AAC vs AU
Ein detaillierter Vergleich von AAC Audio und Sun AU Audio — Dateigröße, Qualität, Kompatibilität und welches je nach Workflow zu wählen ist.
AAC Audio
Audio FilesAAC is a lossy audio codec that delivers better sound quality than MP3 at similar bitrates. It is the default audio format for Apple Music, YouTube, and most streaming services.
Über AAC-DateienSun AU Audio
Audio FilesAU is a simple audio format from Sun Microsystems, commonly used on Unix systems.
Über AU-DateienVorteilsvergleich
AAC Vorteile
- Better quality than MP3 at equal bitrate — the industry standard since 2000s.
- Universally supported on every smartphone, OS, and browser.
- Efficient on battery thanks to widespread hardware decoding.
- Scales from 8 kbps speech (HE-AACv2) to lossy-transparent 320 kbps.
- Five-channel + LFE surround support out of the box.
AU Vorteile
- Trivially simple format — 24-byte header, then samples.
- µ-law 8-bit variant fits hours of speech in kilobytes.
- Stable since 1988; every major audio library reads it.
- Streaming-friendly: size field is optional.
Einschränkungen
AAC Einschränkungen
- Patent-encumbered — encoders have licensing fees, which is why open alternatives (Opus, Vorbis) exist.
- Slightly more complex to encode than MP3.
- Raw .aac streams carry no seek index — tooling often prefers M4A/MP4 containers.
- Lossy — not suitable for archival or studio production.
AU Einschränkungen
- Aging — obsolete outside legacy and compatibility scenarios.
- No metadata beyond a single annotation string.
- No native multi-channel surround support.
- Limited to 8 codecs, none modern.
Technische Spezifikationen
| Spezifikation | AAC | AU |
|---|---|---|
| MIME type | audio/aac | — |
| Extensions | .aac, .m4a, .mp4 (container-dependent) | .au, .snd |
| Standard | ISO/IEC 14496-3 | — |
| Variants | AAC-LC, HE-AAC, HE-AACv2, AAC-LD, xHE-AAC | — |
| Sample rates | 8-96 kHz | — |
| MIME types | — | audio/basic, audio/au, audio/x-au |
| Header | — | 24 bytes (magic, offset, size, encoding, rate, channels, info) |
| Codecs | — | PCM 8/16/24/32-bit, µ-law, A-law, IEEE float |
| Byte order | — | Big-endian |
Typische Dateigrößen
AAC
- Speech podcast (64 kbps) 1 MB/min
- 3-min music track (128 kbps) 3 MB
- 3-min music track (256 kbps) 6 MB
- Broadcast-quality 5.1 (384 kbps) 9 MB for 3 min
AU
- 10-second clip (8-bit µ-law, 8 kHz) 80 KB
- 10-second clip (16-bit PCM, 44.1 kHz stereo) ~1.7 MB
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Häufig gestellte Fragen
AAC (Advanced Audio Coding) is a lossy audio format standardized by ISO as the successor to MP3. It delivers better sound quality than MP3 at equivalent bitrates and is the default audio format for Apple products, YouTube, and most streaming services.
AAC (Advanced Audio Coding) is a com perdas audio formato padrãoized by ISO como o successor to MP3. It delivers better sound quality than MP3 at equivalent bitrates e is the default audio formato para Apple products, YouTube, e most streaming services.
AAC files play in iTunes, Apple Music, VLC, Windows Media Player, and all modern web browsers. AAC is natively supported on iOS, Android, macOS, and Windows.
AAC arquivos reproduzir in iTunes, Apple Music, VLC, Windows Media Player, e all moderno web browsers. AAC is natively suportado no iOS, Android, macOS, e Windows.
AAC is technically superior, offering better quality at the same bitrate. Use AAC for Apple ecosystem and modern devices. Use MP3 only when you need compatibility with very old hardware like legacy car stereos or basic MP3 players.
AAC is technically superior, offering better quality at the same bitrate. usar AAC para Apple ecosystem e dispositivos modernoos. usar MP3 only when you need compatibilidade com very old hardware like legacy car stereos ou basic MP3 players.