In the last few years, digital audio has become a bit more complex than it used to be. You can listen to digital files in a wide variety of formats and we’ve written blog posts about these and the differences between compressed, lossless and high resolution files before. There is one format that’s supported by some of our products that’s different to any other digital media though. This format is called DSD and there are some myths and misconceptions about the format that we’re going to try and clear up.
DSD stands for Direct Stream Digital. It’s a high-resolution format that produces a high-resolution signal in a different way to that employed by the PCM system that can be transmitted as WAV, FLAC, ALAC or AIFF. If we were to look at a ’24 bit 96kHz’ file- a commonly used high resolution sample rate, this contains a stream of information 24 bits in size. This stream of information is then sampled 96,000 times a second- giving us the 96kHz part- to produce a signal that is then converted to an analogue signal by a DAC. The system has been used since the dawn of CD (which uses a 16/44.1kHz signal) and it also represents the basis of how our ATF upsampling process works.
DSD takes a different approach to the creation of a high resolution audio signal. Instead of using many bits of information in the signal, DSD uses a single bit. However, instead of sampling the information several thousand times a second, this single bit samples 2.8 million times a second to generate the audio signal. The result is still a high-res signal it’s just generated in a completely different way.