1. Digital Audio Basics
Digital Audio is a technology for modulating audio signals for the purposes of processing, storage and distribution. It is the basis for the modus operandi and the possibilities of the DAS HD-Players. Although there are a number of such modulation technologies, the most common are PCM and DSD. Here we explain everything you need to know about them, incl. concepts like sampling rate, bit depth, aliasing, Nyquist-Shannon-theorem, dithering, oversampling, digital filters, sigma/delta, jitter, pre-ringing etc. …
2. Digital-Analog Converter Technology
The digital-to-analogue converter (DAC) converts digital (discreetly modulated) audio signals into analogue (continuous) audio signals. It is of decisive importance for the quality of the digital sound reproduction. In principle, there are a number of alternative technical concepts available. In commercial audio, however, there are but two concepts of relevance: Delta/Sigma-DACs and R-2R-Ladder-DACs. As a variety of the latter, so called NOS-DACs (non-oversampling DACs) have gained importance over the last decade. Read here, descriptions of the most important DAC concepts and technologies …
3. Sense and Non-sense of High Sampling Rates
The development of digital technology enables ever higher sampling rates. On the one hand, manufacturers of the consumer electronics want to use this development to sell ever more products. At the same time, there is a broad movement in the audiophile community that hails this development to ever higher sampling rates as a continuous improvement in sound quality. On the other hand, however, there are good reasons to question, whether this continuous ‘Higher, Further, More’ of pure numbers is really serving sound quality. The question for the useful sampling rate boils down to the question for the useful frequency spectrum available for audio reproduction and digital filters. These questions are explored here in the context of the human hearing …
4. PCM vs. DSD
For several years now, there is a heated debate raging in the audiophile community, about the presumed superiority of one digital modulation method over the other (PCM vs. PDM=DSD). As of 2015 there are even a number of DACs from very highly reputed manufacturers, that not only convert DSD natively into analogue, but convert all PCM first into DSD before it converting to analogue. The rationale given is a purported improvement in sound quality (e.g. Nagra HD DAC, PS Audio DirectStream DAC, Playback Designs MPD DAC). Of course, still most DACs today convert all DSD to PCM before converting to analogue – however not for reasons of sonic improvement but simple economy. The reasons why DSD might be superior to PCM and their plausibility are discussed in some detail here …
5. Digital Audio Playback in Comparison to Vinyl Playback
When comparing the technical parameters of vinyl playback to those of digital playback, then digital playback is vastly superior. When actually auditioning vinyl and digital playback, matters can come across quite differently. This is puzzling and since vinyl playback is a lot of fun, it is worthwhile to investigate this seeming paradox in some detail …
6. HD-Players Compared to Streaming-Devices
Music streaming services receive a lot of media attention recently. The digital revolution has shaken the music industry to its very foundations – particularly its distribution model. Streaming services are an important element in the music labels’ efforts to recover control over their product distribution – just as much as download portals are. Streaming or downloading is a variant of the age-old alternatives of renting or owning. Both alternatives have their specific advantages and disadvantages for the music lover and are largely complementary …
7. Glossary
Like all other technological areas, Digital Audio has its own terminology. If you want to look up one of those technical terms, you may find it here …
