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[LazyBorzoi]

Can someone explain to me what bitstreaming option do exactly?
The MC recommended choice is None.
Do I understand this correctly that in that case all decoding is done by MC?

I have an external DAC that understands DSD natively. Would it make sense to change bitstreaming to DSD in MC if I want to play DSD through my DAC?
If I do so (choose Bitstreaming->DSD), what happens to PCM encoded files (flac)? Where are they decoded in this case?

Thanks in advance!

[RoderickGI]

I got lazy and answered inside your quote.

Can someone explain to me what bitstreaming option do exactly? Maybe
The MC recommended choice is None. Correct. JRiver recommends that you let MC do the decoding, generally, unless there is good reason to Bitstream. MC does pretty good decoding.
Do I understand this correctly that in that case all decoding is done by MC? Yes

I have an external DAC that understands DSD natively. Would it make sense to change bitstreaming to DSD in MC if I want to play DSD through my DAC? Probably. That is a reasonable reason to Bitsream. A better reason is when playing video with ATMOS, which MC can't decode. But if you prefer your DAC's decoding, then yes, go ahead and do that.
If I do so (choose Bitstreaming->DSD), what happens to PCM encoded files (flac)? Where are they decoded in this case? PCM would then be decoded by MC. Only DSD files would be Bitsreamed.

[LazyBorzoi]

Thank you, RoderickGI.
Just one last question: is there a reason not to bitstream DSD to my DAC which is a delta-sigma dac? I'm just curious what happens if I let MC decode DSD... I assume it will send PCM to it then?

[Awesome Donkey]

If you don't enable and use DSD bitstreaming, MC will convert DSD to PCM on-the-fly (which is a lossy conversion - DSD to PCM or vice versa always is).

[LazyBorzoi]

If you don't enable and use DSD bitstreaming, MC will convert DSD to PCM on-the-fly (which is a lossy conversion - DSD to PCM or vice versa always is).

Thank you, sir!
Looks like I've been playing my DSD correctly all along (using bitstreaming) 

P.S. It's good that this setting (Bitstreaming - > DSD) doesn't do anything to the regular PCM (flac) files. It would have been bad if I had to switch this setting every time I chose to play DSD after flac or flac after DSD...

[RD James]

If you don't enable and use DSD bitstreaming, MC will convert DSD to PCM on-the-fly (which is a lossy conversion - DSD to PCM or vice versa always is).

Though it could be argued that this is a technically accurate statement, the phrasing is loaded and quite misleading.
DSD is arguably not a lossless format to begin with, as 1-bit audio encoding is a destructive process. It adds distortion and a lot of noise.

Though converting from 1x DSD to say a 24-bit 96kHz PCM track is not a reversible process, you are not losing anything by doing so - only filtering out noise that was added by the 1-bit encoding, and what is being filtered out is beyond the human range of hearing.
You arguably don't even need a sample rate that high when converting DSD to PCM, and 24-bit 48kHz would be more than enough.
 

Just one last question: is there a reason not to bitstream DSD to my DAC which is a delta-sigma dac? I'm just curious what happens if I let MC decode DSD... I assume it will send PCM to it then?

Bit-streaming bypasses all DSP inside of Media Center.
You cannot use Media Center's volume control, features like volume leveling, room correction, speaker calibration, or any other DSP you may wish to apply to playback.
It also means that you are reliant on the DAC's filter to cut out all the junk high frequency noise present in the DSD signal. Some DACs do a bad job of this, while Media Center does a good job of it.
Many DACs suffer from pops/clicks or gaps in playback when switching to/from DSD mode, rather than remaining in PCM mode.

[LazyBorzoi]

Though it could be argued that this is a technically accurate statement, the phrasing is loaded and quite misleading.
DSD is arguably not a lossless format to begin with, as 1-bit audio encoding is a destructive process. It adds distortion and a lot of noise.

