What is ALAC?
The ALAC format option in iTunes is short for Apple Lossless Audio Codec (or simply Apple Lossless), and it does not compress your music to the extent that sound quality is impacted. The audio is still compressed like AAC, but the big difference is that the sound quality remains identical to the source. This lossless audio format is similar to other formats you may have heard about, such as Free Lossless Audio Codec (FLAC). The file extension used for ALAC is .m4a, which is the same as for the default AAC format. This can be confusing if you see a list of songs on your computer’s hard drive, all with the same .m4a file extensions. Therefore, you won’t visually know which ones have been encoded with ALAC or AAC unless you enable the Kind column option in iTunes. To enable the Kind column, select View Options > Show Columns > Kind.
Why Use the ALAC Format?
The primary reason for wanting to use the ALAC format is if audio quality is important to you, but here are a few more ALAC pros:
No Loss of Quality When Ripping CDs: If you want to preserve your original audio CDs, ripping them with the ALAC option will produce perfect copies of your discs. Safely Convert to Other Formats: You may know that converting from one lossy format to another lossy format degrades audio quality. However, if you use a lossless format like ALAC, then you can convert to anything without losing any audio information. Recover Damaged Original CDs: Storing your physical music collection (e.g., CDs) as ALAC files gives you the option to re-create them if the originals become damaged or lost. You can burn the ALAC files to a recordable CD, which will give you an identical copy of the disc you originally backed up.
Disadvantages of Using ALAC
Maybe you don’t need ALAC even if it’s superior to AAC in terms of audio quality. The downsides to using ALAC include:
Larger Files: Just like other lossless codecs, ALAC encoded audio produces files that are larger in size than lossy formats. You will, therefore, need more storage space than if using AAC. Unless audio quality is important, then this trade-off might not be worth it. Less Compatible With Hardware: Compared to popular lossy formats like AAC, there is less support for ALAC. If you only use Apple devices, this isn’t a problem since all Apple devices support ALAC. However, if you think you may use portables from a mix of manufacturers in the future, ALAC may not be your best solution—although, you can convert from ALAC to other widely supported formats, like FLAC. Will You Hear the Difference? If you intend to listen to music through basic earbuds, you won’t hear any difference between AAC and ALAC. Even though lossy formats like AAC discard audio data, a decent bitrate (256 Kbps and higher) is usually good enough for most people.