Phase Issues inherent in Final Cut Timeline?

[Chris Walldorf]

I guess the major problem I see is whether or not there are phase problems inherent in Final Cut as I’ve had this problem with several different systems and multiple configurations. This surprised me and seemed more straightforward since it was 2 identical mono channels that sound fine in the camera but somewhere between digitizing and the timeline, they are thrown almost perfectly out of phase. I say almost because panned mono I can still hear something which means they aren’t perfectly out of phase. It’s definitely less noticeable with a lav and boom situation; so much so that a lot of people might not notice it. Obviously with two identical mono channels, the effect is most noticeable. I know how to fix it, but doesn’t this imply something funky with the audio engine or audio architecture of Final Cut? Couldn’t it completely screw up a stereo mix when you import back into FCP if it’s flipping the phase of one of the channels?

I don’t think I understand the difference between dual mono and stereo other than panning and linking and how that really changes anything. Isn’t dual mono just 2 mono tracks panned in the middle vs 1 stereo track (which is really 2 mono channels paned L and R?

[Jeremy Garchow]

[Chris Walldorf] “sn’t dual mono just 2 mono tracks panned in the middle vs 1 stereo track (which is really 2 mono channels paned L and R?”

Dual mono is two mono channels sent to two different outputs.

Stereo is a pair sent right and left.

[Chris Walldorf] ” I know how to fix it, but doesn’t this imply something funky with the audio engine or audio architecture of Final Cut?”

No, as you can easily fix this. When you monitor on your camera, how are you monitoring? Mixed or discreet?

[Michael Gissing]

Bottom line is there is nothing inherent in FCP to cause the sort of phase canceling you are talking about. You can’t flip phase on a channel in FCP so there is no chance you have a button set wrongly. Capture via firewire means straight digital path so again no chance of phase errors.

Problem must be at the mic, mic cable, mixer to camera or the camera itself. The problem must be happening in the analog domain.

The other possibility is a problem with the wiring on the Mac’s analog output.

[John Fishback]

I agree with Michael. I’ve never heard this happen with FCP. It’s got to be an external issue. Two channels being 180 degrees out of phase would be totally unacceptable in any audio device (unless it was a switched option as on a console strip).

John

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