AC3 vs AAC vs EAC3: Audio Codecs Compared
AAC is built for efficient stereo music; AC3 and EAC3 are Dolby's surround-sound codecs for TV and film. Here's what separates them and when each is used.
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Convert AAC files →Three codecs, two different jobs
These three come up together on TVs, streaming boxes, and video files, but they were built for different purposes. AAC is a general audio codec optimized for efficient stereo (and multichannel) music. AC3 (Dolby Digital) and EAC3 (Dolby Digital Plus, or E-AC-3) are Dolby's surround-sound codecs, designed for cinema, broadcast, and home theater.
| Property | AAC | AC3 (Dolby Digital) | EAC3 (Dolby Digital Plus) |
|---|---|---|---|
| Introduced | 1997 | 1991 | 2005 |
| Primary use | Music, streaming audio | DVD, broadcast, home theater | Streaming, modern home theater |
| Channels | Stereo & multichannel (up to 48) | Up to 5.1 | Up to 7.1 (and beyond) |
| Efficiency | High (best for stereo music) | Lower (older) | Higher than AC3 |
| Typical bitrate | 128–256 kbps stereo | 384–640 kbps (5.1) | Lower than AC3 for same quality |
| Where you meet it | Apple Music, YouTube, phones | DVDs, TV broadcast, ATSC | Netflix, Disney+, streaming, 4K |
AAC vs AC3
For stereo music, AAC is more efficient and generally sounds better at a given bitrate — it's the right tool for songs and podcasts. AC3 exists for surround sound: it packs 5.1 channels into a stream that DVD players, TVs, and AV receivers universally understand. You wouldn't use AC3 for a music library, and you wouldn't use plain stereo AAC for a home-theater surround mix.
AC3 vs EAC3
EAC3 (E-AC-3 / Dolby Digital Plus) is the successor to AC3. It's more efficient — delivering the same or better quality at lower bitrates — and supports more channels (7.1 and up). That efficiency is why streaming services like Netflix and Disney+ use EAC3 for surround audio, where bandwidth matters. AC3 remains common for broadcast TV and physical media because of its enormous installed base of compatible hardware.
So which is "best"?
There's no single winner — it depends on the job:
- Music, phones, general audio: AAC.
- Surround sound on DVDs, broadcast, older AV gear: AC3.
- Surround sound on streaming and modern home theater: EAC3.
Extracting the audio track
If you've pulled a stereo AAC track from a video and want it to play everywhere, convert it to MP3 with our AAC to MP3 converter. New to the format? Start with What is AAC? For the AAC profiles used in streaming, see AAC-LC vs HE-AAC.
Turn an extracted AAC track into a universal MP3 free — no account, no software, no limits.
Convert AAC files →Frequently Asked Questions
Is AAC better than AC3?
For stereo music, yes — AAC is more efficient and sounds better at a given bitrate. AC3 exists for 5.1 surround sound, a job AAC stereo isn't meant for.
What's the difference between AC3 and EAC3?
EAC3 (Dolby Digital Plus) is the newer, more efficient successor to AC3, with support for more channels and lower bitrates. Streaming services favor EAC3; broadcast and DVDs still use AC3.
Which has the best surround sound?
For modern streaming, EAC3. For universal hardware compatibility, AC3. AAC can carry multichannel audio too but is most associated with stereo music.
Can I convert AC3 or EAC3 to AAC?
Yes, with a general audio converter — though surround channels may be downmixed to stereo. For a universal stereo file, MP3 is the safest target.