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Re: [ARSCLIST] Dolby B in software

At 03:52 PM 4/18/2003 -0400, Aaron Z Snyder wrote:
Has anybody ever written the Dolby encode/decode algorithm in Windows-based

The question arose when a friend of mine told me about some orphaned Dolby
B-encoded tapes. These apparently are reel-to-reel and without calibration
tones. Granted, without the calibration tone, decoding of the tapes would be
pure guesswork. However, a computer-based program would at least allow
non-real-time experimentation so that a plausible reference level could be

I have approximated the Dolby B algorithm in CoolEdit Pro with poor results. I do not have the process specs and, as you say, without the calibration tone there is a major piece of guesswork but neither of those was fatal. Despite fiddling with the parameters, I could not get the dynamic compressor to match the Dolby in dynamics. Ultimately, I dusted off my external Dolby B processor and did it in analogue; it was easier and I persuaded myself that it was more accurate.

Mike mrichter@xxxxxxx http://www.mrichter.com/

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