Though converting from 1x DSD to say a 24-bit 96kHz PCM track is not a reversible process, you are not losing anything by doing so - only filtering out noise that was added by the 1-bit encoding, and what is being filtered out is beyond the human range of hearing.
You arguably don't even need a sample rate that high when converting DSD to PCM, and 24-bit 48kHz would be more than enough.
 Bit-streaming bypasses all DSP inside of Media Center.
You cannot use Media Center's volume control, features like volume leveling, room correction, speaker calibration, or any other DSP you may wish to apply to playback.
It also means that you are reliant on the DAC's filter to cut out all the junk high frequency noise present in the DSD signal. Some DACs do a bad job of this, while Media Center does a good job of it.
Many DACs suffer from pops/clicks or gaps in playback when switching to/from DSD mode, rather than remaining in PCM mode.

James, thank you so much!
Yeah, I just came across a paper by Lipshitz and Vanderkooy (https://sjeng.org/ftp/SACD.pdf) that explains a quite bit (pun intended :-)) about why and how DSD creates all that noise and distortions! Given that their paper came out in 2001, I wonder if DAC manufacturers addressed the issues raised by the authors since then?


On your comment about "converting from 1x DSD to say a 24-bit 96kHz PCM"... Can it really filter out all the noise and distortions introduced by DSD format?

[RD James]

James, thank you so much!
Yeah, I just came across a paper by Lipshitz and Vanderkooy (https://sjeng.org/ftp/SACD.pdf) that explains a quite bit (pun intended :-)) about why and how DSD creates all that noise and distortions! Given that their paper came out in 2001, I wonder if DAC manufacturers addressed the issues raised by the authors since then?


On your comment about "converting from 1x DSD to say a 24-bit 96kHz PCM"... Can it really filter out all the noise and distortions introduced by DSD format?

To eliminate distortion, you need 2 bits of TPDF dither applied to the signal - and the signal itself needs at least a bit. So you need at least 3 bits for distortion-free audio.
What they have done with DSD is increase its sample rate. This pushes the distortion to lower levels and the noise to higher frequencies, but the format is still inherently compromised by being 1-bit.
 
You can't filter out distortion after the fact, but you can filter out the excessive high frequency noise that was added - and Media Center does it well. Just make sure that Media Center's dither is set to TPDF.
Your DAC should also be filtering out these high frequencies if you bit-stream DSD, but most DACs are a "black box" and you have no idea what it's doing or if it's doing it well.

[LazyBorzoi]

To eliminate distortion, you need 2 bits of TPDF dither applied to the signal - and the signal itself needs at least a bit. So you need at least 3 bits for distortion-free audio.
What they have done with DSD is increase its sample rate. This pushes the distortion to lower levels and the noise to higher frequencies, but the format is still inherently compromised by being 1-bit.
 
You can't filter out distortion after the fact, but you can filter out the excessive high frequency noise that was added - and Media Center does it well. Just make sure that Media Center's dither is set to TPDF.
Your DAC should also be filtering out these high frequencies if you bit-stream DSD, but most DACs are a "black box" and you have no idea what it's doing or if it's doing it well.

That makes sense. Thanks!

[LazyBorzoi]

Just make sure that Media Center's dither is set to TPDF.

I can't find where this setting is in the MC. Can you point me to the right place?

[~OHM~]

I can't find where this setting is in the MC. Can you point me to the right place?

It's under Audio>Advanced

TIP: when searching Tools>Options......there is a search bar at the bottom....use a few keywords!

[LazyBorzoi]

It's under Audio>Advanced

TIP: when searching Tools>Options......there is a search bar at the bottom....use a few keywords!

Thanks!

[robspierre]

Since there appears to be some wizards and alchemists in residence on this topic, (and I can't find my topic anywhere else), I seek enlightenment...

My DSP Studio works in every other application fine; the EQ, headphones and the like. But when I stream stuff from the internet, it appears the DSP is bypassed entirely.  The Audio Path ( feature under Player pulldown menu) appears to confirm this, as nothing is shown there when I'm Streaming.  I have tried roughly 2 billion possibilities or 4 hours of fiddling around, with no luck. How come like that? Miracles kindly accepted and welcome!

[RoderickGI]

Read this: https://wiki.jriver.com/index.php/WDM_Driver

Most likely, when you stream from the internet now, you are playing audio to the Windows Default Audio Device, and not through MC at all. Easy to check by looking at the Windows Volume Mixer. You can use the WDM Driver to change that.

