Post-Production Basics: Sound editing – Dialog

In part one, we covered file transfer between a video workstation and DAW and how to prep these materials for a sound editor. In this part, we will cover some of the basics of sound editorial.

Different types of sound editing

Sound editing for picture can be broken into different elements (and job titles):

  • Dialog editing (dialog editor)
  • Music editing (music editor)
  • Sound FX editing/sound design (sound designer, sound fx editor)
  • Foley editing (Foley editor)

These roles could be different people or it could be one person doing all of the above. In credits, if someone is listed as “Sound Editor” they likely worked on multiple elements.

Dialog Editing

As we saw in part one, the materials are brought into an audio workstation from a video workstation (through an AAF or OMF) and then “split” so that each element is placed on appropriate tracks. The dialog editor is responsible for going through all of the dialog tracks for the following:

  • Organizing files within each set of audio tracks
  • Sorting through tracks and removing regions so only usable or preferred/best mics are remaining.
  • Once the appropriate mics are in place: adjusting fade ins, fade outs, cross fades, and filling in holes as necessary.
  • Removing unwanted sounds such as pops, clicks, hums, thumps, or other noises that can’t be removed by real-time mixing. Sometimes the dialog editor can remove other non-desirable sounds like dogs barking or sirens.
  • Repairing sounds that can’t be fixed by real-time mixing (such as mic dropouts)
  • Editing ADR (actor’s lines that were re-recorded in the studio) and voice-over narration

The fundamentals of dialog editing

dia edit vs orig.png

Here’s an example of a very basic dialog edit; The above track is edited while the grey track (lower) is how it was delivered by the picture editor (via AAF).

Most dialog clips will need a fade in/fade out to make the ambience come in (or shift to another mic) more naturally.  Production dialog naturally has an audible noise floor (from background noise). For an exterior shot, this could be distant traffic or light wind; interior might be an air conditioner running or a refrigerator hum. In the above example, there’s a small spot where a mic is missing (on the "DIA ORIG" track). The dialog editor would need to “fill” that – in this case, the original audio in that area was clean so the region was extended to fill in the hole. 

Towards the end of the clip (the 5th region), an edit was moved slightly to clean up a bad dialog edit in the middle of a word. At the very end, the original audio had something going on (a noise or start of a new word). That had to be edited to add a clean fade out using audio from earlier in the track.

Removing mics

 Before dialog editing

Before dialog editing

 After dialog editing

After dialog editing

This is a before and after look of two tracks of dialog. It’s two people with separate mics talking at close proximity. Even just looking at the regions (without listening) you can get a general idea of when one person (or both) are talking based on the size of the waveform. Even though it may appear obvious, it’s still a good idea to listen through each track to make sure you’re not removing anything important that’s hidden in the waveform (like a quiet word or laugh). In this example, the second region of dialog came from another scene (this was added by the picture editor or assistant). That had to be replaced with fill that from this scene to match sonically. Sometimes an audio replacement sounds fine in the picture edit bay but not work at all on the mix stage. Sometimes issues like that aren’t audible unless you’re listening with professional-quality headphones, studio monitors, or with a compressor on the dialog.

Dialog organization

There’s a lot of different ways to organize dialog and the style can change depending on a few factors (like the genre of the project or the mixer you're editing for). For example, when working on reality tv shows (or documentary), I like working with two sets of dialog tracks: interviews and in-scene dialog. A scene could switch many times between action (in-scene dialog) to an interview of someone talking about what’s happening. Here’s an example of a show that uses that style:

Even though it’s the same person talking in-scene and in the interview, it doesn’t make sense logistically to have all that  audio on the same track. It’s different locations, different mics (or mic placement), and the source mics probably have different levels and EQs.

That style of dialog editing may not work for a scripted film or tv show, though. It may make more sense to have 5-10 generic dialog tracks. You typically want to edit the same character/same mic on the same tracks through a scene (in a new scene they may switch to a different track). In this example, there’s 3 people (and three mics):

Sometimes the style of dialog editing will be catered to the mixer you are editing for. Below is the same audio but edited to another mixer’s preferences (no straight fades, longer fade ins/outs, switching between tracks A-B and C-D between scenes):

If you're editing for another mixer, it’s always a good idea to speak with him/her before to get a sense for preferences. Some mixers have 5 dialog tracks in their template and others have 20. Some mixers only want a specific type of cross fade. It can help to see another project that was edited for that mixer or to use the mixer's template so names will match. In essence, the dialog editor’s job is to make it easy and seamless for the mixer to import the dialog edit and start working as quickly as possible.

