Spotify and Apple Music are bringing lossless music into the mainstream, but they aren’t the first to offer audiophiles a high-quality streaming experience. So what exactly does “lossless” mean in the context of audio, and how can you perceive it?
Lossless audio preserves details
To save disk space and bandwidth, music files are often compressed. MP3 was one of the first compressed formats to be introduced, with AAC/MP4 being the predominant format used today.
When a file is compressed, it is effectively compressed to a smaller file size. To do this, some data must be deleted. When data is deleted, audio quality is affected. You can hear it most clearly in the treble and bass of a recording, for example, of a cymbal crashing.
Lossless audio is also compressed, but compressed in a way that retains audio detail. Lossless audio is always presented in a CD quality resolution of 16bit/44.1kHz or better and can go up to 24bit/192kHz.
The tradeoff here is disk space (or bandwidth, if you’re streaming). Formats such as FLAC or ALAC (Apple Lossless) are about half the size of the original uncompressed recording. In comparison, a lossy version can consume much less space (about 1/5 of the original uncompressed recording) without collapsing completely.
How can you enjoy lossless audio?
Tidal was one of the first streaming services to actually push lossless audio, but the feature has since been added to Apple Music at no extra cost. Spotify is also about to launch a separate tier for lossless sound called Spotify Hifi. Other services that provide lossless audio include Deezer and Kobuz.
Before upgrading your subscription plan, make sure you have the necessary hardware to enjoy lossless audio. For example, many wireless headphones and Bluetooth speakers use their own lossy compression to deliver sound from your device to your ears.
This includes Apple’s entire AirPods line (yes, even the AirPods Max) and most standard Bluetooth headphones that use lossy codecs like aptX.
The good news is that new lossless codecs are on the way, like aptX HD. Keep in mind that some “high-res” solutions like LDAC (included on many Sony wireless headphones) don’t have the bandwidth to transmit lossless audio at all.
Some devices require an external digital-to-analog converter (DAC) to play music at resolutions above CD quality. For example, the iPhone’s DAC can output up to 3.5mm stereo jack or CD quality lossless audio via USB.
You can also buy media players with built-in high-quality DACs, which are specifically designed for high-resolution lossless audio.
Can you tell the difference?
Most people can hear the difference between a low-bitrate Napster-era MP3 and a modern AAC stream from Spotify or Apple Music. The real debate is whether you can distinguish modern streams from their lossless counterparts.
It’s possible that the equipment you use to hear the sound (headphones, amplifiers, room acoustics) makes a big difference to the quality of the stream.
If source quality is everything, be sure to check out Review Geek’s guide to mobile audiophile setup.