Audio is usually the last piece to be finished in a typical production. As such, audio editors, sound designers, and mixers tend to get the short straw when it comes to time and budgets. If there is ever a mad dash to the finish or squeeze on resources, you can bet it’s going to impact the audio team.
The question remains, how can we streamline audio post production to give audio professionals more time for creativity and experimentation while decreasing compromises due to time constraints? Clearly, despite shrinking schedules, the same amount of work still needs to be done. One solution lies in taking many of the manual, time-consuming tasks and automating, or otherwise accelerating, them.
As we talk to sound editors and mixers around the world, one thing has been clear: ADR (Automated Dialogue Replacement) remains a painstaking and expensive task. ADR is necessary because sound captured during shooting/production can sometimes be unusable. But not only is it expensive to transport actors to controlled environments to re-voice their lines, it’s also very difficult for actors to recreate the emotional intensity of their on-location performance.
For these reasons, production sound is almost always preferred from a performance and authenticity perspective. The good news is, much of today’s production dialogue is completely repairable, thanks to modern noise-reduction technologies (as long as the actor is not in an actual flying helicopter or standing next to a loud wind machine, of course). And as our world becomes increasingly noisier, salvaging production audio remains an inherent problem for every modern production.
With reality television in particular, there are numerous challenges in addition to ADR. On-location sound recordists do their best given the unique situations they find themselves in, but due to the nature of these shows, there is more shooting “on they fly” with minimal time for setup and testing than ever before. Locations are more extreme, and often you only get one shot at capturing an acceptable take.
Audio from these types of shows may have a host of problems, from 50/60 Hz hums and buzzes due to bad ground connections, to distortion and clipping since level checks were non-existent or rushed. There may be very little level at all, and turning up the gain will bring up the noise floor too. Add a healthy portion of unwanted background noise, and the challenges increase. For all these reasons and many more, audio repair tools have become a necessity for audio and video editors alike.
Cleaning things up
The first step to solving these issues is to simply listen and discern the most objectionable audio issues. Is the audio loud enough? Is it distorted? Is background noise distracting or otherwise making the dialogue unintelligible?
Once you’ve isolated the issue, it’s time to fire up the tools. Using iZotope’s RX 4 as an example, it can be very useful to look at your audio in the Spectrogram display. The Spectrogram helps you clearly see the problems you are trying to fix. If there are occasional clicks from jewelry/costumes or bumps from lavalier mics brushing against clothing, you might want to utilize Spectral Repair. Cell phones? Sirens? No problem.
This is a very unique way of looking at sound spread across the frequency range. It takes a moment to get used to the spectral display if you’ve never used one before, but once you start, you’ll never go back.
Using a brush tool, you can paint the offending noise right out. Some noises are easier to see than others, but playing across the section a few times on the display will help. Low-frequency sounds are on the bottom of the display. If you have constant or “steady-state” background noise with your dialogue, you could use a real-time denoiser plug-in like Dialogue Denoiser directly on the dialogue track in your editing application. All denoiser algorithms need to “learn” the offending noise somehow. Fortunately, RX does this automatically. RX’s “Auto mode” will even adapt and remove new noises if the noise changes.
If you have more constant popping or clicking in your audio, the Declick module or plug-in might save more time. A useful tip is to output “Clicks only” to your speakers while previewing the Declick process. This lets you hear exactly what you are removing, so you can avoid removing too much as you adjust the sensitivity control.
Distortion or clipping has caused many otherwise valuable takes to be relegated to the cutting room floor in the past. It can seem like magic when a distorted clip that at first appears beyond hope, is healed with advanced interpolation techniques that intelligently rebuild missing parts of the clipped audio. So, the next time someone says the audio is ruined in this way, try the Declip tool. It can astound and amaze!
Advanced rescue techniques
In addition to the techniques and tools above, there are still more tools that can save the day when it comes to rescuing your audio. In reality TV shows, crews are typically running around following the action. That can lead to audio levels constantly varying up and down. While it’s possible to adjust them with the mouse in an editing application, it takes an enormous amount of time—and time is the one thing we all agree we are short on. Thankfully, there are intelligent leveling tools available in applications like RX 4 that automatically go through and smooth out the bumps in volume. They can do so in accordance with today’s loudness specifications as well, freeing up for more time for creativity.
Additional “magic” tools make it possible to remove room reverberation from audio, automatically match dialogue sound from two different microphones or locations, and even add back useful noise, such as background ambience, to perfectly smooth out edits when the natural ambience is lost or shifting between cuts.
Thankfully, times have changed, and so have the tools we have at our disposal. So the next time someone is about to toss that perfect performance because of sound quality, be prepared to save the day thanks to these powerful tools!
iZotope offers a free Audio Repair and Enhancement guide with detailed information and tips for restoring audio using the latest tools. The guide can be downloaded from www.izotope.com/en/support/support-resources/guides