input file : source soundfile
output file : source soundfile
processing mode : global
You can use this option to change the speed at which a soundfile is played back. Since the system just modifies the file header (all signal samples remain unchanged) speed adjustments can quickly be made.
Many sound cards allow you to precisely tune the sampling frequency over a wide range of speeds - even though the recording rate is usually limited to a certain number of standard frequencies. Should the card be unable to support a declared playing speed the system will issue an appropriate message each time you attempt to play the corresponding audio file.
Speed adjustments can serve different purposes. Since speeding up an audio file raises the pitch and slowing it down lowers the pitch you can make someone sound like Donald Duck or you can make your poodle sound like a bulldog. But seriously ... speed adjustment is a very useful tool should you have to deal with audio material recorded or played back at nonstandard rates (check also Adjust RPM rate ).