Playback Designs MPD6 or Bricasti M21?

@acurus, okay, I understand.  I own the Bricasti M21 DAC very much.  It substantially improved the sound quality in my system and I strongly recommend it.  Their customer support is great and I encourage you to call them to get more info on the M21 DAC AND your questions answered.  

Couple notes as a dealer of both brands - the M21 "Network Card" can be used as a streamer the same way as the PBD Stream X module can.  StreamX is a $3K option on the MPD-6.  Both can leverage MConnect and JPlay to work as a streamer or serve as Roon or UPnP endpoints.  The person above asking if they needed something else if they have a Roon Nucleus on network, no.  This will serve as a Roon endpoint and nothing else would be required.  

The MPS-X with a separate server is superior to the StreamX module but StreamX is a very good place to start.  

Both units are very well manufactured.  Bricasti is built like a tank, no question but when you pick up a PBD DAC it is obvious how well it is made.  Both made in the US, just on opposite coasts.

The major difference is going to be in the image and a few features.  The MPD-6 and M21 tonally are quite similar but the image is different.  The MPD-6 is a smidge more detailed with a large soundstage that is tall and wide and has excellent depth and good stability.  The Bricasti delta sigma DAC probably has a larger image in terms of height and width but I don't believe it is as detailed and I don't think has the absolute depth of the PBD.  The R2R is nice and a different flavor altogether.  

Both are upgradable.  The firmware on both can be refreshed introducing new features.  The modular nature of the Bricasti also makes longer term hardware upgrades possible.  Both have amazing customer service and relatively few issues.  

Bricasti's Amps and Preamps are absolutely superb and obviously, the M21 will match aesthetically.  The M21 has a bunch of filters to fine-tune the sound. And obviously it has R2R, 1Bit DSD and the Delta Sigma DAC meaning you have more options.  Playback has no filters.  You like it as is or you do not.  Fortunately, Andreas knows what most people like and the MPD-6 is very appealing to many.   

I have the M21 and very happy with it. Mike at Audio Archon sells both but recommended the M1 which i originally purchased. I decided to go ahead and upgrade to the M21 to benefit from the analog volume control. I was glad I did. The M21 is worth the extra coin. I use a PS Audio Airlens as a ROON endpoint to process the streaming. The M21 has better power supplies than the MPD-6 at least from what i can observe looking at open chassis images.

Yesterday, I received -- and installed -- my build-to-order M21 as well as Bricasti's M19 SACD transport. These two components replaced a Wadi 8 CD transport (which I may, or may not, sell), a Theta Digital Compli SACD player, a Wadia 2000 DAC, and a Lumin T2 streamer/DAC. Like others, I seriously considered Playback Design's MPS-6, too.

Compared to what I had previously listened to in my home, the M21's [even] initial performance was utterly astounding; all aspects are simply better -- clarity, realsim, detail, soundstage depth, etc. are amazing. I have yet to compare the various DAC offerings and filters; these were the default settings. What I did not expect was the improvement the M19 provided to shiny discs. I have to say that the M19/M21 combination -- with the I2S connection between them -- gave real credence to the belief of many that CDs can still deliver a better performance than is obtainable from 44.1K via the Internet.

I have never spent so much money before on a source (or two sources together). Frankly, I was worried ahead of time that I would not be able to discern much difference from what I already owned. Was I ever wrong! To put this in perspective, one of my local high-end audio stores has on display a Berkely Audio Design, Luxman, Shunyata, and Magico system costing $221,000. This is my "reference standard"; up until now, my own system wasn't even close. But no longer -- if anything, with the addition of the two Bricastis, I believe that my updated system surpasses what I was able to hear in that store.