Post sound — dialogue edit, ADR, Foley, effects, music, mix and stems

• Locked picture — A reference video with burned-in timecode. It is the picture all sound work follows.
• Audio interchange file — The tracks exported from the editing software, typically as an AAF. Ask for handles (extra media before and after each cut) so the sound can be blended smoothly.
• Production sound originals and sound reports — Used to find other mic tracks or alternate takes that aren’t in the interchange file.
• Spotting notes — The scene-by-scene sound and music requests agreed with the director.

Temp music laid in during the edit must be replaced with final music or properly licensed before delivery. Directors who get used to the temp score often find new music unfamiliar, so agree on a direction with the composer early.

The dialogue editor chooses whichever sounds clearer between the boom and lav tracks, and swaps in the same line from another take when needed. A background that cuts off abruptly at a picture cut sounds awkward, so gaps are filled with room tone recorded on location to keep the sound continuous.

ADR is used when production sound has heavy noise or a line needs to change. Actors watch the picture and re-speak the line in sync with their lips, but it’s hard to recreate the emotion and perspective of the set, so look for ways to save the production recording first.

• Foley — A Foley artist watches the picture and performs sounds like footsteps, cloth rustle and setting down a cup, which are recorded in sync. Production sound is focused on dialogue, so these sounds are often weak.
• Sound effects — The sounds of events on screen, such as doors, cars and gunshots. They come from recorded libraries or are created new.
• Backgrounds — The air of a location, like the murmur of a street or wind in a forest. Laying them under the picture keeps the space continuous across cuts.
• Music — Either composed for the film or licensed. For existing tracks, the scope and term of use are set by contract, and the tracks and durations used are listed on a music cue sheet.

The first rule of the mix is clear dialogue. Shape the level and tone of music and effects so they don’t mask it, and add reverb that suits each location to match the space. Channel configuration, such as stereo or 5.1, and the overall loudness spec follow the recipient’s delivery spec.

Stems are the final mix split into groups such as dialogue (DX), music (MX) and effects (FX), each exported as its own file. They are built so that playing all of them together at unity equals the full mix. When you cut a trailer or need to replace only the music, you don’t have to remix from scratch.

A mix usually starts with a temp or pre-mix that you review and revise with the director before finishing the final mix. Check it not only on the mix room speakers but also where viewers will actually listen, such as TV speakers and earbuds.

The M&E is a track with only music and effects, leaving out the dialogue. Dubbing into another language puts new dialogue on top of it. Watch out for footsteps and prop sounds mixed into the production dialogue tracks: when you remove the dialogue, those sounds disappear too, so in the M&E the gaps have to be filled with Foley and effects. That’s why you schedule separate time for the M&E and listen through from start to finish with the dialogue muted.

Moving non-dialogue sounds out of the dialogue tracks and onto effects tracks during the dialogue edit makes the M&E much lighter work. Even without plans for international sales, you may be asked for one later, so it’s a good habit to keep the groups cleanly separated from the start.