Boom mic technique: the shot is only as good as the arm holding it

Nothing improves a small production faster than getting a microphone close to the actor. A boom mic overhead, pointed at the mouth, half a metre out of frame, will beat an expensive lavalier buried under a shirt almost every time.

Distance is the whole game

Every time you double the distance between mouth and capsule, the direct sound drops and the room takes over. At thirty centimetres you get dialogue. At a metre and a half you get dialogue plus the room, plus the fridge, plus the street. No plugin puts that back.

• Get the mic as close as framing allows, then ask the operator for the frame line and go closer.
• Boom from above whenever possible, pointing down at the mouth from in front.
• Boom from below when the top of frame is tight, keeping the mic off the chest to avoid boom.
• Follow the actor with the mic, not with the arm alone. Track the head, not the body.

Angle and off axis colour

A shotgun mic is directional, but off axis sound does not simply disappear. It comes back thinner and stranger. Point the mic slightly off the mouth and the dialogue gains a hollow edge that no EQ will fully repair, so aim carefully and re-aim as the actor turns.

Recording levels and headroom

Record at 48 kHz, 24 bit, aiming for peaks around minus twelve dBFS. Twenty four bit gives you enough floor that conservative levels cost nothing, while clipping a shout costs you the take. If your recorder offers a safety track at lower gain, use it.

What lands in post

A boom track and one or two lavs usually arrive as a single poly WAV. Before dialogue editing starts, split it into named mono stems so the editor can choose boom or lav per line rather than fighting a locked multichannel clip.

Our poly WAV splitter reads the track names your recorder wrote and exports named mono files in the browser, with the original sample rate and bit depth intact.