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AU to Opus - Online Audio Converter
Convert AU to Opus online. Private, client-side - no uploadrequired. Batch conversion, quality presets, codec control.
Convert AU to Opus
Drop AU audio here or click to select
AU
Opus (Opus)
About AU to Opus
Convert AU to Opus. AU is Sun's simple container, usually holding 8 kHz telephony audio. Opus adapts from 6 kbps speech to 510 kbps music with low latency. CD-era hardware may not decode it; use MP3 for legacy players..
Why convert AU to Opus?
- Smaller files with Opus lossy compression.
- Keep quality where supported.
- Private, no upload - runs in your browser.
AU vs Opus
| Codec | PCM 16-bit | Opus |
|---|---|---|
| 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. | Opus adapts from 6 kbps speech to 510 kbps music with low latency. |
When not to convert AU to Opus
- Skip Opus 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 Opus 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. CD-era hardware may not decode it; use MP3 for legacy players. Encode Opus (Opus) 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 Opus?
Drop your AU file onto this page, choose quality and codec settings, then click Convert. The result downloads as Opus instantly. All processing runs in your browser.
What codec is used for Opus?
The default codec for Opus is Opus. 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.