Computers have been standard equipment in post production for some years now. Not all have real time operation systems so that latency can be a problem. When synchronizing the major problem is not accuracy but repeatability, it does not matter if there is a one frame sync error provided that there is always a one frame sync error!
Recently I was asked to add phase compensation to the P2MMC, Jun Yamazaki who works with Tac Systems (our Japanese agents) discovered that different DAW's had a different offset error when synchronizing to MTC. To measure offset Jun recorded timecode and looked at the recorded waveform, Jun is a timecode geek like me but this is not a suitable method for everyone!
I asked Chris Braclik (I worked with Chris when at Audio Kinetics) from Soundtrack Productions to make 3 stereo WAV files, each has one track with continuous timecode at 24, 25 or 29,97fps, starting at 00:59:55:00 and ending at 01:01:05:00. The other track has 1KHz bursts one frame long, once per second stating at 01:00:00:00 and ending at 01:01:00:00. The bursts are positioned exactly at the start of each second.
You can use these files to check the timecode latency and more importantly the repeatability of both record and replay.
I checked the Record on a Sadie system, there was a consistent 1/5 of a frame error when locking to LTC , I have not checked the playback yet.
I will publish a chart of your results if if receive enough information- DAW, Platform, and Results.
Click here to download the test files
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