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Creating U-Law CCITT files for phone systems

I use Logic X for nearly all the production work at YoPo Music. However for some lesser well known file conversions Audacity is a free programme that can be really useful.

[box] Some phone systems need audio files converted to u-law (aka mu-law – a companding algorithm used in telecommunication applications) and Audacity can do the conversion for this kind of file requirement.[/box]

To convert an ordinary WAV file to u-law CCITT 8 Hz mono in Audacity, this is the method I use.

    1. Open the WAV or other format file in Audacity
    2. Set your project “rate” to 8000 Hz (bottom left hand corner of window)Project rate
    3. If you have a stereo file then to convert to mono click the drop down menu in the track header and choose “split stereo to mono” then delete one of the 2 mono streams (see pic)Split to mono
    4. Then to save your new file go File/ Export/ click “other compressed formats”,click “options” and choose “WAV (Microsoft)” as Header and “U-Law” as Encoding.