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Can analog audio synch with video


Christopher Frey

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It's not a dumb question at all. Many would just assume yes and move on at their own peril. Truth is...ANYTHING that works on a motor mechanism like an analog cassette recorder, film camera, etc. will not be guaranteed to keep sync unless you using a quartz crystal oscillator for obtaining the frequency that drives the motor. The quartz crystal is extremely precise...that's why clocks use them. Cassette recorders do not generally use crystal oscillators to obtain operating frequency. Therefore the method of using these synced was to either use a crystal sync pulse generator on the other track while syncing the (usually film device) or to use a cable to hook up between the camera and the cassette deck if the camera had a pulse generator and then use a resolver in post to speed up and slow down the audio to match or "resolve" the frequency of the camera. Since you mention using a video camera, your frequency is set at 60Hz for NTSC or 50Hz for PAL. So if you want to sync, you'll have to have a crystal sync 60Hz (or 50Hz) pulse generator for one of your stereo tracks and have it resolved in post. Then you can sync up both tracks perfectly.

 

I hope this has helped you. If it sounds like too much to go through, just use a digital audio recorder that has a fixed frequency.

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Thanks... that was helpful. If I were to do it in post what would you recommend for software and would you know or have an idea of how I would go about doing that? I am new to sound and it's what I most nervous about when it comes to my short.

 

Thanks.

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Thanks... that was helpful. If I were to do it in post what would you recommend for software and would you know or have an idea of how I would go about doing that? I am new to sound and it's what I most nervous about when it comes to my short.

 

Thanks.

 

If you still plan to use the Marantz Cassette recorder and also want to resolve it yourself instead of paying lab fees, I would recommend a micro resolver from The Film Group. Here is the link to the item you would need:

 

http://users.aol.com/fmgp/sync6.htm

 

Otherwise, you can do it the painstaking way which is to compress and expand audio clips by eyeing them and constantly previewing them (which eleminates Premier as one of your editing options since Premiere is ehh about previewing) until they seem to sync enough to pass. I have done this and I recommend editing using Pinnacle Studio to do the audio first to get it synced (they have a very easy to use audio timeline and can preview in real time) then outputting the edited audio to an AVI and then going into Premiere for the heavy duty video editing. Regardless of what I do, I always use Pinnacle for audio and then Premiere for the heavy editing. If you want a package that does both well, I would honestly recommend the Europian made Magix editing suite. It's better than it's low price tag would lead you to believe. Unfortunately, it also has a steep learning curve.

 

PS- In all good conscience, I should tell you about a technique that tends to work pretty well for most. Regardless if you have a non-crystal synced camera or a non-crystal synced recorder, you can do a "double slate." What this means is that you use the clapper board at the beginning of the take and also at the end of the take. When you get into post, you expand or compress the clip until both the beginning and ending slate match up. It may not sync everything in between perfectly, but usually it works out to be very passable. Might be worth it if you're on a seriously tight budget.

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