Digital music services like Apple Music and TIDAL provide music in ‘lossless’ formats. But what does lossless mean and do you need it? — Apple Music, TIDAL and Qobuz tout themselves as providing ‘lossless’ music (CD quality, 16-bit, 44.1kHz), as well as high-res (96kHz or 192kHz at 24bit) whilst Spotify dishes out music in ‘lossy’ formats, currently limited to 128–320kbps (similar to mp3’s). What is ‘lossless’ audio?