If you prefer to buy and download your music instead of paying a monthly fee to stream it, you probably want to buy that music in the highest-quality format possible. For many audiophiles, that means DSD and DXD, two formats that represent the pinnacle of hi-res digital audio performance, and Qobuz has just announced that it has added both as downloadable options within its online store. This makes Qobuz one of the only companies that lets folks stream or download in the highest possible quality.
For now, the DSD and DXD catalogs are tiny when compared to Qobuz’s lossless CD quality and hi-res FLAC library size. The company says “more than 22,500 tracks are now available, mainly in DSD format,” as opposed to its FLAC collection, which numbers over 100 million.
Why do audiophiles care about DSD and DXD? It’s all about the way these formats convert analog music into digital. All digital music must be sampled from an analog source by taking “snapshots” of the analog signal multiple times per second. In the case of CD-quality digital music, those snapshots capture 16 bits of data, 44,100 times per second, which is why we refer to it as 16-bit/44.1kHz. So-called hi-res audio increases the snapshot size to 24 bits and captures it at anywhere from 48,000 times per second (24-bit/48kHz) up to 768,000 times (24-bit/768kHz). Typically, hi-res audio uses 24/96 or 24/192. Higher sample rates are much less common.
DSD takes a different approach, with 1-bit snapshots taken anywhere from 2.8 million times per second at its lowest resolution (DSD64), up to a staggering 45.1 million times (DSD1024). This “stream” of bits is where DSD gets its full name: Direct Stream Digital, and audio purists believe it’s an inherently superior way of digitizing audio.
However, DSD is very difficult to work with if you need to edit or remaster it. To do so, it needs to be converted into DXD, a format that can preserve most of its original quality, yet which can be manipulated by digital audio workstations. DXD can be thought of as a super-high-quality version of FLAC, and it’s playable on any device that can decode and play FLAC files.
Qobuz gives you the option to download DSD in one of four quality levels: DSD64, DSD128, DSD256, and DSD512, though not all DSD tracks are available in all levels. DXD files are provided as FLAC 24-bit, available at 352 or 384 kHz.
In the past, most folks experienced DSD by playing Super Audio CDs (SACDs) discs in a compatible player. The player’s internal software and digital-to-analog converter (DAC) took care of the whole process, sending out an analog signal that any amplifier could accept.
DSD downloads are a different story. To play them, you need software that can read DSD files (usually tagged with the extension .dsf or .dff) and ideally, a DAC or a portable music player like the Astell&Kern Activo, that can process the DSD stream natively. Not all DACs can do this. NativeDSD, another source for buying and downloading DSD and DXD, maintains a handy list of which DACs can handle DSD.
If your DAC can’t process DSD natively, these files can still be played, but they must be downconverted to pulse code modulation (PCM) format first.
If you’re thinking of getting into DSD downloads, keep in mind: these files contain far more information than even hi-res FLAC files, so be prepared to set aside a lot of free space on your hard drive.
