There are tools that change the "tempo" of audio.
This changes the speed, but keeps the tone normal; not like "chipmunks" speedup that increase the frequencies. So it sounds like the narrator is speaking naturally, just faster, which is often useful. You can save over 2 hours on a 10 hour book at 1.3x speed.
Many audioplayers, like "Smart" on Android, let you adjust playback speed on the fly.
But if you want to make new set of files at a higher (or lower) speed, you can use
fre:acFre:ac HOW TO CHANGE TEMPOYou store groups of settings in configurations, so you can then choose that option and not have to fiddle with each setting again.
- Options/Active "New configuration"
- Options /General settings
- Change the configuration name to e.g. "speedup"
- Encoder: prob default is LAME MP3. If you like that, go to the button next to it "Configure encoder" to choose the rate to make the output file.
Preset "Medium" if you don't have any preference. You can make M4B if you prefer (see here for details). - Processing -- tick "Enable signal processing"
- Components: select "Rubber band tempo pitch changer", click arrow to move to "Selected" on right.
- Select that and you have the tempo settings. Most important is speed. Try +30% or whatever you were using before. Other settings, leave as default. Though if you have a normal audiobook narration, not a dramatized one, choose "stereo processing" as "combined" since it's really mono.
- Back out with "OKs" until you get to the main screen. Now drop in tracks and click the big triangle button to start encoding.
Just do one track to check if you like the results. Go back to the settings to change the speed or the MP3 settings.
Once you're sure the settings are what you want, you can drop folders of files and convert them en masse with a single click to a new set at your new tempo.
You can create multiple configurations, each with a different speed, then just choose the "active configuration" before encoding.
