How to Use iTunes to Make a Smaller MP3 File
- 1). Add the MP3 file to your iTunes library if it isn't already present. Drag and drop the file from an Explorer window or the desktop into the iTunes interface, or use the "Add File to Library" feature in the File menu to find and select the file on your disk and add it.
- 2). Check the current compression level of your MP3 file by right-clicking it in iTunes' music list and choosing "Get Info" from the drop-down menu. In the window that appears, read the "Bitrate" and "Sample Rate" fields in the "Summary" tab. These are two essential parameters of the file's compression level.
- 3). Decide on a bitrate to compress the file with. The lower the bitrate, the more disk space you'll save. One hundred twenty-eight kbps is commonly considered the minimal bitrate required to preserve the fidelity of music, but recordings of speech may be compressed even more.
- 4). Decide on a sample rate to compress the file with. Like bitrate, lower sample rates also reduce file size at the expense of fidelity. The sample rate used in CD recordings is 44.1 kHz, and it is the most common value for MP3 files.
- 5). Click the "Edit" menu, then choose "Preferences." A new window appears.
- 6). Click the "Import Settings" button. A new window appears. Choose "MP3 Encoder" from the "Import Using" drop-down menu. Choose "Custom" from the "Setting" drop-down menu. The "MP3 Encoder" window appears.
- 7). Specify the bitrate and sample rate you chose in their respective drop-down menus. Enable the variable bit rate, or VBR, check box. Choose "Mono" from the "Channels" drop-down menu if you're willing to sacrifice the stereo separation of the recording. Click "OK," then click "OK" again to close the "Import Settings" window. Click "OK" to close the Preferences window.
- 8). Right-click the file in iTunes' music list, and choose "Create MP3 Version" from the drop-down menu. The progress of the conversion is displayed in the play area at the top of the iTunes window, and a chime sound plays to indicate completion of the conversion.
- 9). Double-click the converted file, which appears in iTunes' list beneath the original, to play it and listen to the quality. Right-click it and choose "Get Info" to check the file size and to see how much disk space you've saved. Right-click it and choose "Show in Windows Explorer" to reveal the location where iTunes stored it.
- 10
Remove the original file from your iTunes library, and delete it from your computer only if you're satisfied with the quality of the smaller version. Unlike other compression formats such as ZIP, a compressed MP3 file can never be uncompressed, so once you've deleted the original, you're stuck with the more compressed version.
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