While it is possible to let DSD untouched by the upsampler while working on the other signals, I don’t think it is possible to do the same for DXD.
Would it be difficult to implement ?
Hi,
If you have a Vivaldi Upsampler then I think what you are looking for is called “Clone Mode” (Page 38 of the Vivaldi Upsampler manual) - that will allow PCM to be passed through untouched.
Best Regards
Phil Harrs
Hello,
As far as I know, clone mode will not specifically leave untouched DXD but any flow. My request is more specifically for DXD. My understanding of the DSD Pass-through is that it allows for DSD to disable processing when it does not make sense i.e. the source is “good enough” and your output is some PCM level (so I guess usually DXD)
I believe a similar statement could be done for DXD for people that want to upsample to DSD or DSD2 for most flows but consider that DXD “on its own” is “good enough as-is”…
I hope I am more clear 
Phil, is there a plan to provide Clone Mode to Rossini Apex Dac in future?
Regards,
Sourav
Hi Sourav,
Clone mode isn’t really applicable to the way that the Rossini works - it is there primarily as a function of the physical separation of the Vivaldi Upsampler and the Vivaldi DAC.
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Hi Phil,
I understand your point ‘it is there primarily as a function of the physical separation of the Vivaldi Upsampler and the Vivaldi DAC’.
But as a functionality, will there be a way in future by which end user can avoid any kind of upsampling in Rossini ?
Regards,
Sourav
Hi Sourav,
Upsampling is an inherent part of the dCS Ring DAC and how it works so there will always be an upsampling process.
Cheers
Phil
Hi Phil,
In that case I am curious to understand how upsampling can be avoided in Vivaldi dac assuming that Vivaldi dac also uses same dCS Ring Dac as in Rossini dac.
Regards,
Sourav
Hi Sourav,
The simple answer is that it can’t but by using clone mode you can determine whether the bulk of the upsampling is done in the Upsampler or is left to the DAC.
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That makes sense.
So does that mean using Cloning model in Vivaldi upsampler one can push majority (or all ?) of the upsampling to the Vivaldi dac ?
Regards,
Sourav
Yes but generally it’s better to let the Upsampler do the bulk of the donkeywork…
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Hi Phil,
Thanks for clearing a doubt I had for a long.
It clears up the miss conception that in Vivaldi one can avoid upsampling by using Clone option. This option only allows to push the up sampling to Dac instead of doing the entire upsampling (or part of it) in upsampler.
Regards,
Sourav
Sourav,
Vivaldi DAC displays the bit depth and sampling frequency of the data it is actually receiving.So you can check what I say in situ if you have a Vivaldi stack.
With a Vivaldi Upsampler and with Clone Mode selected in Mosaic an (e.g. 16/44.1) datastream source will be received by DAC as 16/44.1. If , however, Clone Mode is not selected and even if Upsampler sampling rate is selected to be the same in and out ( in this case 44.1), the 16 bit output will still be padded to 24 bit.
So, in short ,with Clone Mode 16/44.1 in = 16/44.1 out .Without Clone Mode 16/44.1 in = 24/44.1 out ( if upsampling in and out are effectively selected to be at the same rate such as 44.1). With Clone Mode any other data data rate stream will also be sent to DAC at the native rate and will neither be upsampled nor have bit depth padded.
If I remember correctly Clone Mode was originally introduced so that HDCD data sent via the Upsampler could be passed to the DAC intact.
Incidentally I do not know about Rossini but we seem to have moved to Vivaldi in this thread.
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Hi PAR,
I dont have Vivaldi. However, I dont see anything logically wrong in your observation.
But, if I understood what @Phil has mentioned above, even if u send a 16/44.1 to Vivaldi dac in Clone mode, the Vivaldi dac would first upsample it.
So what somebody is able to avoid in Clone mode is avoiding upsampling in Upsampler and pushing the same task to Vivaldi dac. However, it seems to me that anyway is not a very good idea based on what mentioned by @Phill above ‘it’s better to let the Upsampler do the bulk of the donkeywork…’.
So, in summary, to me -
Logically any 16/44.1 input to a Vivaldi Upsampler + Vivaldi Dac system will go through these 2 conceptual stages -
Stage 1 (Upsampling) + Stage 2 (Other necessary processing for DtoA)
1.Option 1 : Clone mode on - Vivaldi dac is doing both Stage 1 and Stage 2 for a 16/44.1 input fed to the upsampler
2. Option 2 : Clone mode off - Upsampler is doing Stage 1 for a 16/44.1 input fed to upsampler. Upsampler is then providing the Vivaldi dac the upsampled data and the Vivaldi dac is doing Stage 2.
In Rossini, the same logical architecture prevails. It is just that since Rossini is not a 2 box solution, separating Upsampling from actual DtoA conversion, one cannot have Clone mode there.
@Phil I hope my above understanding is correct.
Regards,
Sourav
Which is why I am asking if at some point they can let specifically DXD free from upsampling/conversion to DSD. At the end it is already at the max a Vivaldi upsampler can do…
Clone mode selected impacts all signal and cannot be specific and as such is not a solution (unless obviously you are ready to change the mode each and every time you present a DXD source and leave it)
It is eventually just a bypass like DSD mode.
Hi,
There’s a set of articles written by James which explain in detail how the dCS Ring DAC works which is here and may help to cover your question - certainly very worth a read…
Best regards
Phil
Not sure if I misunderstood your posts, but the Vivaldi Upsampler does not upsample DXD to DSD, if you don’t want it to.
With “Clone Mode” OFF, “DXD Mode” to ON (Locked), “DSD Pass-Through” ON, and the Upsampler’s Output set to DXD; all incoming DXD sources are output as DXD, while incoming DSD is bypassed from any conversion and remains as DSD. Both with Filter 1, the classic sharp filter applied. Incoming DXD is only converted to DSD if you specifically set the Upsampler’s Output to DSD/DSDx2.
@Phil perhaps the real question for the VUP is; (aside from Clone mode) when the incoming source rate and the output rate are the same, obviously there won’t be any interpolation going on, in which case, is Filter 1 even necessary? Or does it just have no effect in cases of I/O rates being equal?
Just for kicks, I checked the Scarlatti Upsampler Manual, it has this interesting nugget;
Filter 1 is a classic sharp filter. The 44.1k → 44.1k conversion has no filtering, the level is reduced by 0.1dB.
The behaviour in the Vivaldi Upsampler is the same as in the Scarlatti Upsampler when I/O rates are the same. The output volume is attenuated by 0.1dB to match the 0.1dB attenuation incurred during interpolation (filter ripple). It isn’t strictly speaking a filter - the connected DAC always has to do its own filtering, the same as if the Upsampler was not in the chain, so no use doing it twice as you suggest.
(on a completely unrelated note, the 0.1dB attenuation may actually help with intersample overs if they are present in the recording)
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Thanks for the response James, makes sense. I never really thought about it till this thread as I always Upsample 
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My point was precisely to request an exception for DXD when regularly you upsampler to DSD/DSD2. For sure in clone mode it leaves the upsampler unchanged but it means enabling clone mode before feeding the upsampler with DXD stream and removing it after. We have such “bypass” for DSD, why not for DXD? At the end, it is already at the “max” resolution of what can output a Vivaldi upsampler.
Anyway I am quite sure that by now Phil understood what I meant and it is probably stupid as he politely avoided to really answer.
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