Removing sounds

It’s expected for a professional dialog editor to know how to do detailed audio clean up using corrective software or plugins (with functions like declick, decrackle, and hum removal). Detail work is the focus; Broadband noise reduction (globally reducing noise) typically happens during the mix, not by the dialog editor. 

Izotope RX is commonly used software that dialog editors use to remove problem sounds. It's sort of like Photoshop for audio. In the example below, there’s wind on the mic that’s causing rumble and clicks. The left side is the original audio; the right side is after it’s been treated by RX 5 (to remove low pops, de-plosives and declick):


The biggest change is in the low frequencies (seen as bright yellow at the bottom of the  left photo). What’s impressive is that RX can remove this without compromising the quality of the dialog (with the appropriate settings). A mixer could achieve a similar result with a high pass EQ filter but they would be completely losing low end information – which can cause a shift in ambience or negatively affect the sound of the voice.

Izotope can also repair mic dropouts, as seen in this before and after:

izotope dropout.png

Tips for dialog editing

  • Add EQ and compression to your edit tracks (for temporary use) to listen closer to how the mixer will be hearing it. It may take some adjusting plugins between scenes but the idea is to hear things that you may not catch otherwise. For example, some lavs sound very dull or boxy (especially if poorly placed). A lav might need 6 dB or more of a high end boost – significant enough to hear issues that went totally unnoticed without the boost. I like the  Waves MV2 plugin for compression when editing dialog.
  • Sometimes it’s up to the dialog editor whether to cut a scene with lavs or boom mics but it's a discussion to have with your mixer. Some mixers generally prefer one  or prefer to have both options in the cut.
  • Unused mics: There’s a couple ways to handle mics that aren’t needed. If there’s two mics on the same person and both sound pretty good, it’s ok to edit both and leave one unmuted and the other one muted. You could also make “X” tracks; “X1, X2, etc” and place any unused audio on there. Your mixer may want these tracks or may not (that’s another question to ask). It’s good to hang onto as much as possible in your own work session, either way. If a mixer later asks, “were there any other mics for this spot?” you can easily see how many mic options there were and can listen to the alts (so you can explain why you chose the way you did).
  • If you’re doing any processing (declicking, etc), it’s really important to keep a copy of the original somewhere accessible. Sometimes it’s muted on the track below or you can make a track labelled “unprocessed” (or something similar) so you or the mixer can quickly get back to the original, if needed. If only a small portion of a region is processed (and has handles) and the rest of the region is not processed no copy is needed. In general, you want to make it quick and easy for anyone to get back to the original/unprocessed file.
  • Headphones versus studio monitors: This is a personal preference, but I typically prefer headphones unless I’m working in a good-sounding room with monitors that I know and trust. It’s hard to hear rumble on a speaker that only has a 6 inch woofer, for example. If I’m working at a studio, I would rather edit on a mix stage than an edit bay (it’s not always possible but it’s really helpful if you have the option). Even better is to work in the mix room that the final mix will take place. The mic choices that you make in one room may sound very different in another – especially between a small edit room and a mix bay.

Advanced dialog editing

This has been a basic overview of dialog editing. There’s more advanced skills that come up such as:

  • Removing sound fx that naturally occur in production audio so they can be used in the M&E (foreign versions)
  • Creating fill that can be used for ADR, holes, or used as transitions between mics
  • Adjusting mics for phase or sync issues
  • Conforming lav mics (from the source recording) when they aren’t included or cut by the editor

Who makes a good dialog editor?

Dialog editing is a good fit for people who like to work alone and is generally more independent and less stressful than mixing. You have to be detail-oriented and like problem solving. It’s rewarding because it’s often a drastic change between where you started and what it sounds like when you’re done. Dialog editing can be really challenging at times, too. As far as sound editing goes, it’s probably the most important job (because dialog is up front and center – literally).