Both Mp3 and AAC are setups for audio files. Mp3 (MPEG-1 Audio Layer III /MPEG-2 Audio Layer III) and AAC (Advanced Audio Coding) are coding formats used for digital audio.
AAC was designed to be the successor of mp3 with more improvements and higher efficiency, but the sound quality of both audio files is almost the same.
Key Takeaways
- MP3 and AAC are both audio compression formats used to reduce the file size of audio files.
- MP3 is more widely used and compatible with more devices, while AAC provides better sound quality at lower bitrates.
- MP3 is a lossy format, which means it loses some audio data during compression, while AAC is a more efficient lossy format that preserves more audio data.
MP3 vs AAC
MP3 and AAC are digital audio file formats used to encode and compress audio data. MP3 is an older format with good sound quality and small file size. AAC is a newer format with greater sound quality and a slightly bigger file size.
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Mp3 is a standard technology that uses a format to compress a sound into the around one-twelfth size of an original file while preserving the original level of sound quality.
AAC can code audio files from minimum to high bit rates. AAC is built as a successor to Mp3 with more effective and efficient sound quality.
Also, AAC has up to 48 channels, whereas MPEG-1 mode has 2 channels and MPEG-2 has around 5.1 channels only.
Comparison Table
Parameters of Comparison | MP3 | AAC |
---|---|---|
File extension | It uses .mp3 as an extension. | It uses .m4p, .m4a, .m4b, .mp4, .acc as an extension. |
Quality | Mp3 offers a lower voice quality than AAC and the same bitrate | AAC offers a better voice quality although it gives a very loose compression |
Popularity | Mp3 is available on all devices | AAC is popular among iPod and iPhone but not as popular as mp3 |
Release | 1994 | 1997 |
Frequency | 16 kHz – 48 kHz | 8 kHz – 96 kHz |
What is Mp3?
Mp3 (MPEG-1 Audio Layer III) is digital audio developed by the Fraunhofer Society (Germany) using some help from scientists in the US.
Mp3 encodes data using a lossy data compression (regarding audio compressions).
Mp3 is famous because of its ability to compress files and make it convenient to store music.
4 parts describe the Mp3 algorithm
- Breaks the audio system into smaller pieces (called frames)
- Passes the sample into a 1024-point FFT (Fast Fourier transform)
- It then Counts and encodes each sample (known as noise allocation)
- Formats the bitstreams.
The encoder algorithm and bitrate are also terms on which the quality of sound encoded by mp3 depends. The quality of sound mostly depends on the encoding parameters.
The mp3 coding technology is patent-free, as all the patents expired in 2012.
Mp3 supports only up to 2 channels in MPEG-1 mode and up to 5.1 channels in MPEG-2 mode. Mp3 handles a frequency of 16 kHz to 48 kHz.
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What is AAC?
Advanced audio coding is a successor for mp3 with more efficient audio quality and has a higher frequency sound of 8 kHz to 96 kHz.
AAC achieves a higher sound quality than mp3 at the same bit rate.
AAC composes of 48 full-bandwidth channels of 96 kHz. AAC Is also a standard audio format for iPhones, iPods, etc.
The major improvements that AAC has over mp3 are as follows.
- It has more sample rate.
- More channels of high bandwidth (48)
- Higher coding efficiency
- More flexible, i.e., various methods can be used for various frequency ranges.
- Additional tools.
AAC has firm industry support and hence is a strong contender.
AAC is an international standard many companies have used, for example, Dolby Company Inc, Sony Corp., and Nokia Corp.
Although still, not all devices use AAC. Mostly all iTunes and iPods have given access to AAC audio format.
Main Differences Between Mp3 and AAC
- The main difference between AAC and Mp3 is the frequency that the two use. While AAC uses a frequency of 8 kHz to 96 kHz, Mp3 uses only 16 kHz to 48 kHz.
- The number of channels in AAC is 48, wherein Mp3 mode MPEG-1 has only 2 channels and MPEG-2 mode has around 5.1 channels.
- The length of the block of both audio formats also varies a lot. AAC uses a block size of 1024 (or 960 samples), and Mp3 uses a block size equivalent to 560.
- Mp3 has a file extension of .mp3 whereas AAC has extensions like .m4a, .m4b, .m4p, .m4v, .m4r, .mp4, .aac.
- Both audio files use a different MIME type (Multipurpose Internet Mail Extensions). AAC uses audio/aac, audio/aacp, audio/3gpp, audio/3gpp2, audio/mp4, etc. Mp3, on the other hand, uses audio/MPEG as its MIME-type
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