ZOOM H1 can`t sync

[ThePuppy]

Hello, recently bought myself ZOOM H1 recorder. First I was happy as a clam but later I found that ZOOM skips sound and I cant sync it with video. Also it records very quiet + audio spectrum is very short so its hard to sync. What can I do? How to fix this problem? I even recorded video to show this problem - https://youtu.be/Ql0YuxkcaGk (start watching after 0:44)

[mike20021969]

If you listen to the recorded file on the ZOOM H1 via it's headphone socket, does the audio skip?
If it doesn't skip, then it's a problem after importing the audio file into Vegas.
If it does skip, you must have a faulty ZOOM H1.

[filmboss80]

I would first suspect a faulty SD card. You should also manually adjust your volume controls.

[turk690]

....but later I found that ZOOM skips sound and I cant sync it with video....

The problem is not with the Zoom, but is common and expected when separate devices not connected to each other in any way are used to record audio and video of the same scene at the same time. The small microsecond differences in the accuracies of the time-keeping sources in each device build up and accumulate, so what was sync'd at the beginning of the clips is not anymore in the middle or end, and vice versa, on playback. Some devices are more accurate (with respect to each other) such that an hour's worth of video and audio can successfully be sync'd, and be off with each other by, say, only 5 frames (too little to be perceived). On the other hand, if a device pair record material that is off in between them by 5frames a minute, for 25fps, after 5mins, there will be a second's worth of difference between the audio and video clips produced, which is obvious. In a professional situation, a common sync signal is generated and used by all the audio and video devices recording the scene, and since this timecode is absolute for that session, editing and syncing audio and video is a snap.
On the other hand, some amateurs like us may use a common sledgehammer approach to this problem, which is to find the absolute lengths of the audio and video clips, then compress or expand (temporal, not dynamic range) the audio so that it becomes in sync with the audio throughout their lengths. The approach I prefer involve identifying parts of the audio that have quiet stretches or the sound is rhythmic (like traffic or flowing water), then cutting the audio clip at those parts so that the whole audio clip is broken down into chunks of 1 to 5 minutes, then syncing each chunk as best as you can to the video at that point. You can also cut the video in chunks instead and sync to the audio, as in my case below.
Before you start recording, you have to have a fair idea of how much difference there is in the sync between the audio and video devices you use so you can use that as a guide in cutting the audio (or video) clip should you follow my method.
For example, I use a Zoom H2 and H2n and a Canon XA10. In between the Zooms and the Canon, if I record for 15minutes with the Canon at 24p, there is a sync difference of about 6frames between the clips, which is a noticeably glaring 250ms. The Canon produces 7 to 8min long AVC clips at the quality and resolution I have chosen, and makes it convenient for me to move these chunks along the timeline to sync with the audio.
If you researched on the web about this issue, you might have come across PluralEyes, which sounds nifty, but is useless in our case. What it will do is sync the exact middle of the clips, leaving the beginnings and ends still sorely out of sync; clearly it can only be used in cases where absolute or general sync was used, or an audio and video device pair used to record the clips had such a small difference in their individual accuracies (nanoseconds, maybe?)

...Also it records very quiet + audio spectrum is very short so its hard to sync....

Have you tried bringing up the recording level on the Zoom? The default recording level on the Zooms is a vague value of "100"; you can increase it, then choose to enable a limiter to prevent distortion should recording levels jump at or above 0dB (not so familiar with the H1 so I imagine it has similar controls to H2).

[smrpix]

Quick minor correction, Current version of PluralEyes can correct audio drift.

[turk690]

Quick minor correction, Current version of PluralEyes can correct audio drift.

I didn't know that. How does it do it? Stretch/compress the audio or?

[smrpix]

This is from their site. I tried it a couple of times, but never had confidence that it wasn't trying to change the timing on the video!

Sync> Correct Audio Drift
If the sync of an audio clip to a video clip is good in the middle of the clip, but is a bit off at each end, then the most likely cause is that the audio recorder's recording speed was not perfectly accurate. This is called audio drift. The Correct Audio Drift option will detect this problem and fix it.

When drift is detected in an audio clip, the sync is stopped. Drift correction is applied to all the audio clips on that track that need it and the sync is started from the beginning again. The drift correction process creates a new audio file for each original audio file. This new file is referenced when the project is exported.

Bins that containing drift-corrected media show a tan-colored badge. Drift-corrected media items have a tan-colored icon, and hovering over the icon shows the amount of drift correction applied.

Drift correction is on by default.