Preparing an Audio Mix for Dubbing
TIPS AND TRICKS
Here at Boyde Studios, we can facilitate any type of project or file type but migrating sync’d files can be tricky. These tips will help provide the closest thing we have to a pain-free experience. In this document, we will look into troubleshooting, as well as our recommended file types for various use-cases.
Common file types
AAF
XML/OMF
Individual track export (our recommended)
Multi-channel video/discrete audio export
AAF
AAF was designed to migrate timelines from editing software to colourist programs and for this it’s often a necessity. When it comes to audio, we don’t have quite the same needs. Therefore, we don’t recommend this approach for most projects.
AAF often migrates with random errors and we end up using a lot of our time together troubleshooting rather than mixing. This is because each editor (Adobe, Da Vinci etc.) codes the file type in a different way. The result is you find sometimes it works and often it doesn’t.
Sometimes AAF is warranted but check in with us in advance on the editing program you use and what the deliverables are and we will help you through whether AAF is the right format for the project.
Some best practises for a successful AAF are to:
Consolidate/render audio where possible
Delete any inactive/muted audio files/tracks from the session
Do not embed the AAF into the video (unless using Avid MC)
Visit the internet to find best settings for your editing software
XML/OMF
XML & OMF are very similar to AAF but they work better/worse with varying programs.
The differences are that XML doesn’t contain audio and won’t render any effects you’ve done - it’s simply a file pointing mechanism. It’s also more closely associated with Final Cut then other editors and therefore, tends to work best from that software.
For the same reasons as AAF, we tend to not recommend this method. If you do intend to use XML or OMF, make sure to consolidate beforehand as it can get confused if files aren’t named correctly.
Track AUDIO export
This is the format we do recommend. The aim with this method is to individually export each audio track as it appears in your timeline. The list of which can look something like:
VO
Diegetic 1
Diegetic 2
Music
Sound FX 1
Sound FX 2
This is the only full-proof way to successfully migrate sync’d audio so that what we receive is identical to your project. Better still, you only need to send us a few audio tracks so it uses very minimal data making the process much faster to share.
Preparing for Track Export
Because we’re working with consolidated audio, our goal with the prep is to retain flexibility for us here in the edit.
1) If you have any audio regions (within a group) that overlap, then place on separate tracks and name appropriately. See Fig.1 for a common example where we have two music regions. Do this as many times as needed. With layered SFX, this may mean multiple tracks. Note: If you aren’t certain about something then just leave it messy, we can always sort our side.
2) Visit Page 10 of this document and follow best practices.
3) Export your tracks individually (Foley 1, Foley 2 etc.), using the criteria on page 9. Your video editing software may have a speedy way of exporting audio tracks in one go, otherwise you can solo [S] individual tracks and export one at a time. All exports must start and end at the same point.
4) Export a low-res (720p) version of your film that we can reference using the same start/end points.
You do not need to send us any individual project files like the AAF/OMF methods. In the rare event we need the original part, we can ask. Thats the beauty of this system, you generally only send us a few audio files and get one audio file back in return, mixed and mastered.
Discrete audio/multi-channel
What does ‘Discrete’ mean? Discrete audio is simply individual audio tracks inside a multi-channel project. The previous option, ‘Track Exporting’, is different from this approach because that focusses on the most common editing style, which is that you have your audio outputting to Channels 1 & 2 (Left/Right). Multi-channel projects are those setup in advance, within your editor, that have multiple output channels. For example, Dolby 5.1 has 6 output channels. It can also be used so that any multi-channel video automatically exports with separated tracks attached. E.g. Lav outputting to Channel 1, VO outputs to Channel 2, etc. As long as it’s all named correctly, we can receive this in a similar way to ‘Track Exporting’
essential SETTINGS
To begin, there are some export settings that are universal.
Standard delivery will be a sample rate of 48000 (48k) with a bit rate of 32-bit Float. 24 Bit is also fine. Occasionally, a project may have demanded a recording sample rate higher than this but do not upsample.
The codec should be Uncompressed with a format of Broadcast Wave (WAV).
We require a separate 720p film (with audio on) that we can use as a reference.
All audio exports and reference films must start and end at the same point.
Best practises
The aim of the mixer is not to re-create all the great work you’ve done but simply take it and improve upon it.
Keep your session neat and tidy from the beginning in case we need to troubleshoot.
Check that any multi-channel camera tracks have been appropriately split and named - these can often be hidden from view! It’s very common to have the Sony FS7 contain one track from a lav, a boom and additionally, the cameras on-board (which we often don’t want).
Reduce the level of all individual audio tracks (simultaneously) so that the output isn’t peaking into the red (ideally peaking around -6db).
In-audible cross-fades are required on most audio regions to stop any project created clicks & pops. Fades of 5ms and above will counter-act this anomaly.