Location sound overview
In part 1 we looked at the broad overview of why you should care about audio as a digital video producer, and in part 2 we walked through preproduction. In this installment we’ll talk about one of the most critical steps to the audio leg of your production: location sound.
Why location sound matters
Location sound is one of the most critical aspects to your video production. The recordings you take back from the shooting location into post are as critical as the cast, the onscreen performances, the set and the lighting. Why? Because if your location recordings sound bad then the rest of your production doesn’t matter until the issue is resolved. As the person responsible for your digital video production keep this simple and important rule in mind:
- Intelligible, non-distracting audio is the only way to communicate your carefully crafted story to your audience.
Bringing back clean audio from the shoot requires a little ingenuity, a little patience, and a lot of planning to do well. As a digital video producer it may not be your responsibility to record your audio well, but it is your responsibility to make sure that someone on the shoot is. By taking responsibility for the entire production, not just the pictures and on-screen performances, you will be giving your project the respect and professionalism that it deserves.
Entire careers have been devoted solely to the art and science of capturing good audio out in the world, and a number of books have been written about this subject as well. As a first option, you should usually have someone involved in your production who is dedicated solely to the audio. This person will be listening to every recording as it occurs, and can make a number of subtle adjustments on the fly. The times you can skip a dedicated sound person are generally when the shoot is just a single person on camera without tons of movement. If you plan on doing the audio yourself, I would recommend reading the excellent book Location Audio Simplified by S. Dean Miles, as well as Producing Great Sound for Digital Video by Jay Rose as a primer and reference.
What does good location audio sound like on set?
In audio some sins are forgivable and others are not, and knowing the difference can have a major effect on what you're able to do in post. A little experience in audio post production can shed a lot of light into what can and cannot be fixed after the cast and crew have gone home, but here are a few rules of thumb:
- Good sound is not reverberant.
Reverb is one part of sound that just can not be subtracted in post, so its essential to listen specifically for reverb levels in your recordings while on set. Bathroomy reverb is the single biggest problem with the audio in most low end digital video productions, and its the one that can turn your project from legitimate to a home movie faster than anything else. Listen to playback relatively loudly with headphones and be honest with yourself about how much reverb is getting into the recordings. Bedrooms, living rooms and kitchens are generally not the best sounding recording environments, and as such a little care must be taken when recording indoors. Generally having a tight, directional mic pointed right at the on-screen person's mouth is the best solution and often body mics are employed for this purpose as well. If possible, try to dampen the reverberations in the off-camera parts of the room with blankets and drapes. Just don't hang anything flammable on any lights. Built in camera mics are generally very good at recording the reverb in the room and nothing else, so avoid them when making professional level productions. Remember: once the reverb is in, it cannot be taken out.
- Good sound is not distorted.
Distortion is another one of those problems that just cannot be fixed in post. Once a sound is clipped then you should consider the take to be busted for audio purposes. Audio can distort at the microphone, the preamp, the analog to digital conversion, and even the internal compressors and limiters that some stand alone recorders have built into the software. Camera audio circuitry is particularly susceptible to distortion, which is why most productions run a dual-system setup with the primary audio being recorded to a separate audio-specific device. Even high-end cameras tend to have poor audio circuitry, so don't be fooled by the price tag. If you have distortion on your audio then you don't have a recording of that take, so proactively listen to your takes and be honest with yourself when your ears tell you that something clipped. Listen with headphones on the set and listen loud enough to make informed decisions.
- Good sound isn't overly noisy.
When out in the world some amount of noise is going to get into every recording. The trick is deciphering what is acceptable noise versus what is not. Try to listen for the softest words spoken during a take, then ask yourself if the noise you're hearing is louder than the words in those spots. If it is, then you're going to have difficulty during post. Also listen for what type of noise you're hearing.
Wind is the most common source of noise, and if your microphones take a hard wind hit then you should treat the take the same as you would if you heard distortion on the take. Some mics are more susceptible to wind than others, and a small investment in good wind protection goes a long way when shooting outdoors.
White noisy sources like rushing water, heavy traffic, airplanes, and loud air conditioners can generally be minimized to a degree. They can never really be eliminated, but proper treatment can salvage audio that isn't being overrun with the noise. White noisy sources tend to move around a lot sonically though, so be aware that you may have to spend more time matching takes together later on.
Harmonic sources like insects, birds and music are usually there to stay. If the birds are louder than the people then no amount of EQ–ing is going to get rid of them later on, so scout your locations for animals and insects in advance.
Static electrical noises like ground loops and electrical buzzes often are removable. Because the are static sounds they can usually be isolated with noise reducing software and EQs well enough to target and eliminate. This is not to say that you should ignore an electric buzz if you hear it in your audio, but you may not have to call a code-red on your best take if what you hear is reasonable. Most cameras introduce a fair amount of electrical noise with their built in audio circuitry.
The bottom line is that good audio is generally audio that is free of problems. Listen to takes often, ask questions, and trust what your ears are telling you.
So what does good location sound add to my project?
By caring for your audio on the set you’ve given your project a chance to succeed. Congratulations!
Now you are able to communicate your story clearly through dialogue, which means that you’ve got one of the essential building blocks to commercial viability. You have also minimized the amount of foley that you’ll need to do later. A really great set recording can reduce or eliminate the need for ADR (Automated Dialogue Recording) which is very important if you don’t have the budget for it or if you’re going to lose access to your onscreen talent after the shoot ends. Finally, you’ve given yourself a creative opportunity to run a scene without music because the soundtrack can stand on its own and not need the masking cover that music can provide.
In part 4 of this series we will look at how to approach the dialogue edit once you get all of your location recordings back into the studio.
This post is part of the series: How good audio can help your digital video production
- How Good Audio can Help your Video Production – Part 1
- Getting Better Audio in Your Digital Video Production – Part 2
- Good Location Sound – Part 3
- Part 4 – Dialogue Transfer and Editing
- Noise Reduction and Dialogue Mixing: Part 5