[dctom]

when I use bitstreaming for DSD and MC finishes the track, and starts playing a PCM file, I get a strange ringing distortion on the newly started PCM file. I have to stop the track then restart it - it then plays it no problem.
Anyone else noticed this peculiarity, the DAC automatically recognises DSD or PCM.

[RoderickGI]

the DAC automatically recognises DSD or PCM.

It is probably still a DAC issue. Apparently, some DACs have issues switching between formats. It would be worth researching that for your DAC brand and model. But if you list what you have, someone may have more information.

[kr4]

I am posting this here since the original post (which did not mention DSD or bitstreaming in its title) seemed to garner little interest and help:

I run the output of MC to a miniDSP U-DIO8 and its 3 AES3 outputs to a trio of Mytek Brooklyn DACs using the miniDSP ASIO.  I can play multichannel FLAC/PCM in 5.1 but when I try to play DSD output over DoP only the first 4 channels play DSD64 while channels 5-6 play 24/197.4 noise.  Any  ideas?

(The output hardware/software is capable of this as I can play DSD64 in 5.1 via Roon without any external manipulation.)

[RoderickGI]

First thought: As you are using DSD over DoP, set the volume to 100% in MC and control volume externally. As you are using DoP, and volume adjustment will corrupt the DSD, I think. I'm no expert in this. Maybe that is only an issue when Bitreaming DSD over DoP.

Question: When playing DSD64 in 5.1 via Roon, are you using DSD over DoP for a fair comparison? Are you Bitstreaming? Are you sure Roon isn't decoding to PCM?

[kr4]

First thought: As you are using DSD over DoP, set the volume to 100% in MC and control volume externally. As you are using DoP, and volume adjustment will corrupt the DSD, I think. I'm no expert in this. Maybe that is only an issue when Bitreaming DSD over DoP.

Yes, volume is set at 100% but, in any case, why would that have an effect on 2 channels and not on the other 4?

Question: When playing DSD64 in 5.1 via Roon, are you using DSD over DoP for a fair comparison? Are you Bitstreaming? Are you sure Roon isn't decoding to PCM?

Yes, I often compare performance via JRiver vs. via Roon when I am testing audio equipment.  However, the Myteks display "DSD64" for all channels with Roon while, with MC, the Myteks display "DSD64" only for the first 4 channels (Myteks #1 and #2).  The 3rd Mytek displays "24/176.4 PCM" for the LS/RS channels and outputs a mild hash noise.

[RoderickGI]

The 3rd Mytek displays "24/176.4 PCM" for the LS/RS channels and outputs a mild hash noise.

Well, that explains the noise. The third Mytek isn't recognising the DSD over DoP, so it is just trying to play the PCM. MC is no doubt outputting DSD over DoP for all channels.

I can't say why two work and the third doesn't though. Maybe try swapping a couple of Myteks and see if the failed channels move? Yes, I understand it works in Roon.

You are Bitstreaming aren't you, so there is no DSP on the 5th and 6th channels in MC?
How does MC display the three Myteks in the Zone? As a 6 channel device? How does Windows display the audio output?

[kr4]

Well, that explains the noise. The third Mytek isn't recognising the DSD over DoP, so it is just trying to play the PCM. MC is no doubt outputting DSD over DoP for all channels.

MC confirms this.

I can't say why two work and the third doesn't though. Maybe try swapping a couple of Myteks and see if the failed channels move?

I tried that and the problem moves with the output cable and not with the particular Mytek.

You are Bitstreaming aren't you, so there is no DSP on the 5th and 6th channels in MC?

None.

How does MC display the three Myteks in the Zone? As a 6 channel device?

MC sees it as the miniDSP Streamer interface which can support up to 8 channels and I have the output set to 5.1.

How does Windows display the audio output?

Dunno.  Why is that relevant if using the miniDSP ASIO driver?

[Matt]

I tried that and the problem moves with the output cable and not with the particular Mytek.

Since it moves with the cable, could that be evidence that one of the cables is bad?

