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How to "resolve" your digital audio using a PC

What still requires a device like our Micro Resolver to resolve analog audio cassettes to film or video can be done quite easily using a computer for the newer digital DAT tapes or Mini-Discs.

The reason is, DAT and Mini-Disc recorders have a very precisely controlled transport speed. They must have in order for them to work correctly. Because of this innate ability to maintain a relatively constant playback speed the only thing the computer has to do is make an overall, one-time adjustment to the length of each invidual "take". Once you have applied this correction to each of your wave files, you can import them into your video editing software and place them on the time line. They will all be in sync with the film you have transferred at 23.976fps.

If you already have an audio editing program, you may have the required functions you need. Check the software manual to see if you can apply a speed correction in .1% increments. If not, you may need to purchase a small audio editing utility like Goldwave (www.Goldwave.com).

Using your existing program or using Goldwave you must correct the speed of each the wave file downwards by the required 1/10 of 1 percent (-.1%).  

Using Goldwave, here is how to do it:

Go to >Effects >Time Warp >Speed and input the factor of ".999". Press "OK".

The wave file will be downconverted in speed by -.1% (negative 1/10 of 1%) and will now be in sync with your telecine transfers done at 23.976.

Notes:

This procedure does assume you have had your film, which was originally shot at 24fps, transferred on a flying spot or CCD telecine at 23.976fps. If you had the transfers done on a conventional film-chain using a telecine projector running at 24fps (with a crystal controlled or synchronous motor), this speed correction is not required. You can simply dump your wave files into the computer and place them, as in, on the time line. If you normally shoot at 25fps you do not have to do the speed correction, either.

If you are a MAC user, you can still use Goldwave but you will have to export your files to a PC as either WAVE or AIFF-C for Goldwave to work with them.