How to Secure Backup Audio for Video Projects

Today’s video production has gotten smaller, cheaper and faster paced. Crews with extensive resources are shrinking with more set-ups done each day. Yet, with the cumulative cost of location shoots, the pressure remains on crew members to get it right the first time.

All this may sound fine to the bean-counting suits in production offices, but the responsibility to crew members in the field is greater than ever before. Highly skilled members of crews in each craft is essential to the overall production.

Zoom H5 camera-mounted stereo microphone.

Zoom H5 camera-mounted stereo microphone.

Most television shows and small films now use one, or perhaps two, sound operators. Only on days where major scenes are being recorded are more sound personnel hired. Sadly, in most cases, production moves so fast there is only one chance to get a perfect take on the audio. Missing the best take of the day can get a sound operator fired. The work can be brutal.

When do-overs are the sound operator’s kiss of death, there is a precaution available to always ensure a good audio take. On the most video crews, the answer is to cover yourself multiple ways.

We know the camera’s built-in microphone records poor sound, but it does pick-up audio and that sound is excellent as a reference track for syncing to better quality sound takes on the set. As insurance, always make sure the camera’s mic is being used and is on automatic gain to prevent over-modulation.

A wide variety of microphones and audio accessories make it easy to create a backup audio track.

A wide variety of microphones and audio accessories make it easy to create a backup audio track.

Then insure your primary audio system is always backed up with a secondary system. If a boom operator is recording dialog and it is being recorded on digital recorder, make sure a backup is working along side it. It could be as simple as small lavalier on the same boom pole feeding a tiny backup recorder. Because every scene is difference, devise an audio backup plan on a shot by shot basis..

Let’s say a wireless microphone is being used on two principals walking down a path outdoors. Many things can go wrong with either wireless mic, including RF interference, dropouts due to distance, line-of-sight obstruction, dead batteries or even a broken cable. Don’t let such hiccups blow the take completely.

Rode app and SmartMic+

Rode app and SmartMic+

For backup, use a smartphone with a free recording app and a lavalier (turn on the airline mode to avoid incoming calls) or a small portable recorder in addition to the wireless mic. When done correctly, the backup device can overcome the dropout of the dialog. Digital audio recorders are now so small and low in cost they can be used to backup virtually any recording scenario.

Some small audio recorders with a shotgun mic can be mounted on top of the camera and used to record channels at full volume on one channel and at lower volume on a second channel for backup. Having a second audio track at a lower volume can save the day when sudden loud noises occur that cause distortion or clipping. This is known as a “safety track” and it can save the day during an edit session.

When using multiple cameras, each camera can have a high-quality mic mounted to the top of it as well as a master audio feed. With the multiple audio tracks, the editor can pull from the best sound for the shot.

Be careful in this scenario, as the differing distances of each camera to the subject will influence how the audio track sounds (the sensitivity and pickup patterns of the microphones are very important here). Even so, this setup offers multiple, viable audio recordings that the operator can fall back on in case the main audio source has problems.

If the sound operator is at an event where a live sound setup is used, ask the board operator for a feed. He can give you an auxiliary output from the sound board, via either a wireless or wired connection. This option offers good quality sound from a totally different backup source in case the primary source fails.

Red Giant Plural Eyes 4.0

Red Giant Plural Eyes 4.0

All of these primary and backup sound sources can be synced using a video editor or a standalone application like Red Giant’s Pluraleyes 4.0 ($299). With a touch of a single button, PluralEyes analyzes the audio from your cameras and audio devices and automatically syncs them up. No clapboards or timecode are needed.

On long audio clips, sound and video can sometimes stop matching up perfectly. If a drift is detected, PluralEyes automatically fixes it, and gives users the option to toggle between the drift corrected sync and the original audio without correction applied.

The key to have a secure backup sound source of a video shoot is to create one. Think in terms of a primary sound system and a Plan B backup for every scene. This way it will be rare when a re-take is needed on any sound you recorded. 

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