AAC (Advanced Audio Coding)

AAC is a lossy audio codec that delivers better sound quality than MP3 at the same bitrate. It is the default audio format for Apple Music, YouTube, and most streaming services. AAC supports multichannel audio and is part of the MPEG-4 standard.

MIME Type

audio/aac

Type

Binary

Compression

Lossy

Advantages

+ Better audio quality than MP3 at equivalent bitrates
+ Native support in Apple, Android, YouTube, and streaming platforms
+ Supports multichannel surround sound (up to 48 channels)
+ HE-AAC profiles enable high-quality low-bitrate streaming

Disadvantages

− Lossy compression still discards audio data permanently
− Licensing fees apply for AAC encoder distribution
− Some open-source tools have limited AAC encoding support

When to Use .AAC

Use AAC for streaming audio, podcasts, and mobile delivery where better quality than MP3 at lower bitrates is desired.

Technical Details

AAC uses a modified DCT with improved psychoacoustic models, temporal noise shaping (TNS), and prediction tools. Profiles include AAC-LC (Low Complexity), HE-AAC (high efficiency for streaming), and xHE-AAC.

History

AAC was developed in the mid-1990s by a consortium including Dolby, Fraunhofer, Sony, Nokia, and AT&T. It was standardized as ISO/IEC 13818-7 (MPEG-2 Part 7) in 1997 and improved in MPEG-4 (ISO/IEC 14496-3).

Convert from .AAC

.aac → .ac3 .aac → .aiff .aac → .alac .aac → .amr .aac → .ape .aac → .avi .aac → .flac .aac → .flv .aac → .m4a .aac → .mid .aac → .midi .aac → .mkv .aac → .mov .aac → .mp3 .aac → .mp4 .aac → .ogg .aac → .opus .aac → .wav .aac → .webm .aac → .wma

Convert to .AAC

.ac3 → .aac .aiff → .aac .alac → .aac .amr → .aac .ape → .aac .avi → .aac .flac → .aac .flv → .aac .m4a → .aac .mid → .aac .midi → .aac .mkv → .aac .mov → .aac .mp3 → .aac .mp4 → .aac .ogg → .aac .opus → .aac .wav → .aac .webm → .aac .wma → .aac

Related Formats

.ac3 .aiff .alac .amr .ape .flac .m4a .mid .midi .mp3 .ogg .opus .wav .wma

Related Terms

AAC Audio Codec M4A

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