What Is Lossless Audio, and Do You Really Need It?

There’s a difference, of course, between “putting some music on” and “listening to music.” The first is just a nice way of disturbing the silence while you get on with some task or other, while the second is a way of transporting you into a world of emotion and expression. And so it follows that while the first doesn’t require an exceptional level of quality to be effective, the second benefits no end from sounding as close to the artist’s original intentions as is possible. For digital music, that’s lossless audio.

You may have heard more about lossless audio recently, thanks to a growing number of music streaming services offering it as part of their subscriptions, most recently Spotify. But what exactly is lossless audio, how do you get it, and does it really make a difference? Let’s get into it.

What Is Lossless Audio?

At the risk of stating the obvious, lossless audio is digital audio that has lost none of the information originally contained in the recording. This doesn’t mean it hasn’t been compressed—both lossless and “lossy” files will have been through a process of compression in order to make sure the digital file is of manageable size to be streamed reliably. It’s the size of the file after that compression that defines whether it’s lossless or not—and there are two numbers that are relevant here.

First is the “sample rate,” which is the number of times per second the analog audio signal is examined as it’s being converted into digital information. The higher the sample rate, the more accurate the digital information should be—a compact disc has a sample rate of 44.1 kHz, for example, which means the analog signal is sampled 44,100 times per second as it’s being converted to digital.

Next, there’s “bit depth,” which signifies how much of the analog sound wave each sample of the signal is capturing. The higher the number here, the more of the analog audio signal is being examined, and the more accurate the transcription of the information from analog to digital. It also helps deliver greater dynamic range, which is the distance between the quietest and the loudest moments in a recording. Compact disc uses 16-bit audio.

The 16-bit/44.1 kHz resolution that compact disc uses was acknowledged at the time of the technology’s development as the best compromise between capturing as much data as is audible to the human ear as possible and keeping digital audio files down to a manageable size. And it has endured—any digital audio file with a resolution of at least 16-bit/44.1 kHz can be described as lossless, as long as it’s stored in a lossless format like FLAC (Free Lossless Audio Codec) or, indeed, on a compact disc. Anything less than this—often expressed differently, in kbps—can safely be termed “lossy,” while anything larger takes us into the realms of “high-resolution” audio (which is ultimately anything higher than CD quality, but generally it’s considered as anything with a 24-bit bit depth or above).

Is Lossless Audio Better Than Regular Audio?

Short answer: yes. Information is knowledge, after all, and knowledge is power—or, in this instance, knowledge is access to as much audio information as possible, which keeps your music sounding as the artist intended.

The slightly longer answer: yes, as long as you’re using equipment capable of revealing all of the information contained in a lossless audio file, then it will sound better* than the lossy equivalent. This means everything from your source of music, how well the digital information is converted to analog, its amplification and, finally, the speakers or headphones that serve it to your ears.