Some streaming services, such as Spotify, offer a lossless audio option to their subscribers—a feature that promises higher-fidelity sound at the cost of increased bandwidth and greater storage usage. But this service raises a question: Is it worth paying more and using more data for this type of audio, or is it, in most cases, unnecessary?
What does “lossless audio” mean?
The term “lossless” is not the same as “lossy.” Both lossless and lossy formats undergo processes that reduce file size. The difference lies in whether, when the compression is reversed, exactly all of the original bits are recovered.
Formats like FLAC compress a track, and when decompressed, the waveform is restored intact; in contrast, MP3 and other lossy formats irreversibly discard information to save space. Codec designers apply knowledge of psychoacoustics to discard what they consider least perceptible to the human ear. That’s why not all “lossy” music sounds the same; the type of material (acoustic, orchestral, live recordings) and the quality of the mix influence how noticeable the difference is.
The Physics of the Ear and Listening Conditions
The typical hearing range is from 20 Hz to 20 kHz, and this range narrows with age or after prolonged exposure to loud noises. In addition, our brain filters and processes sound, causing many details to be “overlooked” by automatic perception.
Add to that the listening environment and equipment. Listening on the subway, with low-end headphones, or via Bluetooth—where the connection itself often limits the data rate—drastically reduces the chances of distinguishing a lossless file from one with high compression.
In practice, most listeners can’t tell the difference between a 320 kbps MP3 and a lossless version when listening under everyday conditions. If you don’t have a system that can take advantage of those subtle differences, why make life harder for ourselves?
How to Verify It Yourself
There are standardized methods for determining whether you can detect the difference. NPR and ABX tests are the most commonly used. The NPR test provides three files for comparison—uncompressed, MP3 at 320 kbps, and MP3 at 128 kbps—while the ABX method shuffles the samples and tests your ability to identify A or B at random, yielding a statistically valid result.
Before performing any of these tests, it is best to use wired headphones and an analog connection whenever possible, eliminate ambient noise, and turn the volume up to a high level without distortion. If you are using speakers, find a room that is as quiet as possible.
Many who call themselves “audiophiles” can discern differences between studio systems or high-end monitors, but a blind test is the only way to move from subjective impressions to a reproducible measurement.
How to Decide
If you plan to preserve a music collection, work on audio editing, or perform multiple conversions, the lossless format is practically a must. However, if you’re only interested in listening to music on your phone, in the car, or with standard wireless headphones, the practical benefit is minimal.
The cost in terms of data and storage space can be significant. Lossless files take up several times more space than their well-compressed equivalents. Try it out on your own computer; if you can't tell the difference in an ABX test, you'll save time and storage space—and money, too.
If, on the other hand, you notice differences and can appreciate the nuances, then lossless audio makes sense for you and your equipment. At the end of the day, what matters isn't the technical label, but whether your ears and listening habits can take advantage of it; if not, it's better not to complicate things.
