Audio Drift - Marantz 661 External Recorder

[Dave Mercer]

Recorded a few interviews the other day and have discovered something very odd. When trying to synch up audio from the camera with audio from the external recorder I get a pretty serious progressive audio drift from the recorder. I haven't had this issue on previous interviews and am wondering what has changed.

What is most troubling is that after synching with pluraleyes, the audio waveforms match up perfectly, but the audio from the Marantz don't actually match the Marantz's waveforms as seen in FCP's timeline. Audio synchs initally but drifts as the interview continues.

Using Panasonic GH2 (hacked) N American version filming in 50i.

Any ideas?

[Battle Vaughan]

Just a stab in the dark, but the hacked NTSC camera at 50i....hmmm, is it possible it's the camera that's drifting and not the recorder? That sounds as if it might be the variable in the equation....?

[Gary Nattrass]

They are two non syncronous sources running totally wild and independant of each other with no sync reference or timecode so they will drift, Battle is also right a hacked NTSC camera trying to bodge 50i is probably worse than the recorder!

To get pro synced sep sound you need pro gear with a common timecode or sync reference between the camera and sep recorder!

Some people may get away with it on some set-ups as the clock chip and sample/frame rates may be close enough for certain work but all non synchronous sources will drift to a certain degree over time.