Convert AU to AMR

Convert AU files to AMR format online for free. No upload required, 100% private.

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AUAMRSize Reduction

Converting from AU (Uncompressed) to AMR (lossy) will significantly reduce file size. Some audio quality will be lost, but the difference is often imperceptible at higher bitrates.

About AU

AU

Sun Microsystems Audio

AU is a simple audio format originally developed by Sun Microsystems for Unix systems. It supports both compressed and uncompressed audio.

Extension
.au
Developed By
Sun Microsystems
Released
1980s
Compression
Uncompressed

Typical Use Cases

Unix/Linux systemsLegacy applicationsSimple audio storage

Pros

  • • Simple format
  • • Unix native
  • • Lightweight

Cons

  • • Outdated
  • • Limited features
  • • Poor cross-platform support

About AMR

AMR

Adaptive Multi-Rate Audio Codec

AMR is a speech audio codec optimized for voice recording. It is commonly used in mobile phones for voice memos and MMS messages.

Extension
.amr
Developed By
ETSI
Released
1999
Compression
Lossy

Typical Use Cases

Voice recordingMobile phone audioMMS messagesVoIP

Pros

  • • Very small file size
  • • Optimized for speech
  • • Mobile device support

Cons

  • • Poor music quality
  • • Speech only
  • • Limited compatibility