Zoom's H4N can vary speed of audio that it records, but often has trouble doing that to podcasts (from CBC, etc.). Is there a way to persuade it to work with nearly "any" MP3?
If not, what FOSS software can do the job?
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Sign up to join this communityZoom's H4N can vary speed of audio that it records, but often has trouble doing that to podcasts (from CBC, etc.). Is there a way to persuade it to work with nearly "any" MP3?
If not, what FOSS software can do the job?
I'm not sure why you are having trouble stretching audio on your Zoom, but it may have to do with the fact that MP3s are compressed and the Zoom may have trouble manipulating compressed data. You may have better luck with uncompressed audio like WAV files.
Audacity is a great place to start. Although 1.3.x is in beta, I've found it to be very stable and a lot more powerful than 1.2.x. You will want to convert your MP3s to an uncompressed format like WAV before you start stretching.
If you want to get really crazy, give PaulStretch a try. If you are looking for something with more of a mid-90s sound, take a look at AKAIZER.
I always get best results using raw wav files and encoding later. It's just easier all round - you end up with better quality sound as well, as you are only compressing/encoding once.