A single limiter asked to add a lot of level has to handle every peak in one go, and its side effects - distortion, pumping, softened transients - grow quickly. Staged limiting spreads the work across several gentle stages, each doing a small part. Done carefully, it can reach a dense, competitive level more cleanly.
This is an advanced technique outside the taught sequence. Learn to get a good result with one limiter first.
The idea
Each stage only catches the highest peaks of the signal it receives. Because no stage works hard, none of them produces strong artefacts. Typical arrangements:
- Clipper then limiter - a gentle clipper shaves the sharpest transients, then a limiter sets the final level.
- Two limiters - the first, with a slower release, controls the broad level; the second, faster and with true peak limiting, catches what remains and sets the ceiling.
- Compression, then limiting - a bus compressor doing a little gain reduction before the limiter.
Setting the stages
- Small amounts at each stage - often 1-3 dB of gain reduction each.
- Different characters - a slower stage followed by a faster one, or two different limiter designs, so each handles different kinds of peak.
- True peak control at the final stage only, with the ceiling set for the destination.
- Level-match every comparison - bypass the stages together and compare with a single limiter at the same loudness.
Printing in stages
Some engineers finish the mastering chain without its final limiter, print the result, and do the loudness stages in a separate session. That keeps the tonal decisions separate from the loudness decisions and makes it easy to try different approaches. Keep a placeholder limiter in the first session so you hear your decisions at a realistic level.
Watch for
- Too many stages - each adds latency, CPU load and subtle change. Two or three is plenty.
- Accumulated distortion - listen especially to the low end and the top end.
- Lost dynamics - check the crest factor or PLR. If it collapses with little gain in loudness, back off.
When not to use it
If one clean limiter reaches the target and sounds right, use one limiter. Staged limiting is a tool for dense genres and difficult material, not a requirement.
Do this now
- Take a finished master, remove its limiter and print the result.
- Reach your reference's loudness with one limiter. Save it.
- Reach the same loudness with a gentle clipper and a limiter, or two limiters, each doing 1-3 dB.
- Compare at matched loudness: transients, low end and clarity.