DAC: Rossini vs Vivaldi

I know it’s not possible to disable upsampling on Bartók or Rossini at the moment, but is this something that would be possible in a future software update?

It sounds like it’d be a nice option to have.

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I believe dCS see upsampling as a particular strength of theirs so I doubt it. I don’t see why not though.

allow me a stupid question…I have a Rossini, where do I see that there’s an upsampling? Did I enable that?

As noted above, it is an integral part of the presentation. It is not an option. Nothing to enable, and not defeatable.

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Although as Greg says upsampling is always engaged in Rossini you can choose what type of upsampling you want. You have a choice between DSD, DSDx2 or DXD. You can select which in the unit’s settings. See page 39 of the user manual.

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thanks Pete! found it :slight_smile:
never thought about that…

Thanks for that clarification Pete. I shouldn’t have taken that aspect for granted.

“Everything presented to a Ring DAC is oversampled, noise-shaped and converted to 5 bits at either 2.822 or 3.07MS/s. This arrangement gives 24-bit performance in the audio band, low noise and a frequency response that extends beyond 100kHz”

John Quick (dCS USA) once mentioned in an email that they were working on a white paper on the Ring DAC that would describe its inner workings (and hence the role of upsampling) in more detail.

@Andrew would you know if there has been progress on this white paper?

Hi,

It would be interesting to understand the difference between oversampling and upsampling.
When a signal, say 16/44,1 is “transformed” into 24/364, is it oversampling or upsampling ?
The question can be asked this way: When Qobuz stream every music in 24/192, shall the upsampling still necessary ?

I found this: https://www.audioholics.com/audio-technologies/upsampling-vs-oversampling-for-digital-audio

But I do not have the technical background to criticize it, however, it was an interesting reading.

As Chris K points out there is a difference between upsampling and oversampling ( the latter relating to the Ring DAC). Many years ago dCS did produce a white paper on upsamplng (which I recall did attempt an explanation of its difference to oversampling). However that white paper seems no longer to be available and, sadly, I no longer have a copy.

Upsampling vs. Oversampling according to dCS, circa 2008;

Upsampling

An Upsampler is a digital-to-digital converter (DDC) capable of converting digital audio data at one sample rate to a higher sample rate. The term “Upsampler” was first used by dCS in 1998 during development of the dCS Purcell. Some other manufacturers appear to have confused the term “upsampling” with “oversampling”, which is a similar process used in good audio DACs for many years. They have missed the point that upsampling is an intermediate step intended to provide enhanced data to drive an oversampling DAC.

Some positive observations that help to characterise the effects of upsampling in a dCS system:

  1. Upsampling to progressively higher sample rates makes progressive improvements to fine detail, sound stage depth and image separation. So, the sound quality increases as you upsample CD data first to 24/88.2, then 24/176.4, then 24/352.8 kS/s.
  2. Converting 16/44.1 to 24/44.1 kS/s makes a worthwhile improvement to the fine detail, so the resolution is important also.
  3. If data with a higher information capacity is presented to the Ring DAC, sonic improvements are reported.

One present view is that upsampling works by breaking the DAC’s oversampling function down into 2 steps, presenting the DAC with finer, smoother data, making the DAC’s job much easier and more accurate.

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…allow me to come back to this topic again…
I have now a Rossini+Masterclock and the option to upgrade(?) to a Vivaldi DAC native without clock etc.
Running a Melco with USB out direct into Rossini, would the same setup (Melco-USB) on Vivaldi sounds better?
thanks folks!

If you want anything to sound better do not use the USB input. Network connection is best particularly with Melco as server.

Vivaldi DAC should sound better than Rossini DAC plus clock but in your proposed scheme you would have no network connection as in the Vivaldi system this port is on the Vivaldi Upsampler. You would therefore need to connect from Melco with USB and use their control application not Mosaic.

This means ( at least to me) that changing to Vivaldi without other Vivaldi components may not be the best thing to do. You will need to carry out your own comparison. My expectation however is that Rossini/Rossini clock with Melco connected by a network cable ( unshlelded please) using Mosaic may put up a very good fight. I have used Vivaldi DAC ( with Vivaldi Clock) fed from a USB source and thought it was pretty good until I changed to network connection which was a bit of a revelation.

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Pete,
MANY thanks for this info! Helps a lot!

I had a dCS Vivaldi Dac connected to a Network Bridge, connected via the RJ/45 port to a NAS…it worked great !
Now I replaced the NB by the Vuvaldi Upsampler, it is even better, but thanks to the NB I started with the Vivaldi Dac…which is way better than the Rossini/clock…In my view…

Thanks Chris, but the DAC and the Upsampler is out of my reach :wink:

I do understand that, it wasn’t possible for me either…that is the reason why I did it in two times Dac+ NB and two years later I bought the Upsampler.

Rossini + clock is not that far from Vivaldi Dac + NB…pricewise…:laughing:

The problem with Rossini is that it is in the middle…some would say it is the sweet spot…but is there any sweet spot in listening music ?

Well, if as soon as you buy a piece of gear you watch for something better…was it the sweet spot ? And rhis happens a lot when you read this forum…

The advice "never stay in the middle " often valid in management might be valid too in hifi :wink:

But we are talking about details, actually the Bartok is already excellent, Rossini and Vivaldi are better, but at a cost :scream:

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Chris I think that ought to be in the past tense as NB is no longer produced. So that interim stage that both you and I pursued on our way to Vivaldi Upsampler has gone making the short term financial implications of moving to Vivaldi of greater impact.

Pete,
that means - since NB is no longer available- the only “valid” option is DAC + Upsampler, right?

For Vivaldi yes . Vivaldi DAC has only the function of digital to analogue conversion. Upsampling and network processing functions are contained in the separate Upsampler. Of course Rossini has all of the functions in a single chassis.

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