GSM 06.10 is a lossy speech codec used in GSM mobile phone networks for compressing voice calls into low bitrates.
Sun AU is the native audio format for Sun Microsystems workstations, using simple mu-law encoding or uncompressed PCM.
Go with GSM when mobile voice, legacy phone recordings, voicemail is on your mind. Its efficient encoding keeps things lean without sacrificing too much quality.
When legacy unix audio, sun workstation sound matters most, AU delivers. Its pristine output guarantees professional-grade results every single time.
Learn more about GSM and AU formats in our detailed guide.
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GSM (GSM audio) - GSM 06.10, lossy speech codec used in mobile telephony. Best for mobile voice, legacy phone recordings, voicemail.
AU (AU audio) - Sun AU, legacy Unix audio format for Sun workstations. Ideal for legacy unix audio, sun workstation sound.
Yes, GoConvertFile offers free conversion of GSM to AU for files up to 100MB. No registration required.
Most GSM to AU conversions complete within seconds for standard-sized files. Larger files may take longer depending on the conversion complexity.
AU is ideal for legacy unix audio, sun workstation sound. Sun AU, legacy Unix audio format for Sun workstations
No, converting GSM to AU does not cause additional quality loss — AU uses lossless compression. However, any artifacts already present in the original GSM file will persist in the AU output.
AU files are typically 2-5x larger than equivalent GSM files because AU preserves all pixel data. This is expected and necessary for lossless quality.