the same line
Sources
- Bobby Owsinski, The Mixing Engineer’s Handbook 与 Eargle, Handbook of Recording Engineering 中关于峰值、余量与响度的章节。
- 分轨电平与总线余量的处理顺序，依据混音实践惯例。