I've been curious for a long time about treading the up-sampling to DSD path. Thought I would give it a try, in my usual budget oriented fashion via the Topping D10. There's not much to it - powered from the USB bus, so no wall wart. It can also serve as a USB/SPDIF converter. Quite small, but solid feeling. Plugged it in, and the Mac Mini recognized it right away. It is said to reproduce PCM to 32/384 and up to DSD256, no drivers required for macOS. It played Spotify at 384 khz PCM, which seemed to be controlled from Audio Midi that detected the max setting. Seemed OK. Playing a redbook file at native sampling rate I was unsure of the audio quality - quite a different presentation than the Bifrost. But that's not really why I brought this in. I had downloaded several DSD files for testing. However, so far I cannot get them to play as DSD - it down samples to PCM 32/352. I also tested with up-sampling PCM to DSD - this too did not work. Settings changes in Audirvana Plus demonstrated it needs to do DoP in order to get this to work. So with the native DSD handling set to DSD over PCM standard 1.1 it shows the DAC is capable of DSD128. So currently I am up-sampling any of the library files to DSD128. It will now also play the native DSD128 files. And like I've read here at the Haven, the DSD up-sampling is a bit of a game changer. I've just shuttled thru the various filters, and A (5th order) seems to give me the balance of detail and bass that I like. I can't see myself not upsampling with this little DAC. Still need to fiddle a bit, but I'm mostly there. I'm thinking the issue of native DSD playback may be more to do with El Capitan than the DAC. Will continue to look into that. And on the 'net there's video of a fellow using Volumio2 on an RPI3 playing back DSD files. Didn't think the Pi would be a suitable choice for a bus powered DAC, but there you go. Fun and games.