It might appear strange to equate audio with the way you analyse a scene before producing visuals, but take the same approach with sound and it will massively improve your results. – Words Rick Bronks
Last month we had a quick overview of the main mics you’re likely to encounter as you look to start on your audio journey. We’re now going to move on to look at how to use them, and we’ll help you push your skills to take them up a notch or two.
If we go back to the idea that audio is like a ‘viewfinder’ for your ears, it’s easier to appreciate the importance of getting it right and also doing it well. And as your overall video skillset grows, then your audio expertise needs to be following alongside.
When you take out your camera, the chances are you’ve already surveyed the scene in your head. You’ll probably have instinctively identified where the light is coming from, where you should be positioned and how to compose the shot you need. Then you’ll begin troubleshooting to get the environment exactly as you like it, and you’ll have considered which lens to use for the shot. All this usually happens even before the camera is out of your bag.
Audio is no different. When I walk into the location I’m working in, before I even start thinking about cameras and lenses I just stop and listen. As we said last month, your ears are the most important piece of audio kit you have. To prove the point, try this experiment when you get a chance: wherever you are, simply stop and listen, and what can you hear? Is there traffic noise coming from a window? Is there air conditioning buzzing away, floorboards that creak, people in the next office chatting? If you speak, does it echo? There are a lot of sounds that can distract the viewer and potentially ruin your shoot, so this is the time to think about these.
Just as you might make a visual decision based on light, now is the time to evaluate the shot based on the audio in the room. You might find that what looks like the perfect framing for your shot by the window isn’t so great after all, because the noise from outside is loudest there. You’ll also start to notice how certain surfaces will bounce sound off them more than others. Glass, wooden floors, high concrete ceilings and so on can all play a part in giving you a less than stellar sound. Ultimately you might need to re-evaluate your shooting position, based not only on the picture quality but also the sound you’re achieving.
Striking a Balance
Tackling a video shoot is very much a balancing act. Do you, for example, go for the pretty picture with below-average audio, or should you spin the camera round and take up a position where you have more control over your sound, but maybe the visuals you’re now achieving might not be quite so strong as they were before?
It’s a similar decision to the one you might have to make when you’re looking at lighting, and the same adage of ‘use it or lose it’ applies to both. Ideally, we’d want to control everything that’s in the frame, which is why creatives tend to love studios, but the fact is that often we can’t. With lighting we could totally black out a room to give us control over every light source and we could also, in theory, soundproof a room to give us total control over sound.
Both of these options sound tempting perhaps, but are not actually that practical, especially if you’re rocking up to an office to shoot a talking head or an interview. So, we have to learn how to use what we’re given and to make sure not to lose it.
Now let’s imagine a scenario where you’ve listened to the room and you’ve made adjustments in your mind regarding where the camera is going to go. But there’s this annoying constant hum of traffic outside the window. Or we might be shooting outside somewhere, where the audio is largely out of our control.
Obviously we can’t stop the traffic easily, so what’s the best plan? Well – back to the ‘use it or lose it’ train of thought. Let’s see if it’s possible to use the noise. If a viewer can see the source of the noise – in this case let’s say that you’re positioned next to a road – then you need to keep the road in the shot somehow. It doesn’t have to feature prominently, but as long as there is an indication in the shot that there is a road there, and the traffic it’s carrying is making the noise we can hear, then it’s more than acceptable to shoot in that location.
If, however, you hear a sound and you don’t see the source of the noise, then it’s something that could serve to confuse the viewer. The sound being ‘seen’ will help tell the story, so the viewer will just accept that there’s a road there and that road happens to be noisy. Sure, it’s not ideal, but we can’t fully control it, so we’re using it to add some texture and context both visually and aurally. Both audio and video need to work in tandem. It’s not an either-or call.
Getting things right at this stage will save you an age in post-production. While there’s a lot we can do at the editing stage these days to put things right, it does take time and expense and getting it absolutely as right as you can from the outset is always going to be better. It’s a lot to think about before you start rolling, but after a while it’s like riding a bike or driving. In short, it just becomes second nature.
Recording Your Sound
Next we come to the point where we have to make a decision regarding how we’re going to mic-up whatever and whoever it is we’re filming, and how we’re going to record them. Last month we looked at how the lousy built-in microphones on cameras won’t really cut it for professional audio, and how using an external mic is always the best solution. Plugging in a high-performing on-camera mic such as the Sennheiser MKE 400 is a great solution, but what if you want to work with more than one mic?
