If you have an extensive digital music collection or are looking to create one, you might be confused, and perhaps overwhelmed, by all the different audio file formats out there. This article will explain what each is, how they work, and which one might suit you and your music best. Generally, each audio file format is meant for a different purpose and hence performs in different ways.
First Things First: What is an Audio Codec?
A general familiarity with audio codecs is necessary to understand how audio file formats themselves work. A codec is simply a program that compresses and decompresses data for transmission and reception, respectively. When it comes to audio, in particular, the codecs will affect your listening experience regardless of the device that you are listening on. In terms of codec, audio can be lossy or lossless; or it can be compressed or uncompressed. In short:
Lossy audio uses a compression technique that does not decompress audio files back to their original form after they are received. The degree of the digital compression itself is quite high, so the resulting files are quite small, and this can also affect the quality of the sound in certain cases. Thus, lossy audio formats should not be used in professional settings or when high-quality sound is needed. Examples of lossy audio are MP3 and AAC.
Lossless audio uses a compression technique that does, in fact, decompress audio files back to their original form after a transfer. Lossless audio still comprises of high degrees of digital compression, but it achieves this without a loss in size or a reduction in sound quality. Thus, lossless audio is better suited to situations where lossy audio ought to be avoided. Examples of lossless audio formats include FLAC and ALAC.
Uncompressed audio, lastly, uses no compression at all, so the sound in these audio files remains exactly the same as when it was recorded. Examples of uncompressed audio formats are PCM and WAV.
Cutting to the Chase: Audio Formats
We now look at the most common audio file formats available in the market right now.
MP3 is the common name for a file format consisting of MPEG audio layer 3. The key reason for the popularity of MP3 audio, and MP3 players, as a result, is that it features a compression style that simultaneously saves space and maintains the original quality of the sound. MP3 audio is not the best quality sound out there, but it is the most versatile, which is why it is used in most mobile devices. MP3 is, however, compatible with a wide range of devices, and is often used for audio file-sharing; thanks to its manageable size. MP3 also works well on websites.
MP4 can often be mistaken for an improved version of MP3 audio, but this is certainly not the case; the only similarities come from their namesake, not functionality. MP4 can also sometimes be used to refer to video files rather than audio files, because it is, in fact, an audio and a video file. MP4 audio uses a comprehensive type of media extension which is capable of different kinds of media. MP4 audio is supported by most devices nowadays that support MP3 as well. However, MP4 requires different codecs in order to be read.
M4A is a file format that uses MPEG audio layer 4, which means that M4A is, more or less, the improved version of MP3 that MP4 is often mistaken for. M4A also uses audio compression in a more modern setting, because it aims to meet the increased demand for higher quality which has become prevalent thanks to cloud storage and larger hard drives in contemporary computers. For instance, Apple’s iTunes uses M4A for music downloads rather than MP3, due to M4A’s smaller size and superior quality. However, M4A is thus also limited when it comes to compatibility.
FLAC stands for Free Lossless Audio Codec. FLAC audio files are compressed into a smaller sized version of the original file. FLAC is a rather sophisticated and relatively less-used type of audio format; its advantages can sometimes be overshadowed by the fact that it can require special downloads to be able to function. This is inconvenient for sharing files. Regardless, FLAC is unique in that its lossless compression saves size and allows file sharing in a way that allows you to return the file to its quality standard, so FLAC can save you a lot of space and a lot of time spent on uploads and downloads.
AAC stands for Advanced Audio Coding and it is a lossy codec. AAC files are small in size; they have discarded bits so they cannot provide a near-replica of the original sound. AAC files are generally best used for online streaming, and they sound perfectly fine to most users. While some argue that AAC offers better quality than MP3, it has not been able to defeat MP3 in terms of popularity. Regardless, AAC is commonly used both in mobile devices and on different platforms such as YouTube and PlayStation.
WAV audio, or Waveform Audio Files, store waveform data, as the name indicates. This data represents an image which then demonstrates the strength and volume of the sound in different parts of the file. Think of this concept like an ocean wave; the water is at its loudest and strongest when the wave is at its highest, which is how waveform in WAV works as well. When its visuals are high, the sound in the file increases, and vice versa. While WAV audio often uses sound compression, this is not always the case. WAV files are usually uncompressed, although, again, this is not required. WAV files are typically used on Windows systems.