Noise On Set: Don’t Fix It In The Shrinkwrap
It was the late Frank Zappa who shone a light upon the music industry’s growing trend for ignoring recording problems and expecting the mix engineer (or even the mastering engineer) to correct them. He said, “We’ll fix it in the shrinkwrap”. But if you think that this is a problem confined to recorded music alone, think again. Following the introduction of audio restoration systems in the 1990s, and then dedicated dialogue noise suppression systems a decade later, there has been a growing trend for sound recordists (or, more commonly, the budget-starved directors issuing instructions to those recordists) to ignore noise problems on the basis that everything can be fixed up by some clever bod wielding a suitable bit of software in a post-production suite. And it’s not true.
There are all manner of noises waiting to pounce upon the unwary. One manufacturer lists traffic, aircraft, the noise inside vehicles, air conditioning, wind, rain and other water noises, crowd noise, the noise from domestic appliances, faulty equipment, and even excessive reverberation. And this is still an incomplete list of the problems that can render your recordings poor or even unusable. Some of these should be easy to overcome. You shouldn’t be on set if you haven’t checked your equipment beforehand and everyone should be trained not to place audio cables across AC mains cables, nor to place microphones next to air conditioning units. Additionally, every mobile phone on a set should be switched off, not just because someone’s is bound to ring at the worst possible moment, but because they can induce the familiar beep-beep noises into recordings as they hunt for networks. Anyone who brings such a device on set should, of course, be taken outside and stood up against a wall until the revolution comes, but other problems are harder to avoid.
If you’re on a large set, it’s unlikely that you’re going to be able to silence every piece of equipment, nor everyone in the large crew, nor the hangers-on who always manage to gain access. So how can you ensure that your audio is going to be acceptable and that no audio post engineers are going to be baying for your blood? One solution is to perform an approximation of the necessary noise reduction to judge the recording’s acceptability at later stages of the production process. Some time ago, I was on the set of a large Hollywood production, and the sound recordist had on his trolley a real-time dialogue noise suppressor of the same type as would likely be used in post. He recorded two audio tracks for each channel – one containing the raw audio, and the other recorded through the noise suppressor. He was then able to monitor the raw tracks as usual while recording, but within seconds of the end of the scene he had checked the processed tracks to see whether, in his opinion, they would clean up successfully in post. When the director asked whether everyone was happy, the recordist was able to confirm whether the audio would be useable or not. On one occasion, I watched as more than one hundred extras were moved back into position, the stars took their places, and a scene was reshot on his advice. Although this involved time and expense, he saved the production large sums of money by reducing the amount of ADR to a level that would otherwise have been unachievable.
Of course, not every production can afford to duplicate equipment in this way, but nowadays it’s largely unnecessary. Many of the software systems used in post will run on a modern laptop. Similarly, noise suppression hardware is now portable and often runs on conventional 12VDC power sources, so there’s no reason why you couldn’t take a unit to the shoot in your equipment bag. So, while you’re learning about good mic positioning, learning how to check your equipment, and learning how to avoid obvious electrical problems, learn how to perform basic noise suppression in real-time on set. If you do, the audio post engineers will respect your work and you may even find more of it coming your way.