Directly supported audio formats:

Microsoft non-standard GSM 6.10 8 kHz, Mono (default)

Standard GSM 6.10 8 kHz, Mono (special request version)

Converting Existing Audio Content to GSM 6.10 8kHz

How do I use the Windows Sound Recorder to convert files to GSM 6.10 8kHz?

To convert PCM-encoded WAV files (among others) to GSM encoded WAV files, use the Microsoft Sound System in Windows.

In Sound Recorder:

1. Select Open from the File menu. Select the desired WAV file, and click OK.
2. Select Save As... from the File menu.
3. Click Change to display the Sound Selection dialog box.
4. Select GSM 6.10 from the Format list box.
5. Select 8 kHz, Mono from the Attributes list box, and click OK.
6. Specify a new Filename, if desired, and click Save.

What other ways can I edit and convert to GSM files using Windows?

You can use Sound Recorder in Windows to perform simple editing tasks, such as cropping the beginning or ending of a file. However, if you are using Cool Edit, available from Syntrillium Software, with Windows, you can open, play, and visually edit GSM files without having to edit the original PCM .wav file and then re-convert.