I'm puzzled by your post because Media Center should be pretty bullet proof outputting multi-channel DSD.

[kr4]

Since it moves with the cable, could that be evidence that one of the cables is bad?

No because the same cable/configurations work with Roon. As a result, I believe that there is something that is not set up right in MC.

I'm puzzled by your post because Media Center should be pretty bullet proof outputting multi-channel DSD.

Me, too.  I will spend more time with it this weekend and see whether something is different for those channels that is, somehow, corrupting the DoP.

[dtc]

First thought: As you are using DSD over DoP, set the volume to 100% in MC and control volume externally. As you are using DoP, and volume adjustment will corrupt the DSD, I think. I'm no expert in this. Maybe that is only an issue when Bitreaming DSD over DoP.

Question: When playing DSD64 in 5.1 via Roon, are you using DSD over DoP for a fair comparison? Are you Bitstreaming? Are you sure Roon isn't decoding to PCM?

Typically, ASIO drivers ignore the MC volume controls when bitstreaming DSD. But some drivers try to adjust the volume as if it is a normal PCM stream, causing the DSD to play as noise. Seems like this is a flaw in the ASIO drivers.   If MC had an option to disable volume control for ASIO bitstreaming of DSD (native or DoP) like there is for WASAPI, this would be a mute point.  Currently, it is a rare problem, but it is not one most users even think about.

[dtc]

Kal - have you tried DoP over WASAPI - that is if WASAPI supports multi channel. Just a thought.

[kr4]

Kal - have you tried DoP over WASAPI - that is if WASAPI supports multi channel. Just a thought.

I do not know if that is possible with this device.  Worth a try.  Thanks.

[kr4]

Typically, ASIO drivers ignore the MC volume controls when bitstreaming DSD. But some drivers try to adjust the volume as if it is a normal PCM stream, causing the DSD to play as noise. Seems like this is a flaw in the ASIO drivers.   If MC had an option to disable volume control for ASIO bitstreaming of DSD (native or DoP) like there is for WASAPI, this would be a mute point.  Currently, it is a rare problem, but it is not one most users even think about.

Neither WASAPI nor Direct work for multichannel DSD-DoP.  There are no settings/changes in MC as indicated by the blue asterisk (and confirmed by the pop-up window.  There are no volume changes in the ASIO driver; all locked and linked.

[RoderickGI]

So whatever is happening, is happening outside MC, and is being done to channels 5 & 6, regardless of which DACs are connected to those channels.

So it sounds like either the ASIO driver or the miniDSP U-DIO8, both of which are outside MC, is applying some volume adjustment to the audio for channels 5 & 6, thereby corrupting the DSD stream. Or maybe there is a problem with the supplied miniDSP U-DIO8 cable.

You have said the miniDSP U-DIO8 volume settings are locked and linked. Linking only links each stereo pair, not all channels. Are you sure channels 5 & 6 are set to full volume?
If there is a mix up in the cable, maybe the output you want is on the cable for channels 7 & 8? Try connecting the DAC for channels 5 & 6 to the brown cable for 7 & 8.
If that doesn't work, tell MC to output the top two channels to channels 7 & 8, and connect your third DAC to the brown cable. Do those two channels work now?
Has it worked before? Can you downgrade the miniDSP U-DIO8 firmware/driver to see if an earlier version works?

You get the idea. Test each component in the audio path outside MC, and see if you can locate the issue.

[dtc]

RoderickGI  - All good suggestions, but remember Kal says it works with Roon.

[RoderickGI]

Ah. Forgot that bit. That does imply the problem is in MC. I would still try though, as it could be a hardware/driver detection issue.

If it works using channels 7 & 8, then maybe MC is detecting channels 5 & 6 on the miniDSP U-DIO8 incorrectly.
For that matter, as channels 1 to 4 work, I would try outputting channels 5 & 6 on 1 & 2, 3 & 4, just to see if those combinations work.

If channels 5 & 6 always plays noise regardless of where they are output, then the source, MC, does look like the issue.

EDIT: Thinking about that, maybe it isn't possible to redirect channels when Bitstreaming DSD. Hmm.

