DSD options don't quite make sense in my sense: "DSD over PCM" (DoP) should even be available with a network player that doesn't support DSD because it may have a digital output that can be connected to a DAC that in turn may recognise the associated DoP markers.
In my particular case, a Roon-ready Bluesound Node is connected to a MacBook running the Roon Server via Ethernet and pipes the audio stream to a T+A HA 200 via co-axial RCA, which for PCM works perfectly. However, I cannot configure Roon to use DoP for the Node simply because this option doesn't show up in the audio settings. What is the problem here? Is it that the Node is not running in "Exclusive Mode" because it is not directly connected to the MacBook? Or is it that it itself cannot natively play DSD, which is totally irrelevant when using DoP as this is exactly the use case of DoP: A DSD stream mimicking a PCM stream as to be transparent to non-DoP-capable devices on the way? If the latter: Would it work with the new Bluesound Node Icon, which is natively DSD-capable, although I would not use that capability? Would it only work via USB? (The Node Icon seems to feature a USB audio output.) Thanks!
Describe your network setup
Irrelevant, because it only concerns DoP. The only point of interest may be that the Node is not "directly connected" but speaks to the Roon Server via Ethernet.
DSD isnt supported on older models of Blusounds. All DSD is converted to PCM via BluOS or in this case Roon. Even the latest ones dont currenlty support it but its touted for a future update now they all support USB out as standard, where it was added to the old nodes pretty late on in its development. Even when it does due to their internal DSP its more than likely all convereted to PCM before it hits the DAC. Why do you think the Node can play DSD as it cant, its can input it on the older machines but will always be converted to PCM, you cant get DoP.
“DSD over PCM” is a technical term, a specification how to make DSD look like PCM in a downstream until a device recognises the corresponding markers. I have a DAC which does and only use the Bluesound Node as a means to let the DAC work with Roon as a Roon-ready streamer. If I would get Roon to produce DoP, the Node would just pipe it to the DAC via the RCA output because it doesn’t even notice that it isn’t really PCM. The DAC then notices the 0x05/0xFA markers that DoP utilizes and interprets the remainder of the data as DSD - there is no conversion from DSD to PCM involved at any time.
I know what DoP is but the streamer has to support DoP for Roon to send DoP to it and in your case it doesn’t even if going on to an external DAC.
Bluesounds have all their outputs active at same time and they do not communicate back as which output is being used to Roon. Roon Ready is for the internal DAC which Roon has full visibility on, externals don’t. If you want DSD playback you chose the wrong device for the job. As I said Bluesound do not support DSD via DoP or Native. Have you tried via the BluOs app I assure you it won’t work either they have to be converted to PCM.
Well, exactly: I consider it akin to a bug to not allow DoP even if the streamer declares to not be DSD-capable. DoP is even designed so as to not blast your loudspeakers or whatever if a DAC mistakes DoP for actual PCM. So, there is no reason to not allow configuring how to handle DSD instead of just defaulting to converting DSD to PCM.
But I actually had two questions, and maybe there is someone who knows what is planned even for a feature that will only be delivered via a firmware update: If a streamer allows DSD, like the Node Icon is supposed to do in the future, will Roon then allow to configure DoP (even if DoP is not officially supported) to support that the streamer is just used as a digital source?
No it’s not a bug. The Blusound architecture doesn’t support DSD even as DoP in its signal path. The audio routes through a DSP path that cannot be circumvented it’s always through that path even if the options are all defeated for bit perfect and this path is PCM only as all DSP paths are.’
Blusound implement RR to their own specs the device handles. They are not going to advertise it supports a format it doesn’t. To ask Roon to override this is just not what RAAT or Roon Ready is about it, it works to the parameters of that device that the manufacturers implement in their RAAT SDK on the device.
Speak to Bluesound it’s up to them to add support for DoP in their architecture not Roon. I don’t know one device that would work like you want at all. Format support is their for a reason not for a user to circumvent because they think they can and expect it to work as they want.
Neither just a user like you who doesn’t expect devices to work with formats they don’t support.
Blusound is not alone here, Wiim are the same as are most devices that have some DSP or pre dac processing. All these are convenience devices, they have digital volumes, some eq parameters this goes via a DSP path and something in this price bracket is not going to be handling DSD any differently. Some more expensive devices that have DSP have different paths one for DSD and one for PCM but your talking devices into heavy thousands of pounds/euros/dollars . It’s the architecture that defines whether it can handle it or not. Currently no BluOs device or NAD device which uses BluOs hardware cards can pass DSD natively or via DoP.
If you want DSD you can wait and see what Blusound do, but I bet it will accept DSD in but doesn’t pass it through and will internally process to PCM which is pretty much the norm at this price level, but happy to be proved wrong. As to when they release it you may be waiting a long time or it might be quite quick. Having been a BluOs user previously my bets on the former.
If you want DoP switch to a device the currently support it’s such as the Eversolo DMP A6 or even the FiiO SR11.
Absolutely, what you suggest solves the problem I already know that. But this is not a viable solution for me, as the Roon Server is normally located somewhere else.
