FAQ: Questions from the Listening Seat
Short, honest answers to the questions that come up in edit suites, on set and in late-night messages.
Start with the symptom
Each answer points to the guide where the topic is covered in depth: Foley, Ambience, Dialogue and Mixing.
Missing a question? Write to the sound desk.
How long should I record room tone?
At least thirty seconds per setup, and sixty if the space has slow changes such as air conditioning cycles. Use the same microphone and position as the dialogue, with cast and crew still. More in the ambience guide.
Do I need a Foley stage to record Foley?
No. A quiet, acoustically dead room, a few surfaces — gravel tray, board, carpet — and a close microphone are enough for most small projects. The performance matters more than the facility.
Should I use a boom or a lavalier microphone?
Use both where possible, recorded to separate tracks. The boom gives natural perspective and room; the lavalier gives consistency in wide or noisy shots. Choose per line in the edit.
When is ADR the right choice?
When a line is unusable because of noise or performance and no alternate take works. Match microphone, distance and room so the replacement blends with the surrounding production sound.
What loudness should my film target?
It depends on delivery. EBU R 128 specifies −23 LUFS; ATSC A/85 specifies −24 LKFS; Netflix specifies −27 LKFS dialogue-gated. Always confirm the current specification with your distributor. See the mixing guide.
What is the difference between a J-cut and an L-cut?
In a J-cut, the next scene's sound starts before its picture. In an L-cut, the current scene's sound continues over the next picture. Both soften cuts and carry emotion across them.
Can I mix on headphones?
Yes, with care. Headphones reveal detail but exaggerate stereo width and can mislead on low end. Check on speakers and a phone before delivery.
Why does my dialogue disappear on phones?
Usually because music or effects mask the 2–5 kHz range where consonants live. Carve space in those layers rather than raising the dialogue alone.
Are sound effect libraries acceptable?
Yes, if properly licensed. Layer and edit library sounds to fit the scene, and combine them with your own recordings to give the film its own character.