[kr4]

So whatever is happening, is happening outside MC, and is being done to channels 5 & 6, regardless of which DACs are connected to those channels.

Not necessarily since the same hardware does 5.1DSD with Roon.

You have said the miniDSP U-DIO8 volume settings are locked and linked. Linking only links each stereo pair, not all channels. Are you sure channels 5 & 6 are set to full volume?

Yes.  All 8 channels (I use only 6) are at 0dB.

If there is a mix up in the cable, maybe the output you want is on the cable for channels 7 & 8? Try connecting the DAC for channels 5 & 6 to the brown cable for 7 & 8.
If that doesn't work, tell MC to output the top two channels to channels 7 & 8, and connect your third DAC to the brown cable. Do those two channels work now?

I have swapped the output cables and, with my current setup, whatever is connected to outputs 1,2  and 3,4 works fine, whatever is connected to 5,6 plays hash noise, and whatever is connected to 7,8 is silent.

Has it worked before? Can you downgrade the miniDSP U-DIO8 firmware/driver to see if an earlier version works?

I never tried multichannel DSD-DoP with this setup before.  I have sent inquiries about this to miniDSP and, so far, their reply echos what is here.

[kr4]

If channels 5 & 6 always plays noise regardless of where they are output, then the source, MC, does look like the issue.

Yes and the DAC playing the noise displays/synchs to a 24/176.2 clock.

[JimH]

That another player works isn't conclusive proof of where the problem lies. Bugs are triggered by a specific set of circumstances.

[kr4]

That another player works isn't conclusive proof of where the problem lies. Bugs are triggered by a specific set of circumstances.

Not conclusive but suggestive of the most obvious path for investigation.

[RoderickGI]

Hmmm, hard to progress from here.

The DACs are the Brooklyn DAC+ version, are they?

I would be trying to eliminate the miniDSP U-DIO8 and its ASIO driver, and then output Bitstreamed DSD64 DoP via USB to a Brooklyn DAC+, for just channels 5 & 6 or if three USB ports are available, all channels. I don't know if that is even possible in any available ASIO driver, but if so, that could narrow the field of investigation.

I assume that you have tried lots of different DSD64 sources and all exhibit the same problem. Because that would be the other obvious thing to look at; bad encoding of the DSD source, which the other player handles, but MC does not.

Another approach may be to reach out to other MC users with the miniDSP U-DIO8 who might be playing DSD64 DoP. I think there have been a few on the forum.
Maybe this is relevant: https://yabb.jriver.com/interact/index.php/topic,118432.msg819300.html#msg819300

[JimH]

Anything is possible.

[kr4]

The DACs are the Brooklyn DAC+ version, are they?

No. The original Brooklyns.

I would be trying to eliminate the miniDSP U-DIO8 and its ASIO driver, and then output Bitstreamed DSD64 DoP via USB to a Brooklyn DAC+, for just channels 5 & 6 or if three USB ports are available, all channels. I don't know if that is even possible in any available ASIO driver, but if so, that could narrow the field of investigation.

I will attempt that next weekend.

I assume that you have tried lots of different DSD64 sources and all exhibit the same problem. Because that would be the other obvious thing to look at; bad encoding of the DSD source, which the other player handles, but MC does not.

Not lots but nearly a dozen randomly chosen.

Another approach may be to reach out to other MC users with the miniDSP U-DIO8 who might be playing DSD64 DoP. I think there have been a few on the forum.
Maybe this is relevant: https://yabb.jriver.com/interact/index.php/topic,118432.msg819300.html#msg819300
[/quote]

[Matt]

If you take channels 0 and 1 that are outputting correctly and move them with Parametric Equalizer to 5 and 6 (which aren't working), what happens?

We need to figure out if it's the actual audio that's corrupt, or something in the mixer / driver on the output side.

[kr4]

Maybe this is relevant: https://yabb.jriver.com/interact/index.php/topic,118432.msg819300.html#msg819300

Yes, I know about that but the U-DIO8 has the outputs synched.

[kr4]

If you take channels 0 and 1 that are outputting correctly and move them with Parametric Equalizer to 5 and 6 (which aren't working), what happens?

