If this has been asked before, please re-direct me.
The DirectStream DAC is limited to 2x DSD and Bridge II to 1x. Are there any technical reasons that higher data rates are not available? If this is possible are there any plans to implement 4x or even 8x?
Been wondering this myself. I have DSD 128 (2x DSD) files on my USB drive and they do not play in the front USB input on the DMP. I have Bridge 2 on my DS Dac. Would the USB thumb drive play the DSD 128 file on that? I also have DSD 256 files and they don’t play either. My Oppo UDP 205 is capable of playing them no problem. So why can’t the DMP and DSD play them?
The current DS software supports DSD64 and DSD128. The Bridge II supports DSD64. The DMP supports DSD64 and under some circumstances DSD128 (different versions of the software do DSD128 a little better or a little worse.)
The Bridge II will never support DSD128. I doubt, (but don’t know for sure) that the DMP will ever support DSD256.
The DS hardware could support DSD256, but that’s not trivial. The FPGA is essentially DSD256 inside, but getting DSD256 to the DS would take new USB code in the DS, new USB drivers for Windows, MAC and Linux or I2S. Many I2S sources can’t do DSD256, but that out of PS Audio’s hands.
PS Audio wants to support DSD256 where it’s possible, but I don’t have any idea when it might happen.
Thanks Ted, that’s just what I wanted to know. Also thanks for the great work on Snowmass.
Version 3 of the USB Audio Device Class specification (September 2016) finally includes explicit support for DSD as an encoding format. But who knows how long we’ll have to wait before major operating system vendors and USB chipset makers implement that.
Until that time we’re stuck with version 2, which doesn’t explicitly support DSD. We have to use DoP, packing 16 bits of DSD inside 24 bits of what the USB system thinks is PCM. To support DSD256 this way would require the equivalent of 705.6kHz 24-bit PCM sample rate support from the USB ecosystem. The limitation in most platforms/devices using UAC2 is 384kHz sample rate.
Hence Ted’s comment about needing custom USB device code and custom drivers to get past DSD128 for now. I2S is the alternate pathway to get native DSD256 into the DAC but where do you source that I2S signal from?
(Re the Bridge, some time ago I heard that the I2S lines from the Bridge to the FPGA have only been qualified for the equivalent of 192kHz PCM or DSD64 as DoP. They may not be physically capable of carrying a higher data rate than that.)
Sorry for my Ignorance but reading the homepage PS AUDIO claims supporting DSD256, thus I bought my first DSD256 album.
When trying listening the DirectStream DAC plays only 10-14 seconds, then jumps to next track and plays 10-14 seconds, then jumps to next track and so on…
That is meant to be a great album, must give it a listen. The irony is it was recorded in DSD128 on a $1,000 Tascam DA-3000 machine.
I looked on NativeDSD and found the following from their catalogue:
So the majority of DSD is recorded at DSD64, which has broadly the same dynamic range as 24/96 PCM, which seems to be the most popular rate for recording classical music in PCM. DSD 64 is the most frequent available DSD rate, unsurprising as it really does not present any hardware issues.
PCM seems no different in that it is often specified as 24/192 due to the DAC’s capability (As Ted explains in relation to DSD), but 24/96 seems to be the most popular recording rate, at least for classical.
What I would be interested to know is what is the point of DSD512 and DSD1024 as a playback rate when DSD is never recorded at more than DSD256. Where do the extra bits come from and what is the purpose of them?
Hi Steve, this link may help you 
however disregarded that it seems that BRIDGE II nor the PS Audio DAC supports 256 DSD 
Hi @juacif
Below is what each port can handle. I tested the I2S for DSD 256 and it works, though I hardly have any DSDs. Bridge II does DSD 64 over PCM, which sounds quite good and not an issue for me and many others. CD quality is predominantly what I listen to, and in terms of sound quality DS DAC exceeds my expectations, but there may be other components, tweaks contributing.
I2S, and USB — 44.1kHz to 352.8kHz 16bit, 24bit, DSD 64, DSD 128 (I2S DSD 256 with Sunlight update)
TOSLINK – 44.1kHz to 96kHz 16bit, 24bit
XLR (AES/EBU)S/PDIF (coax)– 44.1kHz to 192kHz 16bit, 24bit, DSD 64
I was originally playing dsf. (DSD files) native through my Auralic G2. Now I have it set to up convert to 256 DSD into my DirectStream w/Sunlight and the Edcor 4400 mods! The sound to my ears is the best I’ve heard! I’ve only had one glitch where the music stopped playing. I think it’s the processor trying to up convert the data and not being able to keep up. The Auralic is playing thru a Matrix Spdif FYI.
I regret that the NativeDSD explanation lost me in the first two lines: “While a re-modulation from a lower to higher bitrate contains no additional program content bandwidth, it does accomplish two benefits: a multiplier of the bit density resolution by the re-modulated bitrate ratio, and the enabling of the playback DAC’s employing a gentler reconstruction filter/algorithm in the D/A process.”
I’m not even asking what that lot means.
What gear are you using from source to the DS to get 256?
With my DirectStream DAC, I am upsampling all PCM and DSD to DSD256 using HQPlayer and Roon and it works great with no issues.
sonicTransporter i9 → ultraRendu → Matrix SPDIF 2 → DSD
@Serhan I’m happy that it works for you.
I have a Synology NAS — sending dsd256 — PS Audio Bridge II and PS Audio DS DAC — the hardware manages to play 14 sec and stops…
I tested and alternative path,
Instead of the NAS I stored the files into a USB stick — PS Audio DS memory player connected with I2Sto PS Audio DS DAC.
It should work with the latest firmware but it doesn’t !!! It works fine with DSD128 but not DSD256.
The Bridge II card supports DSD64 only so you probably aren’t using that card for input. What are you using for input on the DSD DAC?
I would send nothing more than DSD64 to Bridge II. That’s what it was made to handle.
The I2S can definitely handle DSD256. If it’s showing128, then something in the playback chain is doing it.
I wish it looken like that in my system 
Odd that it works for 14 seconds. That may be a limitation of the Memory player and not the DAC.
