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Different playback formats
WAV (or WAVE)
Short for Waveform audio format, is a Microsoft and IBM audio file format standard for storing audio on PCs. It is the main format used on Windows systems for raw audio
and is Mac compatible. Uncompressed WAV files are quite large in size, so the WAV format has declined in popularity being superseded mainly by MP3 and Apple’s AAC format used on iPods.
However, it is still a commonly used, relatively “pure”, i.e. lossless, file type, suitable for retaining archived files of high quality, or for use on a system where hi-fi quality is required and disk space is not restricted. This is the format used by CD ripping software for direct copies of CD albums although Audio CDs use Red Book not WAV as their sound format. The commonality is that both audio CDs and WAV files have the audio data encoded in Pulse code modulation (PCM). WAV is a data file format for computer use that can't be understood by CD players directly. To record WAV files to an Audio CD the file headers must be stripped and the remaining PCM data written directly to the disc as individual tracks with zero padding added to match the CD's sector size. This means it is difficult to include album art, (tagging) track and title information when using WAV in a hard disc storage situation. FLAC is much better for this.
FLAC
FLAC stands for Free Lossless Audio Codec, an audio format similar to MP3, but lossless, meaning that audio is compressed in FLAC without any loss in quality. This is similar to how Zip works, except with FLAC you will get much better compression because it is designed specifically for audio, and you can play back compressed FLAC files on any audio playback device that supports the codec.
FLAC stands out as the fastest and most widely supported lossless audio codec, and the only one that at once is non-proprietary, is unencumbered by patents, has an open-source reference implementation, has a well documented format and has other independent implementations. Flac files are about a third of the size of WAV files generally and are the most economical way to reduce storage size and retain quality for large audio collections. With huge storage sizes now becoming available, it is questionable whether reducing file size is worthwhile as the difference is discernable. However, tagging is much easier.
MP3 (Mpeg-1 audio layer 3) (AAC-Apple)
Encoding system used to create small file sizes and uses “lossy compression”. An MP3 file that is created using the mid-range bit-rate setting of 128 kbit/s will result in a file that is typically about 1/10th the size of the CD file created from the original audio source. An MP3 file can also be constructed at higher or lower bit-rates, with higher or lower resulting quality. Lossy compression when de-compressed will not be the same as the original but close enough for the difference not to be noticed too much on portable audio or low quality systems. Totally redundant for quality audio playback MP3 is still useful in a portable setting.
Lossy compression does suffer from generation fatigue - repeatedly compressing and decompressing the file will cause it to progresively lose qaulity vry bdly. AAC is the Apple lossy compression codec found on iTunes. Sony and Nintendo also use it. Designed to be a successor to Mp3 it is generally held to be as good or better than MP3 but is used with extensions for proprietary digital rights management (DRM) making it less universal and more of a money spinner for Apple and Sony – surprise.
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