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What Is M4A and How M4A Differs from MP3 and Other Audio Formats

What Is M4A - Definition

M4A is a file extension created by Apple for storing audio data. The .m4a file signifies the audio layer of (non-video) MPEG 4 movies and are encoded with advanced audio coding (AAC) that is a lossy compression. As a new codec supposed to be raised as the new standard for audio file compression, M4A is generally regarded as the successor to MP3 and produces better audio quality and smaller size than MP3 file.

Seven years ago, Apple came along and wiped the floor of all the mobile devices with the iPad, iPod as well as iPhone. Clearly, all these Apple's masterpieces, including its media players like iTunes and QuickTime, favor its own M4A and perform well as M4A player. Besides, other gadgets that open M4A files also include Windows Media Player, VLC, Roxio Popcorn, Toast and Creator. It's mentionable that some media players only read the format that is renamed to MP4.


M4A Pros and Cons Compared with MP3 AAC AC3 WMA

Besides M4A, there are literally dozens of other audio formats to choose, including the most popular MP3, AC3, Windows Media Audio, OGG, to name a few. How M4A stacks up against MP3, WMA, or other audio codecs? Read on and follow the audio compression battle.

M4A vs MP3: Both M4A (MPEG 4 audio) and MP3 (MPEG3 audio) are audio compression formats, managed by the Motion Pictures Experts Group (mpeg). The following will list the detailed M4A vs MP3 comparison in terms of size, quality and compatibility.

Quality: M4A format is known as the Apple lossless Encoder (ALE), which aims to overtake MP3 and set the new standard in audio compression. It is considered better as far as quality goes when comparing M4A to MP3. Generally, it's recommended to save music as 192 kbps M4A audio to get both great sound quality and small file size.

Size: The general consensus of the file size in M4A versus MP3 is that the former sounds better than the latter when encoded at the same bitrate. For example, a 4 minute song encoded at 128kbps AAC (M4A) would be about 3.8MB in size. To have the equivalent audio quality in MP3 format, you'd need the song encoded around 192kbps, which would make the file larger than 3.8MB.

Compatibility: As of now, M4A has not yet MP3's mainstream success as the former is somehow limited only to PC, iPod, and other Apple devices. While Pretty much every computer, music player, and cell phone in the world can play mp3 files.

M4A vs WMA vs MP3: Window's Media Audio is Microsoft's contribution to high quality, lossy audio compression. Like most other new formats, M4A and WMA outperform MP3 in terms of quality and compression, particularly at lower bitrates. Consequently, WMA is probably the format of choice for streaming at low bandwidths. So if you purchase a song from online music stores including Napster, Wal-mart, and Musicmatch, it will be in WMA format. However, M4A is less platform restrictive than WMA as the latter is notably unplayable in Apple's iPod.

M4A vs MP3 vs AAC
M4A vs MP3 vs AAC

Tips: if sound quality is paramount, neither M4A nor MP3 is the best while WAV takes the throne as it is not compressed. But WAV files are 10 times bigger than M4A or MP3 files. So when it comes to collect music, WAV is not favored as it would take too much space. >> AAC vs AC3; AAC vs MP3

General Audio compression

Audio Compression Format

Sample Rate

Bit rate



8-192 kHz

8-529 kbit/s(stereo)

Yes: Dual, Mid/Side, Intensity, Parametric


8, 11.025, 12, 16, 22.05, 24, 32, 44.1, 48 kHz

8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160, 192, 224, 256, 320 kbit/s

Yes: Dual, Mid/Side, Intensity


32, 44.1, 48 kHz

32–640 kbit/s



8, 11.025, 16, 22.05, 32, 44.1, 48 kHz

8–768 kbit/s



1–655350 Hz

8, 16, 20, 24, 32



1–384000 Hz

16, 20, 24, 32


Tips: It must be an issue for everyone who wants to play M4A files on Samsung, HTC, PSP, or other M4A unfriendly devices. Probably the issue exists in M4A playback mostly from the video/audio codec problems. But all such issue can be fixed provided you own a right video converter in hand. And a video converter like MacX Video Converter Pro is absolutely the must-have program that is able to convert MKV, MTS, MP4, AVI, WMV to M4A encoded AAC, MP3, AC3, and other audio formats for you to play back on Mac computer, Apple, Android, Windows Phones and Microsoft devices easily, up to 16X faster than before.

Dig Deeper and FAQ about M4A

Q: What is the difference between .MP4 and .M4A?

A: .MP4 versus .M4A: .m4a, in brief, can only contain MPEG 4 Audio and is a filename extension used to represent audio files. But .mp4 may or may not contain MPEG 4 Audio and can be used for MPEG 4 video files. The .m4a filename extension is used for MP4 containers with audio data in the lossy AAC or its own lossless ALAC formats. The m4a files in the standard for iTunes DRM-free, unprotected content while the .mp4 or .m4v files are used for the iTunes DRM copy protected content.

Q: Is there a difference between M4A audio files and AAC audio files or are they exactly the same thing but with a different file extension?

A: AAC is an audio encoding scheme,while M4A is only a file extension. An AAC encoded audio can have the AAC, MP4 and M4A extensions.

Q: Some of the music files in my iTunes library are M4A vs M4P. Why is that?

A: Digital Rights Management is included in these files to restrict users' ability to share the files. DRM was always sold on M4P files while M4A files have no restrictions and they are free of DRM. Apple M4P files were sold with a 128 bit rate, which is much lower than what is required by M4A files with a 256 kbps speed.

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