Convert AU to M4A
Convert AU files to M4A format online for free. No upload required, 100% private.
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AUM4ASize Reduction
Converting from AU (Uncompressed) to M4A (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- • Outdated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 M4A
M4A
MPEG-4 Part 14 Audio
M4A is an audio-only MPEG-4 container format, commonly used by Apple devices and iTunes. It typically contains AAC or ALAC encoded audio.
Extension
.m4a
Developed By
Apple Inc.
Released
2001
Compression
LossyTypical Use Cases
iTunes musicApple devicesAudiobooksPodcasts
Pros
- • Better quality than MP3 at same bitrate
- • Good Apple ecosystem support
- • Supports chapters
Cons
- • Less universal than MP3
- • Some older devices incompatible
- • Requires specific codecs