Convert AU to M4R
Convert AU files to M4R format online for free. No upload required, 100% private.
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AUM4RSize Reduction
Converting from AU (Uncompressed) to M4R (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
UncompressedTypical Use Cases
Unix/Linux systemsLegacy applicationsSimple audio storage
Pros
- • Simple format
- • Unix native
- • Lightweight
Cons
- • Outdated
- • Limited features
- • Poor cross-platform support
About M4R
M4R
iPhone Ringtone Format
M4R is the ringtone format used by Apple iPhones. It is essentially an M4A file with a different extension, limited to 40 seconds for ringtones.
Extension
.m4r
Developed By
Apple Inc.
Released
2007
Compression
LossyTypical Use Cases
iPhone ringtonesiOS alert tonesCustom notification sounds
Pros
- • Native iPhone support
- • Easy to create from M4A
- • Good audio quality
Cons
- • iPhone only
- • 40 second limit
- • Requires iTunes for transfer