New Members Guide

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This page is meant to address concerns and questions which regularly come up on the forums by members new to the Hydrogenaudio community. In the past these questions lead to ever repeating discussions of the same fashion, straining moderators and regular users alike.

Should I rip my CDs to FLAC or WAV?[edit]

Short answer[edit]

Advantages of FLAC
  • Reduction of file size
  • Allows tagging of files
  • Better error detection
Advantages of WAV
  • Plays in virtually any audio player

Basically FLAC is the best choice in all cases, since nowadays there are audio players which play FLAC on every major platform. So unless you commonly use software which is not able to play or decode FLAC files, there is no compelling reason not to use it.

Long Answer[edit]

First of all, FLAC is, as the name implies, a lossless audio compression format. This means that the decoded FLAC file will not only sound exactly the same as the WAV, but it will be identical bit-by-bit to the WAV file. You can think of FLAC (or any lossless compression algorithm) like the ZIP algorithm to compress data. You will get the exact data out as you put in, just like ZIP, just the file size will be smaller.

The reduction in file size directly implies that the bitrate of the resulting FLAC file is smaller than that of the input WAV file. This fact often is confusing to people new to audio compression, because they were trained to accept that bitrate equals audio quality. So how can FLAC have the exact same audio quality as WAV, but have a smaller bit rate? This confusion is due to a misconception of the meaning of the word "bitrate", while in fact it is very simple. Bitrate simply is a measure of the number of bits allocated per second of audio. Since FLAC reduces the file size due to compression, this of course means that it needs to allocate less bits per second of audio than the source WAV file. In fact, for a lossless compressor it is preferable to achieve the lowest possible bitrate, because this directly means that the file was reduced to the smallest possible size while still being completely identical to the input file.

The reduction in file size is already the biggest advantage of FLAC over WAV, but for most users another point is likely of equal importance. Most everyone knows and is used to metadata stored in audio formats, a popular example being ID3 tags in MP3 files. These allow to attach information about the audio stream directly to the file without the need for external files, or a specialized folder structure for the audio files. This immensely helps with keeping an ever-growing music collection organized, because the information about the audio data is always kept together with the audio stream itself, even when moving the files around on the hard drive. FLAC has a defined way of storing this kind of information too, which is structured similar to ID3 tags and can be edited by a multitude of tools for many platforms. Storing of metadata is not well-defined for WAV, and in fact most audio players and tagging tools are unable to read metadata from WAV files. This means that a user who stores music using WAV files has to meticulously keep his folder structure intact, or store the metadata in special file along with the audio files. Moving the files to another folder or losing the external metadata file means that the information is completely lost.

These are strong points in favour of FLAC, but there also have to be mentioned a point which slightly speaks against it. Since WAV is such a simple and old audio format, virtually every audio software is able to read the format. This is not the case for FLAC, in fact the standard media players on both Windows (Windows Media Player) and Mac OS (iTunes) do not support FLAC. The user has to check beforehand if the software he intends to use is able to work with FLAC. While there are audio players for every major platform which can play FLAC, some users might for one reason or another not want to use them, or have to use a very specific piece of software (e.g. a specific Audio Workstation without FLAC support). In that case keeping WAV files might be preferable, though due to their lossless nature, FLAC files can be decoded to WAV to be used in the relevant piece of software.