-
Mysterious audio problem — channels canceling themselves out
I’m new to DVCAM editing and final cut pro and have had a really strange audio problem. On one tape I captured the audio levels were strangely low. I have two channels of mono audio. Channel one is audio from a mike used by an interviewee and channel 2 is audio from a mike attached to me asking questions.
I pulled up the audio mixer and found that if I moved both levels up together the sound remained very low. However if I raise one level and lower the other – whether I raise 1 and lower 2 or vice versa, then I have good clear sound at normal volume!
Then I found on another digitized clip, where audio had worked fine for days, that for one interview (my first one)the same problem appeared, but for all other interviews on the tape there was no such problem.
By the way, when I play the tape back on the deck, the audio sounds fine. Anyone got a clue on this one? Thanks!
-
3 Replies
-
My guess is that you have an audio phase problem somewhere. One of the channels is 180 degrees out of phase with the other channel. When you mix both channels together, they will cancel each other out. Even if the channels aren’t exact, which is what it sounds like in your case, there will still be cancellation problems. You didn’t say just where and how you are monitoring your audio, but look for an improperly wired connector either on the input or on the output to the computer or mixer if you are using one. The problem could have even been recorded that way in the field with a reversed connector somewhere. Double check all your wiring and I’ll bet you’ll find your problem.
Tom -
It’s a phasing problem. As you have two tracks of audio you won’t miss one of them so blow one away and make the one left mono.
– R
-
Thanks for the feedback! In tracing the problem I think it did happen in the field. I was easily able to fix it in FCP.
Cheers,
P
Reply to this Discussion! Login or Sign Up