How to do Speed Correction in Audacity
- 1). Click "Open" on your Audacity menu bar along the top of your screen and select "Open." Use the navigation window to select your song or other audio file.
- 2). Highlight the portion of your song that requires correction. Your song file appears as a horizontal region spanning across your Audacity window, with the time line directly above. To highlight a portion of the song, drag your mouse over that part of the region (it will turn dark blue). To highlight the entire song, click Ctrl+A, or Command+A, if using Mac OS X.
- 3). Click "Effect" on your menu bar and select "Change Speed" from the drop down menu. A new window will appear with a horizontal slider, indicated by the words "Percent Change."
- 4). Drag the slider to the right to speed up your selected audio. Drag the slider to the left to slow down your selected audio. As you drag your slider, a number will appear in the "Percent Change" box. For instance, if the number reads "10.000," your audio region will play 10 percent faster. If the number reads "-20.000," your region will now play 20 percent slower.
- 5). Click "OK" when you select your desired rate of change. To ensure that the change is adequate, press the green "Play" button on your Audacity window and listen to the file. If the speed does not work for you, click "Edit" on the menu bar and select "Undo Change Speed" from the top of the list. Try your operation again until your speed sounds perfect.
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