AAF handles explained
How much audio should you send beyond each cut? Too little and the sound editor calls you back for the rushes. Too much and you hand over a file nobody can move. Here is how to decide.
What a handle actually is
When you cut a clip in Final Cut, the material either side of the cut still exists in the source file — you simply stopped using it. A handle is a slice of that unused material, carried into the AAF before and after each region.
It is what lets the sound editor pull a transition open, cross-fade into the next line, or catch a breath that got clipped — without asking you for the rushes and without touching your edit.
Without handles, every region ends exactly at the frame you chose. Any change means a new export, a new delivery, and a new day.
How much to send
By genre
- 2 s — fast-cut magazine, news, corporate. Enough to rebuild a cut, small enough to email.
- 5 to 10 s — documentary. Room to breathe on interviews.
- 10 to 30 s — drama, feature. Transitions get genuinely reworked, and the sound editor needs material to work with.
What it costs
- Handles are embedded twice per region — before and after — and on every mono track the region produces.
- Measured on a real project: going from 2 s to 30 s took the AAF from 0.54 GB to 1.63 GB, three times the size.
- AAFx shows the estimate past ten seconds, before you commit.
The rule that never fails: ask the person receiving it. Handles are the one thing sound editors always have an opinion about, and it takes one message.
Handles do not move your audio
A common worry, and a fair one: if you add material either side, does everything shift?
No. The region still starts and ends exactly where you placed it on the timeline. The handle sits inside the embedded essence, available but not played, and the clip declares where in that essence the audible part begins.
We verified this by comparing two AAFs of the same project, one at 2 s and one at 30 s: 168 region placements, zero difference in position or length. Only the embedded audio grew.
When a handle comes back short
A handle can only use material that exists. If a clip starts three seconds into its source file and you ask for ten, you get three — there is nothing before it.
This is normal and not an error. What matters is that the converter trims what it declares: an AAF announcing more material than it carries makes Pro Tools read past the end of the essence, which produces saturated noise. AAFx shortens the region rather than lying about it, and tells you which clips were affected.