Videomaker – Learn video production and editing, camera reviews › Forums › Technique › Sound › audio out of phase???
- November 8, 2006 at 4:07 PM #41157SRSFILMSParticipant
i have just had my first production for tv (5minutes) rejected because the audio was out of phase but i can find no problem when i listen to the project on the time line ( i edit with premier pro v7) or when i export to dvd (i have played this on a real expensive kickass home theatre system $100,000.00 worth) and the audio is great. i then exported the production to tape then recaptured it to premier and still had no problem. could anyone give me some advice here. camera,canon gl2. audio via ma-300 connector, balanced xlr cable and good quality mic. voice over via sony u :-// wcp1 wireless lapel mic. music mp3, all mixed to broadcast standard (-10db) mini dv tape. as i do not have a dv deck i export to tape using a canon mv700i video camera to save the heads on the gl2.
- November 8, 2006 at 5:03 PM #175283SRSFILMSParticipant
thanks for your quick response. yes i have played the copy tape on the good system and it was really good.to expand a bit i also upload using the small canon not the gl2. the tv station sent me a dvd copy of what i sent them and it sure sounded tinny. i’m sorry but i don’t know how many frames out they think it is but to me there’s no problem, this is whats so confusing. i suggested to the tv company (very nicely and tactfully) could it be a problem at their end and they were SOOOO OFFENDED. no there’s no one at the tv company who wouldn’t want my stuff playing, i’m a full time surfing vid producer at one of australia’s best surf breaks so they want my productions as much as i want to show them. maybe if you went to my youtube channel and listen to the audio on some of my clips as i have done nothing different there to what i sent to tv you may be able to advise me from there http://www.youtube.com and the type in "the superbank news" into the search box if you have the time 😀
- July 16, 2014 at 6:45 PM #210786lonejakylParticipant
I realize this is an old post….not sure if you ever had a response to the issue so I thought I'd try to help. What the TV station is refering to by "out of phase" is not a "sync" problem, meaning the frames should not be out of sync with the audio. What they are referring to is audio issues with the L/R or frequency spectrum of the audio being out of phase – as in sine waves phasing polarity to cancel out certain qualities of the audio. This usually happens on the low end first which results in sound qaulity that sounds like is coming through an telephone from the 1920s.
If you sum your audio master to Mono and the sound quality (low, mid, high) characteristics change, you have "out of phase" audio. Another test is, use an audio mixer that has balance (L/R) pan controls on each channel, connected from your master output to another unit to record, like a tape recorder, etc. On the mixer make sure you have the left channel & right channels connected to their own input – such as Left on channel 1 & Right on channel 2 and ch 1 panned left, ch 2 panned right. Your sound from the mixer should be stereo to when listening (different characteristics in the left vs. right). Now pan both ch1 & 2 to center & listen for the audio characteristics to change when centered. If it does change and you loose qaulity, it means your Left/Right channels are out of phase with each other. If you've already been using a mixer to record your master output with Stereo – it's also possible that one of your connectors has the polarity reversed, forcing the signal to become out of phase, ie +/- vs -/+ rather than +/- vs +/-, etc.
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