FCP single frame crossfade?

[Eric Toline]

In what? As long as the track stays in sync then I would say no.

Eric

[Jean-christophe Boulay]

That’s a mighty short crossfade! It can make a difference with a click caused by an audio region being cut wrong, as one frame is still 1600 samples. If you don’t have any clicks and are trying to smooth a transition, one frame is much too short. Clicks are best dealt with using fade-ins and fade-outs on the offending region, rather than a crossfade, anyways.

IHTH

JC Boulay
Technical Director
Audio Z
Montreal, Canada
http://www.audioz.com

[Jordan Wolf]

As long as the fade happens at a zero crossing, there shouldn’t be any click problems.

Wolf
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[Craig Jurkoic]

Thanks for the answers.
I’m not an audio expert. In summary I’ll take your answer as: “No, a 1 frame crossfade is meaningless unless there’s a click.”

In FCP I’m working at 16 bit, 48khz.

Two follow-up questions:

1. What’s “a zero crossing”?

2. If one frame is virtually meaningless, what is the smallest crossfade you would use in such a timeline? 2Fr? 3Fr? That is what’s the smallest practical crossfade?

Thanks, gentlemen.

[Ty Ford]

Hello Craig and welcome to the Cow Audio Forum.

After the smart answers given by others here, I’ll ask a dumb question.

Why do you want to do a 1 frame audio crossfade?

Assuming 30 fps that’s 1/30 of a second. If you’re doing 24 fps, it’s obviously 1/24 sec.

Regards,

Ty Ford

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[Terry Mikkelsen]

1. A zero crossing is in reference to the waveform of your audio and how it starts and stops. The easiest way to envision it is to think about a sine wave. It starts at zero, gently rises up to 1, then goes down to -1 (crossing zero along the way), and finally goes back up to end at zero. In theory, you want each piece of audio that you edit to start and end at zero so when butted up to each other, they match. Otherwise, to abruptly jump from one value to another value within a few samples will cause the audio (and speakers) to violently try and achieve this unnatural edit, causing a click, clack, chunk, or other unwanted noise.

2. The smallest x-fade to use is to use your ears. The piece may not require a fade at all. On the other hand, 15 frames maybe way too short for another piece. Its mostly feeling and interpretation, with a little technical limitations here and there.

Tech-T Productions
http://www.technical-t.com

[Craig Jurkoic]

Thanks Ty. Good question.
I don’t;
I don’t want to do a 1 Fr crossfade.
I’ll explain.
I’m currently working on an edited project deemed exemplary by a nationally recognized digital media education / training company. The project includes lots of 1 Fr audio crossfades. I do not understand their value.
Since I don’t want to assume they’re editors are mistaken ( This company has access to the most knowledgeable editors on the planet ) I figured I’d ask you guys.
Does that make sense?

-Craig

[Craig Jurkoic]

Thanks, Terry, for your explanation of a zero crossing.

[Ty Ford]

Terry’s entirely right, Craig, but the client is doubly always right.

A 1fr xfade may sound bad for content or zero crossover reasons.

If you can do ’em and it doesn’t click from a zero crossover error and the edit sound sound like c**p, then I guess you do ’em and ask, “May I have another?”

Regards,

Ty Ford

Want better production audio?: Ty Ford’s Audio Bootcamp Field Guide
Watch Ty play guitar

[Peter Groom]

Im not convinced its even possible 9let alone desirable).
FCP like all NLEs (avid etc) only allows manipulation +oe – 1 frame. You have to tell it if the fade starts at the transition, ends there or crosses it. Whatever way, telling it to do a 1 f tx means saying here we are on frame 4- by frame 5 have transitioned. Thats a CUT!
I think it will have a minimum of 2 to satisfy the criteria for a cross fade.
I remember my AMS Audiofile used to put a really small (a few ms) on every cut to stop clicks.

Peter

Peter