Taking Your First Steps in Audio Post-Production for Video
Audio post-production is a great way for studio guys to supplement their income between sessions with bands. While there are thousands of professionals who’s full-time job is in audio post-production, the tools used to clean up audio are largely the same plugins and processors we use for our music.
Many of these post-production professionals even use the same DAWs we do, with Pro Tools being the preferred DAW of many of these audio engineers. At its core, Pro Tools has everything you could need for audio work, regardless of if that work is music, audio for film, or any other application. It supports thing like great monitoring, third-party plugin support, and plenty of shortcuts for a lightning fast workflow.
Whether you’re looking into a career doing audio post-production full time, or you’re trying to add another skill set to your repertoire, dialog cleanup is a great place to start. Let’s look at the process for getting the best possible audio quality for your videos.
High-Pass Filtering
For starters, you can clean a lot of unnecessary noise out of a dialog recording using nothing more than a single band of your EQ. By using a high-pass filter to roll off any low-end content that you don’t want, you get rid of things like electrical hum, fair conditioning & even general room ambience that might be distracting to the viewer.
Feel free to set a sharp roll off (24dB/octave) around 60 Hz and commit this edit once you’ve got a sound you can work with – it’s not very likely you’ll need this content back for standard dialog sessions.
Compress/Limit Loud Sounds
Dynamics in speech are much like dynamics in an instrument. They create energy that feeds into the whole feel of the scene. As a result of this, energetic performances will have plenty of loud parts that we need to wrangle in for consistency.
By using a limiter or compressor with a fast attack, we can catch thing like stray plosives and inconsistent peaks in volume in the split second they happen. We’ll want to set our threshold to a level that just barely triggers a few dB of gain reduction on those parts too, which gives us a cleaner, transparent sound than more aggressive compression might.
Remove Room Tone
Room tone is one of the most distracting parts of dialog, especially if the recording was recorded in a different room than the scene is set for. Think of all the movie clips where someone’s yelling during extreme weather conditions. Now imagine those same scenes with the person’s voice bouncing off the walls of the booth or room they’re in when they actually recorded it. It’s a huge buzz kill.
There are several different approaches to removing room noise from your source audio, but one of my favorite ways to pull this off transparently is with transient processors like Transify. Using a multi-band processor, you can reduce the amount of sustain in the mids & low-mids without affecting other frequency bands.
See it in action when Nick cleans up some spoken dialog in the video below:
As an added bonus, you can add a bit of attack to the treble band to add sibilance and clarity to the transients of the voice.
Compress for Presence
Now that we’ve got our cleanup under control, it’s time to make that voice shine! Adding in a bit more compression with a lower threshold can make your voice pop out of the speakers and appear more present/upfront. This technique will still be relatively transparent, since you’re compressing in stages rather than doing all the heavy lifting in one plugin.
As you can hear in Nick’s example above, certain compressors have added features that can supplement your sound. In his case, JW BG-Vocals has a Tone control that adds a bit of presence to the high end specifically.
De-Ess
If you’ve got a big issue with “s” sounds on your source audio, you might want to move this a bit further up your chain. For most dialogs, I prefer to save this step for after my last compressor. Why? Compression can accentuate some of these problem sounds and create issues that might not have been there in the first place. By saving your de-essing for later in the chain, you can be sure that it’s catching everything you want it to, man-made, or plugin created.
Remove the Gaps
The one part of our sound that we still haven’t addressed is the space between each line of dialog. While we’ve done a lot to clean up room noise while the speaker is talking, it becomes quickly apparent when left unaddressed between lines.
The fastest way to remove this is with a gate, but that can sound choppy and abrupt. A better solution is using your automation options to duck the volume or automate a filter that removes the majority of frequencies from the gaps.
Feel like saving some time? Tominator is our solution to removing bleed between drums, but it can also cut down on the time you’ll spend automating the space around your vocals. Give it a try if you’ve got a lot of lines to parse through and not enough time (or patience) to do it by hand.
Beyond Dialog
Once you’ve got perfectly scrubbed dialog, you’re ready to expand into the other parts of audio post-production. This is where creativity begins to become apparent in the process, as the space around your dialog can be rebuilt using time-based effects. Much like music production, audio post makes heavy use of sample libraries, though their samples consist more of special effects and ambient room sounds than the average music producer collects.
Interested in learning more about how common music production tools can be used for video content? Make sure you follow us on YouTube and join the discussion in the Joey Sturgis Tones Forum on Facebook.
We’ll see you there!
