Updated October 2026 · Levels and metering explained
Levels drift in long sessions because the speaker moves, tires or changes posture, and the room and equipment can also shift. Keep the microphone position fixed, check the level during breaks, and correct drift with gentle gain changes in editing. A steady setup and a short check every so often prevent most of the problem.
A recording that starts well can drift during a long session. The voice grows quieter, or louder, or thinner, and the change is gradual enough that the speaker does not notice. By the end of an hour the sound may be very different from the start. Drift is common, and it is largely preventable with a steady setup and a few simple habits.
This post explains the causes of drift, how to keep a session steady, how to correct drift in editing and when a re-record is the better answer.
Speakers move. They lean back in the chair, turn toward a guest, or shift their weight, and each movement changes the distance to the microphone. Voices also change as the session goes on: the speaker may relax and speak more softly, or tire and lose energy. The room can change too, as the heating comes on, a door opens or a fan starts.
Each change is small, but the cumulative effect can be large. A distance change of a few centimetres can shift the level by several decibels.
The most effective fix is a fixed microphone position. Use a stand or boom arm that holds the microphone steady, and mark the position of the speaker’s seat and head. Ask the speaker to stay in the marked position, and remind them during breaks. A fixed setup makes most drift disappear before it starts.
Pause the session every twenty or thirty minutes, and check the level with a short test. Ask the speaker to read a sentence, and compare the level with the start of the session. If the level has moved, adjust the microphone position or the gain before continuing. A short check is much cheaper than discovering drift at the edit.
A speaker who tires may speak more softly and flatly, which lowers the level and thins the voice. Build breaks into the session, and encourage water and short pauses. A rested speaker produces a more consistent performance, and it is easier to keep the level steady.
Drift that has already happened can be corrected with gentle gain changes. Split the recording into sections, and level each one to match the start. Use small changes, and check the joins by listening. Avoid lifting the quiet passages so far that the room noise rises with them, and consider light noise reduction on the sections that were quiet.
If the drift is large, or if the voice has changed in tone as well as level, correction may not be enough. Re-recording the affected section, with the microphone reset, is often faster and gives a more natural result. Keep the good sections, and replace only the parts that have drifted.
A long session is easier to keep steady when it is split into blocks, each with its own setup check. Plan three or four blocks of about twenty minutes, with a short reset between them. At the start of each block, confirm the microphone position, run a short test and note the level. The block structure gives natural points to correct drift, and it stops a small change from growing unnoticed across the whole session.
Keep the blocks consistent from session to session. If the same structure is used each time, the sound of the finished episodes will be more alike, and the editing will follow a familiar pattern. When the blocks look the same across sessions, a change in one of them stands out at once, which makes the drift easier to catch and correct early in the work. Keep the block notes with the session files, so the next session can start from the same structure. Note any block that needed correction, and the reason for it.
Some drift is natural, because voices change with energy and emotion. The aim is to keep the sound consistent enough that listeners do not notice the change, not to remove every variation. A performance with natural dynamics is better than one that has been levelled into flatness.
A steady check across the session shows whether drift is happening. The Vocal Checker shows clipping, noise and level problems in a recording you own, which helps you spot drift in a test. The LUFS meter shows the loudness of the finished file. For the setup that prevents drift, read the consistent sound post in this series.
Integrated LUFS, true peak and streaming targets. Runs in your browser, nothing is uploaded.
Movement of the speaker, which changes the distance to the microphone.
Every twenty or thirty minutes, and at each break.
Partly, with gentle gain changes. A large drift may need a re-record.
Yes, slightly, as heating and doors change the room. Check during the session.
