Jon Tatooles, the co-founder and managing director of Sound Devices in Wisconsin, has been thinking a lot lately about how to improve on the lackluster in-camera recording in most DSLR cameras that shoot video. The solution? That old standard, dual-system sound (known even longer as double-system sound). Tatooles says he’s seen a steady rise in dual-system sound on HD DSLR productions, thanks in part to the increasing numbers of Sound Devices field recorder and mixer customers who have been shooting documentaries, features and music videos with the Canon 5D and 7D. I asked him to share a few set up and workflow tips when using multi-track recorders to enable easier syncs and much fuller sound in post.

Q: When shooting HD DSLR video, what’s the most common-and avoidable-mistake people make when recording their audio?

JT: The first step to improving audio is to get the damn microphone off the camera! The best microphones, audio mixers, and recorders are no benefit if the microphone is positioned poorly. The right orientation for the camera is usually not the right location to position the microphone.

Microphones need to be positioned quite close to sound sources to increase the pickup of direct, wanted sound and to minimize indirect, unwanted sound. Unlike a camera lens, there is no such thing as a zoom microphone. Directional microphones may have good off-axis rejection, but they don’t zoom. Using either directional microphones positioned with a boom pole or lavalier microphones placed on the subject are fundamental ways of getting clean, usable dialog.

Q: Do you recommend using multi-track recorders in place of or in addition to the camera’s built-in audio?

JT: If the camera has audio connections, it is always a good idea to use them, even when also recording to a dedicated audio recorder. Think of the camera’s audio circuits as a basic two-track audio recorder. You won’t have the noise performance, frequency response, or control offered by even the simplest dedicated audio recorder, but camera audio provides a good backup and sync reference.

As the number of sound sources or actors in a scene increases, multi-track audio recordings give an editor more options. Placing a microphone on each of the sound sources allows the post production mixer to remix a scene later. That said, since the first days of sync sound films, sound on set was carefully mixed to one track. That still is the case today for single-camera feature work, even though multi-track is often rolled, “just in case”. A good production mix speeds editing and simplifies the entire production workflow.

Q: What’s the best set up when recording dual-system sound for optimal syncing in post?

When approaching dual-system DSLR-based shoots, you have to treat the camera just like a film camera. At the minimum, use a clapboard, or slate, at the head of each take. Its visual and audible sync cues gives the editor the elements needed to sync a take. A comprehensive written log of picture and sound will also simplify file organization.

In a timecode-based workflow, using a timecode slate, where a timecode value is jam-synced to the audio recorder, can make syncing faster than wild sync. As long as the timecode numbers on the slate are visible in frame, sync can be performed, even without an audible clap. Several Sound Devices recorders, including the 702T and 744T, are timecode-capable.

Sound Devices 702T Field Recorder

Once timecode is in use, it’s critical to know what frame rate the camera is running and ensure that sound is set to the same corresponding frame rate. If a rate, such as 23.98 is set on the camera, but a rate such as 24 is set on the recorder, the timecode will have a varying offset on each take, causing syncing problems in post. A mismatch in frame rate on the sound files can also cause sound and picture to drift in a software application such as Final Cut. Final Cut will pull up or pull down the speed of the sound file to match the frame rate of the session.

Q: Many people have been using Singular Software’s Plural Eyes plug-in to sync their sound to HD DSLR footage in Final Cut. Do you have any set up advice-or workflows to avoid-when using that plug-in with audio recorded on, say, a Sound Devices 722, or the 552
production mixer?

JT: Plural Eyes is pretty amazing. A clean scratch audio track recorded on the camera gives the application the best chance of being able to sync. Because Plural Eyes doesn’t use timecode for synchronization, non-timecode recorders such as the 722 or the 552 mixer are perfectly suitable in applications where Plural Eyes is used for sound and picture synchronization.

Sound Devices 552 Production Mixer

Q: Have recent firmware updates for the Canon 5D or 7D improved HD DSLR audio post in any way?

JT: DSLR cameras are designed for picture first and audio last. Their audio circuits are very basic compared to dedicated recorders, both in terms of control and audio performance. While firmware updates can provide additional controls and metering, firmware updates can’t change the analog circuitry which is at the heart of the camera’s audio performance.

Q: What’s still needed on the camera side?

JT: If camera manufacturers would provide a standard format digital audio input, such as AES or SPDIF, sound could be dramatically simplified and improved. With a digital audio input, external audio devices such as digital mixers, microphones, or wireless receivers could be directly connected; all analog-to-digital conversion could be handled outside the camera. These digital inputs are showing up on broadcast cameras, but their inclusion on DSLRs would make the sound recorded on the camera production-grade. But since firmware updates aren’t going to magically change the difficulty in getting great sound during production, using professional tools, such as Sound Devices mixers and recorders to provide quality audio signals to the DSLR camera is a first step. Recording dual-system audio onto a dedicated audio recorder is always going to provide more flexibility for the sound engineer than any camera audio circuit. Dual-system sound is something that will be with us for the foreseeable future.

Q: What have you heard about the sound capabilities in the forthcoming Nikon EVIL camera?

JT: There is a lot of technology in these kinds of cameras at the moment, but reducing size and price seems to be the motivation to increasing their market. These new mirrorless cameras are even smaller than the present generation of DSLRs. It’s hard to imagine that camera manufacturers have much room, or motivation, to focus on audio performance. While one camera may improve its audio versus its competition, dedicated audio recorders will always be more flexible and powerful.