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AU to MPEG-4 ALS - Online Audio Converter
Convert AU to MPEG-4 ALS online. Private, client-side - no uploadrequired. Batch conversion, quality presets, codec control.
Convert AU to MPEG-4 ALS
Drop AU audio here or click to select
AU
MPEG-4 ALS (MPEG-4 ALS)
About AU to MPEG-4 ALS
Convert AU to MPEG-4 ALS. AU is Sun's simple container, usually holding 8 kHz telephony audio. MPEG-4 ALS compresses PCM losslessly with random access. Few players open it; convert FLAC for sharing..
Why convert AU to MPEG-4 ALS?
- Larger files than lossy shares with MPEG-4 ALS lossless quality.
- Keep quality where supported.
- Private, no upload - runs in your browser.
AU vs MPEG-4 ALS
| Codec | PCM 16-bit | MPEG-4 ALS |
|---|---|---|
| Compression | uncompressed | lossless |
| Sample behavior | Full quality kept | Full quality kept |
| Typical use | AU is Sun's simple container, usually holding 8 kHz telephony audio. | MPEG-4 ALS compresses PCM losslessly with random access. |
When not to convert AU to MPEG-4 ALS
- Skip MPEG-4 ALS for the smallest share: lossless output stays large, so prefer a lossy target when sending AU files.
- Keep a master copy: repeated exports stack small losses, so archive AU before batch MPEG-4 ALS shares.
Limits
Starting point: AU - AU is Sun's simple container, usually holding 8 kHz telephony audio. Headers are minimal; verify sample rate after conversion. Few players open it; convert FLAC for sharing. Encode MPEG-4 ALS (MPEG-4 ALS) from AU at 256k for music or 128k for speech, starting from the master.
How conversion works
Conversion runs entirely in your browser with FFmpeg WASM. Files never leave your device.
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FAQ
How do I convert AU to MPEG-4 ALS?
Drop your AU file onto this page, choose quality and codec settings, then click Convert. The result downloads as MPEG-4 ALS instantly. All processing runs in your browser.
What codec is used for MPEG-4 ALS?
The default codec for MPEG-4 ALS is MPEG-4 ALS. You can change audio parameters in Advanced mode.
How do you store my files?
We do not store any processed audio. All conversion happens entirely in your browser using FFmpeg WASM.