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Love them or loathe them, lavalier microphones (a.k.a ‘lavs’, ‘personals’, ‘radios’ or ‘bugs’) are an integral part of every sound recordist’s life; and managing the positioning of a lavalier microphone for best clarity, versus concealing it for the best look, is a constant and enormous challenge for anyone engaged in modern, professional dialogue sound recording.

For documentaries, News recording or the presentation of live sports programming on television, it’s easy – just make sure that there’s a neat cable loop underneath the on-screen talent’s lapel or tie-clip, and it’s fine to have the microphone visible, right there in shot. The viewers know it’s there and can accept that without that microphone, they wouldn’t hear what the presenter has to say.

But in a drama situation, to see a microphone in a shot – either a boom or a lav – is to break the spell of ‘the fourth wall’: an old theatrical term that was applied to cinema and then appropriated by television, where a magical, imaginary plane separates the actors from the audience; and by transgressing this, it acknowledges the existence of an audience… Which is obviously not ideal for the suspension of disbelief required for successful narrative filmmaking.

So, the compromise position, before the days of radio mics on actors, was that booms would stay out of frame and the quid pro quo would be that directors and camera operators adjusted the headroom of their shots – and Directors of Photography the positioning of their lighting – to allow a microphone to be kept just out of the top of frame, and in an ideal operating position for the type of microphone that was mounted at the end of the sound operators boom arm: be it attached to one of the ancient but magnificent ‘fly-by-a-series-of wires’ Fisher booms in a studio environment, or a hand-held fishpole on a location set.

Fast forward to today, and it’s de rigeur to rig a concealed radio mic on each actor in a scene, with little or no consideration from directors and DoPs towards the need for a boom microphone to still be accommodated at its optimum working position – and this, I suggest, has had a two-fold consequence: the first is a dangerous, blind assumption made by every other department on set, that the body-worn microphones are picking up everything the sound recordist could possibly need; whilst the second assumption is that because radio mics exist, the boom is some kind of old-fashioned shadow generator and something that’s not really needed in modern moving picture production. (Which is why, I suggest, you seldom hear audio perspective anymore in drama. Irrespective of the framing of a shot, the sound remains relentlessly in close up.)

To address the first point is to lay-out the most obvious physical and acoustical headaches that any sound recordist faces – at its simplest, placing a lavalier beneath clothes can cause rustle to be heard on the capsule, and the insulating effect of clothing on top of the capsule compromises the tonal quality of the actor’s voice; and fixing a mic beneath an actor’s shirt is the equivalent of you placing your ear directly onto their chest: the sound you would hear would come mainly from their chest cavity and not from their mouth, travelling through air, on its way to reach your ears. It’s an unnatural sound. Which is why a boom microphone still remains a sound recordist’s prime choice for recording the most natural sounding dialogue on set; (as well as it being an essential addition to ‘open’ the sound from a lavalier microphone, when the recordist blends in just enough of the boom to not cause phasing or comb filtering issues, when the two mics are combined in the guide mix delivered from location – and because of this, the wise production mixer keeps the two microphones separated on their own isolated recording tracks).

As a drama recordist, I’ve tried all manner of personal microphone mounting gizmos to help ensure rustle-free positions whilst hiding a lavalier (they can make a huge difference, but trouble-free placement still remains a black art); and I’ve tried a multitude of places for the microphone capsule to sit: in the valley naturally formed by a woman wearing a bra (which is why for both parties, a female sound assistant is worth their weight in gold), in tie knots, under a man’s formal shirt collar or between their shirt and the button hole placket. I’ve had success placing a mic under the peak of a cap and even threaded a mic into the knitted collar of a T-shirt; a technique taught to me by the legendary Hollywood Production Sound Mixer David MacMillan (look for the tiny, but tell-tale bulge in the collar of Keaneau Reeves’ T-shirt next time you watch the movie Speed).

This routinely assumed reliance on radio mics also gives rise to the practice of shooting dialogue scenes with ridiculous headroom (‘as if the actors were all wearing invisible top hats’, as one recordist impatiently observed recently) as well as the recordist’s conundrum of the director choosing to shoot tight and wide shots, on two cameras, simultaneously… ‘So is that close sound or wide sound you would like me to capture?’

What I’m trying to convey is the considerable amount of trouble personal microphones can give a sound recordist, with little in return by way of any increase in audio fidelity: a professional system is expensive, a faff to fix, it’s an embarrassment to keep adjusting and for the most part, sonically inferior… Success, at best, might result in ‘Hey, I’ve got a £3,000 microphone channel that almost sounds as good as a £1,000 cabled boom mic.’ But it’s just not as reliable.

Booms in shot can be painted out of course in the picture edit, and these days it can be done easily, without resorting to time-consuming VFX; yet still directors blithely default to relying on radio mics, and dialogue editors expect to see boom and lav tracks for each actor.

It seems that I’ve not got a good word to say about using these personal pests, have I? Well, as a location recordist, if I’m honest, no not really; not for recording crisp, clear dialogue. But there is a place where a personal mic comes into its own: although to appreciate this, I must change from thinking about production sound and consider what goes on in post-production, and therefore talk with my dialogue editor and re-recording mixer’s hat on.

Let’s consider the mix, and an indoors scene with a wide shot. The dialogue sounds suitably open, and the boom is agreeably, and appropriately, delivering the perspective of what we can see on screen. But then – not unreasonably – the director suggests that introducing music could really help the scene along. Which means as the re-recording mixer, I now need to raise the level of the dialogue to compensate for the music that is suppressing it; but when I add more of the boom, I just hear more of the room: what I most notice is the ambience increasing, not the dialogue. This then, is where the introduction of an actor’s lavalier microphone becomes my ‘get out of jail’ card: because by blending in a well-fitted personal mic, it can deliver to me the degree of clarity I’m looking for from the dialogue, whilst still maintaining the natural ambience of the room around it, all thanks to what the boom is hearing. Because whilst artificially re-created aural space is believable in a soundtrack, it requires time to achieve – and time is money on the mixing stage; and so here we can say: ‘Convolution reverb good, natural sound better’.

Lavaliers – whether you love them or loathe them, are a necessary evil, and one that needs handling with care; so they’re unquestionably an essential tool as we strive to deliver location dialogue with effortless intelligibility. But directors and DOPs, please understand the Yin and Yang nature of recording dialogue on set: ‘Every lav needs a boom’; and on behalf of sound recordists everywhere, please let that become your mantra.

© Dr. Neil Hillman 2022

Dr. Neil Hillman is a production sound recordist, a post-production supervising sound editor and an outside broadcast mixer. His book on sound design for non-sound specialists – ‘Sound for Moving Pictures’ – was published by Routledge in April 2021.

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Dr. Neil Hillman MPSE

Brisbane,
QLD 4073,
Australia.

I live and work on the lands of the Aboriginal and Torres Strait Islander Peoples and I recognise them as the Traditional Custodians of this country.

T: +61 (0)431 983 262
E: neil@drneilhillman.com