Is WAV Lossless the Best Quality?

Theoretically, yes, but most people can't tell the difference between a WAV file and a FLAC file. I have a 25000-sample stereo recording, and I can't detect the difference.

What is a .WAV File?

A .WAV file is an ideal representation of the original waveform, complete with no loss or artifacts, and every sample of the original PCM digital audio is fully intact. This means it can be edited and manipulated at any sample point without additional processing. Almost all professional recording is done as discrete PCM data with no compression, which is precisely what a .WAV file represents. While the files are very large, they work just like magnetic tape, giving an exact representation of the waveform at every instant in time.

Mild Lossless Compression

Some recording systems perform very mild lossless compression to halve the file size without losing audio quality, but this requires processing for editing. In such cases, blocks of audio are compressed, and when an edit is needed within a block, the block must be decompressed to PCM first. However, once an audio project is completed and is being edited using a lossless codec such as FLAC, the files can be reduced by about half again without any change in audio quality. Once the player decodes the codec, you get back the same PCM data, which is the whole point of 'lossless' compression.

Lossy Compression and Audio Quality

Lossy codecs can compress audio to fit into much smaller data sizes. For example, MP3, WMA, or AAC can all make 2-channel 1400 kbps CD audio music fit into less than 200 kbs, and it can still sound very good. This means 7 times as much music can be stored in the same space. I used to make 12-hour long compilation MP3 CDs before USB sticks became common. However, lossy compression does lose detail, and you will never get back the original waveform or detail.

Why Convert to a Higher Quality Codec?

When converting an audio file from one codec to another, especially from a lossy format to a lossless one, the best you can do is simply decompress the file to play it. If you try to decode and then re-encode with a different codec even at a higher bit rate, the odds are that at best, you won't make any audible difference, but more likely, you will be adding new artifacts with another compression pass. If you have the original PCM encoding, using FLAC will maintain the same audio quality with no loss. If you have a file already in MP3, it makes no sense to decode it back to PCM, .WAV, or then encode it to FLAC as you will now have a much bigger file with the lossless bitstream of any artifacts of the low-bit rate MP3 embedded into this huge file. Simply copying the encoded MP3 will give the best sound quality.

Processing Functions and Codec Errors

Some processing functions claim to be able to remove artifacts and bring back the original detail, but in reality, they are just trying to cover up codec errors. The only time I ever convert to a different codec is when my player can’t play one of them. For example, I used to convert .MVA to either .WAV or .MP3 so they would play on my old MP3 disc player, but I kept the original files. With my newer player, which can play compressed files from a USB stick, I now can play the original compression without having to mess it up again. At home, I prefer to use PCM CDA, WAV, or FLAC, which are all lossless. For traveling with a lot of music, I like AAC at 256 kbps to get very good sound in a lot less space.