AU to HE-AAC - Online Audio Converter
Convert AU to HE-AAC online. Private, client-side - no uploadrequired. Batch conversion, quality presets, codec control.
About AU to HE-AAC
Convert AU to HE-AAC. AU is Sun's simple container, usually holding 8 kHz telephony audio. HE-AAC adds spectral band replication for efficient low-bitrate streaming. Needs an HE-AAC decoder; plain AAC players may play only half the bandwidth..
Why convert AU to HE-AAC?
- Smaller files with HE-AAC lossy compression.
- Keep quality where supported.
- Private, no upload - runs in your browser.
AU vs HE-AAC
| Codec | PCM 16-bit | AAC (HE) |
|---|---|---|
| Compression | uncompressed | lossy |
| Sample behavior | Full quality kept | Quality set by bitrate |
| Typical use | AU is Sun's simple container, usually holding 8 kHz telephony audio. | HE-AAC adds spectral band replication for efficient low-bitrate streaming. |
When not to convert AU to HE-AAC
- Skip HE-AAC for archival masters: lossy compression discards detail, so keep the AU original.
- Keep a master copy: repeated exports stack small losses, so archive AU before batch HE-AAC 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. Needs an HE-AAC decoder; plain AAC players may play only half the bandwidth. Encode HE-AAC (AAC (HE)) 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.