We need to figure out if it's the actual audio that's corrupt, or something in the mixer / driver on the output side.

I doubt that the files are corrupt because I have played them with the same equipment via Roon as well as with several other DACs with MC.  IAC, I will try what you suggest next weekend.

[kr4]

I have resolved this issue with the help of Jim Hillegass and miniDSP's Tony Rouget. 

It turns out that, despite the multitude of options and variables, the critical factor is the number of channels on the recording.   If there are 6 channels, all's well in PCM and in DSD-DoP.  If there are only 5 channels, i.e., there is no LFE signal on channel 3 of a 6 (5.1) channel.  With PCM and specifying "5.1 channels" in output, MC successfully remaps the channels by inserting a silent channel 3.    With DSD Bitstreaming, of course, DSP Studio operations are bypassed and the output from a 5 channel file, regardless of output settings, results in the SL going to the subwoofer, SR going to the SL and the SR speaker being silent.  Asking MC to convert DSD to PCM fixes the channel layout.

Unfortunately, the vast majority of Classical multichannel SACD releases are in 5.0, not 5.1.  For all of these, PCM conversion (or a native DSD-capable DAC) is necessary.

Considering my ancient experience with such 5.0 dscs in the past, it is a bit embarrassing that I did not recognize this sooner.  Duh.

[dtc]

So since Roon works, it must be shifting and filling the channels appropriately.

I have never really understood why "bitstreaming" was necessary. As long as all DSPs are off and there is nothing else changing the output (like dithering), then a bit perfect output of the PCM format with DoP encoding should be fine.  Straight MC output is bit perfect, whether it is 2 channel or 6 channel.  So DoP should work without bitstreaming, unless bitstreaming is doing something else to force bit perfect output.  If so, the remapping needed to make 5 channel work should be possible, unless I am missing something.

EDIT:  I have a 2x DSD file (2 channel only) that is stored in DoP format. That is, it is a flac file with the DoP format for  the 2x DSD in it.  It plays fine with DSPs turned off. That confirms to me that bitstreaming is not needed when using DoP.  That means it should be possible to have MC create a DoP file for a 5 channel DSD with the appropriate channel mapping, much like it does with a normal PCM file. It would require changes to MC, but it should be possible.

[RoderickGI]

So since Roon works, it must be shifting and filling the channels appropriately.

Well, I would consider channel mapping to be DSP, so if Roon works, it is applying DSP even when it says it is Bitstreaming. I'm not surprised actually.

That means it should be possible to have MC create a DoP file for a 5 channel DSD with the appropriate channel mapping, much like it does with a normal PCM file. It would require changes to MC, but it should be possible.

It sounds like for 5.0 channel DSD files, all that is necessary is to have a Zone set without Bitstreaming, and just do the channel mapping in DSP, with an output format of DSD in DoP. No changes required in MC, other than settings.

KR4, is that what you were able to do with these files?

Thanks for sharing the solution by the way. Next time, I shall try to confirm what is actually in the file early in the discussion! 

[dtc]

Well, I would consider channel mapping to be DSP, so if Roon works, it is applying DSP even when it says it is Bitstreaming. I'm not surprised actually.

It sounds like for 5.0 channel DSD files, all that is necessary is to have a Zone set without Bitstreaming, and just do the channel mapping in DSP, with an output format of DSD in DoP. No changes required in MC, other than settings.

KR4, is that what you were able to do with these files?

Thanks for sharing the solution by the way. Next time, I shall try to confirm what is actually in the file early in the discussion! 

Don't think you can activate DoP without bitstreaming.  It would be a solution if the ASIO interface had a Convert to DoP without bitstreaming.  But, per Hendrik's comment in the other thread, creating a silent channel in DSD is not straightforward and would have to be added to the DSP.

[RoderickGI]

Don't think you can activate DoP without bitstreaming.

Well, I certainly can on my stereo system, which has no Bitstreaming settings. But I am using WASAPI and not ASIO, which may force a difference. I don't have a multi-channel DSD setup.

But, per Hendrik's comment in the other thread, creating a silent channel in DSD is not straightforward and would have to be added to the DSP.

