FLAC is the preferred container because it is lossless but compressed (approximately 40-60% of the original WAV size). Unlike MP3 or AAC, which surgically remove frequencies to save space, FLAC preserves every single bit of data. When you search for a FLAC rip of GNX , you are looking for a bit-for-bit identical copy of the master delivered to digital retailers (Qobuz, Tidal, HDTracks).