Over the course of the past five years of high speed audio DAC development, we’ve received two common questions. First, how to incorporate DSD256 playback on Mac platform? Second, how to make native DSD playback setup easier? With the current DoP (DSD over PCM) standard, the main frustration primarily occurs with the inability to playback DSD256 on the Mac platform, which accounts for at least 50% of the current music servers in use. The most common alternative, however, is utilizing native DSD on the Windows platform which comes with its own software setup issues as well as the need to install the required software driver From a technical perspective, DoP does well at being compatible with USB, SPDIF, AES and other potential digital inputs at the expense of ADDING 50% of overhead to the protocol in USB interface. Quick note here, with every music sample that’s transmitted from computer to DAC, you need to dedicate 8 bits in front as a DSD marker. On top of that, you all also need to drop the last 8 bits inside that 32 bit package due to SPDIF/AES being only 24-bit. For more information on DoP open standard, please refer to the link and the chart below.dsd-guide.com/dop-open-standard
Digging in deeper raises the question, “Why do we need a marker of every DSD music samples”? The answer is rather simple. Unlike the USB interface, SPDIF/AES interfaces are only SINGLE direction from source to DAC. There is no feedback endpoint or other mechanism that lets the DAC communicate with that computer that it’s DSD compatible. The benefit of adding this marker is relatively one sided. From the DAC’s point of view there is no benefit. Every music sample it receives from the computer (which could be 384,000 or 768,000 times per second) the DAC needs to detect if the first 8 bits are of a certain pattern, if yes, it grabs the middle 16 bits out of 32 bits which in the end wastes half of the bandwidth and adds 200% times of the computing power simply in order to make sure EACH music sample is DSD (or not). Exhausting right?
Enter, our solution: LH Labs Announces PureDSD Mode