Yep, that would be an issue, even with the channels moved around. If you were playing a 5.0 track in a 5.1 container, then the .1 channel would likely be noise.

[dtc]

Well, I certainly can on my stereo system, which has no Bitstreaming settings. But I am using WASAPI and not ASIO, which may force a difference. I don't have a multi-channel DSD setup.

Yep, that would be an issue, even with the channels moved around. If you were playing a 5.0 track in a 5.1 container, then the .1 channel would likely be noise.

The only ASIO option to get DoP also says bitstreaming, although I guess I have not tried to do any DSP in that situation. But I think it ignores DSP Studio.

With WASAPI, if I do not have bitstreaming on for DSD in Audio setup, then it converts to PCM. I need bitsreaming on for DSD to convert to DoP.  In the case of WASAPI, I think bitstreaming  turns on DoP.

Try playing a DSD track with bitstreaming on and with it off.  Look at Audio Path and see what it says.  For me, on says DoP in Audio Path and off either errors or gives me the PCM conversion rate (not the DoP rate).

[Hendrik]

But, per Hendrik's comment in the other thread, creating a silent channel in DSD is not straightforward and would have to be added to the DSP.

To be clear, its not a real problem technically to do it, but quite simply that DSD has no true "zero" (DSDs 1-bit format is actually -1/+1, to indicate the changes in the signal). So as a workaround, typically a inaudible ultra-high-frequency noise signal is being used - the one we have in MC is the most commonly used "0x69" signal, which translates to very low energy 352.9kHz noise line (AFAIK). This seems to be mostly an industry standard, so its probably fine, and DSD DACs should filter it out entirely.

Unfortunately all that channel handling is all in the PCM DSP code, but maybe Matt could be convinced to add a special case somewhere for 5.0 -> 5.1 DSD Bitstreaming.

PS:
As a final note, as mentioned in the other thread, "Bitstreaming" for DSD is not anything magic. It has no special meaning. We refer to outputting anything thats not PCM as "Bitstreaming", and DoP falls into that category. There is no special output mode involved in Bitstreaming DSD over PCM (in contrast to native DSD over ASIO), the only difference is that MC is told to not decode DSD to PCM - if it detects DSD in the first place, if you already packed it as DoP into a PCM container, then you are by-passing all of that anyway.

"Bitstreaming" in general does not pass the source file 1:1 to the output without any changes. There will always be changes that make it possible to transport the data over a PCM link in the first place. If you have a typical DSD file, this will include packing it in a DoP container - which means its not quite the same data that it used to be, but this "wrapping" is only on the outside, and the actual audio data on the inside remains untouched. DSD is in a special place as such that you basically bitstream every channel individually, so you can re-arrange the channel, for example, and still pass the audio data untouched to the source - only in a different order. Equally, you could drop channel, or add a new one, since DSD is not "compressed" but only a different raw representation, it adds more freedom.

(Since this seems to be brought up repeatedly - if you encode a DSD file as DoP and throw it into a PCM container like FLAC, then it is effectively just PCM to Media Center, it does not know that its DSD, it'll treat it as plain old PCM, so you need to turn off all DSP. As such, you also really cannot compare this behavior to playing native DSD files)

[dtc]

Thanks Hendrik. That is very helpful.

The DoP in flac example was just to show that there is no magic in "bitstreaming" of DoP, as you have confirmed. It was not meant to be a direct comparison to the MC process.

Thanks.

[kr4]

Unfortunately all that channel handling is all in the PCM DSP code, but maybe Matt could be convinced to add a special case somewhere for 5.0 -> 5.1 DSD Bitstreaming.

I would appreciate that but I am not advocating for it because, although the majority of Classical multichannel DSD recordings are in 5.0, playback of multichannel DSD is easily accomplished in the vast majority of cases as native DSD to dedicated multichannel DACs.  AFAIK, the issues I raised apply only to using the miniDSP U-DIO8 and, if they exist, comparable devices. 

It would be a solution if the ASIO interface had a Convert to DoP without bitstreaming. 

Yup.

[RoderickGI]

Thanks a lot for the explanation Hendrik. Much appreciated.