Let’s start with the basic single mic into the mic socket scenario. If it’s just one person on-camera talking, then generally you can get away with this set-up, but it’s not the ideal solution. All audio usually gets passed through electronics which record the sound, and the quality of these will vary massively across devices.
As a general rule, this means that the in-camera audio isn’t as going to be as good as audio that’s going out to an external recorder. The pre-amps in your camera can be noisy, and if you increase the gain to compensate then you’ll introduce more audio noise into your recording. Increasing the gain is a little like ISO for sound: it’s something you need to do in order to get a proper recording level, based on how loud the source is. If the source is quiet then you’ll have to crank up the gain, just as you would crank up the ISO if the light is low. However, this increase in gain then increases the noise, so there is a trade-off.
Using an external recording device will really help here. People pay thousands for ‘clean’ preamps – and this is why you’d want to go along to CVP and have a listen to different recorder/mic combinations so you can actually hear the difference.
A major benefit of external recording is that this gives you the ability to not only have more than one input, but also control the level of each one separately. This in turn gives you a lot more creative freedom in terms of mic choice, and it will also improve the quality of your final recording.
I have a couple of mixers/recorders that I use, depending on what job I happen to be undertaking. Just like you might select what lenses to take on a job, I plan what mics and recording kit I’m going to pack. When I’m travelling, for example, I take with me a small, six-input recorder/mixer that helps me to work in a nimble fashion. I also use this for recording sound effects and atmosphere for my shoots, and it’s useful to have the unit sitting in my camera bag for those ‘just in case’ moments as well.
For bigger jobs when I’m fully loaded with all my kit, I would use an eight or ten channel mixer, which allows me a lot more in terms of options and variables. If I were recording a theatre performance with multiple mics, for example, this would be what I’d use. I would possibly also pack my smaller recorder to capture sound from a different part of the theatre or even take a feed from the sound engineer’s desk, so that I have a ‘master’ guide track.
With external mixers, you soon realise that the quality of audio is vastly superior to what can be delivered by the in-camera preamps. Not only this, but you can set levels, while some devices offer smartphone and tablet apps that let you see and adjust these remotely. You can also add things like limiters to stop the noise crashing out and distorting, and you also have the option to record each mic on a separate channel, meaning that in post-production you can open up the WAV file and fine-tune each mic separately. We’ll dive a little deeper into this a little later in the series.
Taking your audio recording off and out of the camera is absolutely the best way to do things, but you will then have to look at how to take the audio you’ve recorded and re-sync it with your footage. There’s software around to help with this, while most editing apps will also have some form of synchronisation that’s built in.
The simplest way I’ve found to synch things up is to use the camera’s built-in mic to record everything (yes, badly!) and then to use this as the guide track to synchronise to the main recording. Although the camera mic sound will obviously be rubbish, as you’d expect, as long as there is some level there then editing apps should be able to sync it with your master recording.
Another tried and trusted technique is to do a hand clap in front of the camera(s) you’re using. Then you’ll see the hands clapping together and hopefully you’ll hear the ‘clap,’ helping you line up the shots. A more controlled method of doing exactly the same thing is the ubiquitous clapperboard, of course, and these can also carry helpful information, such as the take you’re on, for good measure.
I realise this might all seem like a lot to think about, but I promise it will all become second nature over time, as will deciding on which mic to use, where to place it and how to get the most from your investment.
And it’s definitely worth the effort. As we said last month, people will notice bad audio way before they will notice poor visuals, so getting the initial stages and set-up sorted well ahead of being ready to roll is really important.
Sennheiser produces a wide range of pro-spec audio products to fit a variety of price points, so head for en-uk.sennheiser.com/microphones to check out the range.
Get an Audio Demo
If you’re new to audio then book up an appointment or a webchat with a member of the CVP tech team at its showroom in London’s Fitzrovia, where you’ll be able to talk to an expert to receive a high level of impartial, commitment-free, brand agnostic advice to help you on your way.
If you’re recording audio in a noisy environment, such as next to a road, try to allude to your surroundings in your visuals to add context.
Recording direct to your camera is never the best solution, and you’ll have a lot more options if you work with a separate recorder/mixer.
Audio is a crucial element in your story telling, so you need to listen to all of the things going on around you to make a call on how to approach your filming.
TOP: When he’s travelling Rick opts to work with a Zoom f6 six-input recorder/mixer that is small to carry and quick and easy to set up.
ABOVE: On bigger jobs when Rick might be fully loaded with all of his kit he’ll opt for the more fully-featured eight-track Zoom f8n.