The term "lossless" is a big one in music streaming right now, no doubt because Apple Music and Spotify have announced they're bringing lossless quality audio into the mainstream. Apple is bringing lossless tracks to Apple Music sometime this June, and Spotify launching a lossless tier of its streaming service, called Spotify Hifi, "later this year."
It's true that lossless quality music streaming has been around for years, thanks to dedicated lossless streaming services like Tidal, Deezer, Qobuz and, more recently, Amazon Music HD — but it's always been expensive (like twice as expensive as most "Premium" subscriptions). Now that Apple and Spotify are getting into the mix, lossless audio is about to get way more affordable and accessible.
But what is lossless music anyway? How much better is it than what you're currently listening to? Can you even tell the difference with your current ears and equipment? Here's a rundown of everything you need to know.
What does "lossless" mean?
Digitally downloaded or streaming music has traditional come in "compressed" forms, like the MP3 or more recently AAC, the format used by the iTunes Music Store. These are files that have pointedly squished so they take up less storage space on your smartphone or digital music player. This squishing process is "lossy"; the end result is missing detail that the previous, unsquished version had, specifically at the low and high ends, so that it doesn't sound nearly as good.
"Lossless" doesn't mean uncompressed, but rather it refers to a type of compressed digital audio file that uses advantaged data compression algorithms so that the audio track doesn't "lose" any detail in the compression process. For context, the average size of a compressed audio file, like a MP3 or a AAC, is about 1/4 the size of its original recording. The average size of lossless compressed audio file, such as FLAC or ALAC (Apple Lossless), is now a little more than 1/2 the size of its original recording.
Is there anything better than lossless?
Lossless just means that no detail has been destroyed in the compression process; the quality of the lossless file therefore depends on the original source that's being compressed. In popular use "lossless" means the same quality as a CD (16-bit/44.1 kHz), but there are a number of lossless streaming services that offer even higher-quality digital audio files. For example, Tidal gives its HiFi subscribers the option of listening to Master Quality Authenticated (MQA) certified tracks (up to 24bit/96kHz), while Amazon Music HD gives its subscribers the ability to listen to "Ultra HD" (up to 24-bit/192kHz).
The catch is that most lossless streaming services don't have a huge catalog of these ultra high-resolution audio tracks. And not every lossless streaming service supports them.
How does lossless audio compare to the music I'm already streaming?
The bitrate of a digital audio file, or the amount of data transferred per second, is the primary metric we use to determine audio quality. The lower the bitrate, the less information and the worse a digital audio file is going to sound.
If you've been a paying subscriber to a streaming service like Spotify or Apple Music for years, you've been listening to digital audio files with a max bitrate of 320 kbps and 256 kbps, respectively, which is about the same audio quality of an MP3. But that's only if you've flipped some switches in settings. Default bitrates are even lower. Spotify's default or "normal" setting delivers audio with a bitrate 96 kbps.
The bitrate of a normal lossless audio track is around 1,411 kbps. This is over four times the audio quality of an MP3 file (with a bitrate or 320 kbps). So if you're wondering whether your audio equipment (and ears) can do justice to higher bitrate tunes, a great way to find out is experiment with telling the difference between the various flavors of lossiness streaming services already give you.
Can lossless audio be streamed over Bluetooth?
The short answer is "no."
In order to listen to lossless digital audio files, you have two main options. You can use an analog connection, like connecting your wired headphones to your smartphone or computer. Or you can stream the lossless audio over a Wi-Fi, through a pair of active speakers, such as KEF Wireless II or even multi-room speaker like Sonos (thanks to Qobuz).
There are technologies that let you stream high bitrate audio over Bluetooth. For example, if your smartphone and headphones support either of some audio codecs, such as Sony's LDAC (up to 990kbps) or Qualcomm's aptX Adaptive (up to 570 kbps), you can stream stream high bitrate and low latency audio files over Bluetooth. However, these audio files aren't lossless (which is 1,411 kbps).
What is FLAC? Is that lossless?
There are several different lossless audio codecs, which are digital music file formats that support lossless and CD quality audio. FLAC (Free Lossless Audio Codec) and ALAC (Apple Lossless Audio Codec) are two of the most common. FLAC music files have been popular for years, but the downside is that they are not supported by Apple's devices and services. This means that if you have an iPhone or Mac and you subscribe to a lossless streaming service that plays FLAC digital audio files, you won't be able to play your music in its full lossless glory. (This is how Apple, with its new lossless audio codec, ALAC, is going to persuade music enthusiasts who own an iPhone to switch over to Apple Music.)
Is "lossless" the same thing as "hi-fi"?
Sorta. The term "hi-fi," which stands for high fidelity, doesn't have an exact definition any more. (It used to be synonymous with stereo back in the day.) Most audio professionals refer to hi-fi as audio that's the same quality as a CD or a vinyl record, which has a sample rate of 16-bit/44.1 kHz.
The term "lossless" refers to a digital audio file that has the sample rate as a CD (16-bit/44.1 kHz). For years, the highest resolution audio that many lossless streaming services like Tidal, Deezer and Qobuz offered was CD-quality. Now that higher resolutions are becoming available for streaming, the water is getting muddier again.
Should you subscribe to a lossless streaming service?
Only once you've verified that you can actually tell the difference.
The truth is that the vast majority of people can't really hear the difference between a regular MP3 file and a lossless FLAC or ALAC file. The other thing is that, if you want to hear the better audio quality that a lossless audio track can deliver, you need to have the proper components that support it, such as the right speakers, headphones and streaming device.
In order to get the most of our a lossless streaming service, you need to be streaming from a device that supports that specific streaming service's lossless tracks. For example, if you have an iPhone or Mac, there are only a few lossless streaming services that support ALAC (Apple's lossless codec), such as Tidal HiFi and Qobuz (and Apple Music soon).
Additionally, if you normally listen to music on your wireless headphones or earphones, such as AirPods or Bose Headphones 700, since it relays on a Bluetooth connection (which can't play true lossless audio) there's a good chance that you won't be able to experience the best of a lossless streaming service.