Up to now, you just told me about the status quo, which is irrelevant. I know the status quo, I tried it - that is why I opened this Roon topic, to question it. And I also didn’t ask about which devices on the market have separate paths of PCM and DSD, because this is also irrelevant as the Bluesound does not need to be aware of DSD at all. And this is not a question about Bluesound devices in particular, either, I just happen to have one - the question applies to any Roon-ready streamer that does not support DSD. It is a question about why Roon deliberately prohibits an option that makes sense. To see why, here a stepwise explanation:
DoP is not a format, as you claim, it is DSD that looks like PCM. So, to a DAC that is not aware of DSD (or DoP for that matter) it is PCM, and it will handle it like, surprise, PCM. That is the way how DoP was designed.
For a Roon-ready streamer to pipe DoP thru to its digital outputs it does not have to know DoP or DSD, because DoP looks like PCM to that streamer. Consequently, the streamer just handles it like PCM, nothing more, nothing less. Which is, among other things, streaming it to its digital outputs.
Such a streamer will produce a low volume noise over its analog outputs (if present) if you care to listen to them, because it does not know about the stream not being actual PCM. Again, this is how DoP was designed: Not damaging anything that is not aware of a PCM stream not really being PCM. But DoP.
Point being: DoP is not a format a streamer has to explicitly support, as you claim, if it is not meant to play something meaningful over its analog outputs if any. That is the whole point of DoP. Et voilà: I’m not interested in that. I just want the PCM data (that sometimes really is DoP) piped thru to the digital outputs. The Bluesound Node would do that out of the box, because it ‘thinks’ it’s getting PCM (it’s never a bad idea to make an important point five times, I’ve been told). It is just that Roon does not allow me to configure DoP for a device that does not claim that it supports DSD (or DoP, or both, I don’t know). Which I wasn’t after in the first place. Because the DAC connected to my Bluesound Node can make sense of a PCM stream that is really DoP. Problem solved. If Roon would just allow me to.
So, this wasn’t so difficult, was it? Here is the DoP spec for your further enlightenment: https://dsd-guide.com/sites/default/files/white-papers/DoP_openStandard_1v1.pdf. One of its key sentences is the last one in the abstract: “While this method is mainly targeted for USB links it is
general enough to be applied to other PCM based links such as Firewire, AES/EBU, S/PDIF etc.” Which is what many devices that understand DoP actually do: They don’t differentiate, with regards to recognizing DoP, over which digital input the signal arrives, they just recognize DoP from any input, unpack the stream to DSD and convert it, by whatever means, separate paths, converting first to real PCM, it does not matter.
If Roon would deliver DoP, then Bluesound would be compatible with it, in a way. At least it would ‘think’ so, because all I need is that it ‘thinks’ that DoP is PCM - which it does.
Your are correct my terminology was incorrect it’s not a format but it still doesn’t change anything.
Does any other software platform or even manufacturers own software send DoP streams to streaming devices that don’t support them? If so please list them.
Roon does not nor will it send unsupported transport streams or file formats to a device it’s why it decodes all pcm based files to PCM and sends DSD as native or encapsulated via DoP.
The support of these methods is down to the manufacturer when they build Roon code into their device not for Roon to say hey let’s ignore that and do this. For Roon to change this goes against its entire principles as to why it built RAAT.
Now if it’s so simple why doesn’t every device support DoP as a transport as they all support PCM. If it would work out as easy as you say it is then every device would support it. But underlying architecture in their hardware do not.
So I am done here it’s going nowhere . If Bluesound add support for DoP and DSD pass through then Roon will support it until that day arrives it won’t.
This is also not a support request it’s a feature request . @moderators pleas move to appropriate place
The answer to your first question is probably: They would send DoP if you ask them to do so simply because they have no idea of the capabilities of the connected DAC in the first place. This again is why DoP was designed to not blow anything: to guard against user error, such as accidentally sending DoP to a DoP-unaware PCM DAC.
Roon is an exception to that in that devices can communicate, via RAAT, their capabilities to the software, as you say. Other than Roon you will only find proprietary protocols doing that. And this is really one of the things that Roon was invented against: all those proprietary micro-verses. I would be interested in what options Roon offers with a device that is just Roon-tested (and thus unable to communicate its capabilities, I assume)?
You’re probably right regarding the feature request - although I would argue that it is rather the option to override a security feature, effectively leaving it away, but I don’t want to be nitpicky
Absolutely, I think so, too, because up to now I don’t see a rational argument as to why Roon should not always be capable to send DoP to a DAC just saying it’s PCM (but not explicitly saying it’s not DSD, as probably most pure PCM DACs will do) - at least after a short warning that this may or may not work, and sound peculiar in the latter case.
You’re right, that’s what T+A’s spec says. That’s why this morning I sent an email to them asking. But even if it only works via USB, the new Node Icon could be a remedy (depending on what it tells of its capabilities via RAAT) because it offers USB as digital audio output. The latter will, with a firmware update, also be true of the new ‘normal’ Node (N310) although it does not ‘understand’ DSD itself.
I think you misunderstand the primary intent of DoP. The primary intent is to get DSD into a DAC capable of decoding DSD. Traditionally, people cross convert DSD to PCM prior to streaming it to their DAC if that is their ultimate intent.
I know the primary intent of DoP from the spec. But a thing may have a primary use case but due to the chosen solution lend itself to other use cases as well. In addition, my particular use case of a streamer with an external DAC (which then understands DSD) is quite common in the High End with its love for separate boxes.
