Cambridge Audio CXNv2 upsampling everything to 384Khz

Audio Gear Talk Cambridge Audio
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Just jumping in to report my frustration today having spent an afternoon at a friend’s house I was visiting and I introduced to Roon some time ago, trying to get a Lossless chain out of his PC-core to Cambridge Audio CXN (V2) to Cambridge Audio CXA61. It drove me crazy as Roon was reporting that upsampling was defined by my PSD settings, which I kept double-checking they were OFF, and couldn’t figure out what was wrong.
Now, much later, with a bit more time, I find this thread that sheds some light on the matter.
In the video above, CA make clear that CXN (V2) is upsampling everything always, regardless of the resolution and type of file fed, stating it’s for the better. And this feature CAN’T BE TURNED OFF.
I just wished they’d let US choose what we like depending on our systems and preferences, by simply adding a switch to turn ATF Upsampling on or off.
Me, in my Roon system, I prefer seeing my lossless chain, and if I want, add PSDs to it to my liking.

Further and more importantly, I believe this feature (or lack of) deprives us of the chance of being in a lossless (without introducing other variables) environment and better able to tell differences and pick the best version of the same tracks (thinking to Qobuz/Tidal) when available in different resolutions. Am I right?

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I thought the upsampling was only if you were using th CXN as a DAC. If you are using digital pass through, I do not think the pass through is being upsampled. I think the device is reporting such upsampling even it if is not doing it on the digital pass through, in error.

But, I would suggest firing off an email to CA support and asking them directly. After the holidays, of course.

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As far as I know that is correct my headphone Amp shows the source sample rate and does not show up sampling

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We’ve also tried the digital output. Roon always displayed the signal as upsampled to 384KHz, hence Enhanced (and non-lossless). There was no way to tell what res was actually reaching the amp (CXA61), but from a pair like the Cambridge Audio and Roon, and the amount of tweaking allowed in Roon, I would expect to be able to monitor everything that is going on from the Roon display, trusting it’s reliable.
Sorry, but I consider this a flaw in design by Cambridge Audio (even if they consider it a feature). They should have allowed turning upsampling off.

In any case, I want to use USB, which doesn’t have the limitation of Coax and Toslink, but the Cambridge Audio CXN doesn’t have a USB out (in only). This prevent to use the CXN 8V2) as a true network bridge

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My belief is the issue is the CXN cannot differentiate between being used with its internal DAC or with an external DAC. But I think it has been proven that it does upsample to the internal DAC but not to its digital output. Obviously the confusion here is that Roon will tell you what it is doing to the internal DAC but you have to ignore that if you use an external DAC. Not ideal.

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@Henry_McLeod

exactly, far from it

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I have noticed this behavior as well and find it too very confusing. I had several dacs connected via spdif and the signal was bitperfect but roon always shows the signal path of the analog output… design flaw? absolutely.

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Cambridge Audio have been producing high quality DAC’s for at least 10 years. The 384 upsampling is a part of their design since then in order to achieve the best audio output from their product / DAC chip combination and this has been since the early DAC Magic 100 and 100 Plus. I am not sure how any one is qualified outside of CA to call this a design fault. (see video explanation at the top of this thread)

If they allowed the upsampling to be switched off then they would be accepting a lower quality output, that is assuming upsampling improves quality. If not why do it ? They produce a HI Fi Component range not designed for user “optimisation” , maybe every manufacturer should allow tinkering on its products (I think not)

If you object to CA’s designs then don’t buy them (eg.I hate Toyotas …).

Its all been said above but the CXN (V1 & V2) uses upsampling only on digital signal destined for the CXN analogue output ie. going to the internal DAC. Any signals going to Digital Inputs (USB., Coax or Optical) and subsequently to a DIGITAL output is unchanged.

Why should CA provide a USB out , its a streamer DAC component product sold as such its not designed to be used as a “Bridge” , it gives digital output options should you really need them. Presumably they believe their DAC is good quality so why pass it to another DAC.

If you use the CA StreamMagic app you see exactly what is going on , there is no report of 384, the CXN limits at 192 on Coax and USB (Class 2) and 96 on Optical. So any 384 input would be downsampled to 192 anyway.

I connect a DNLA server to my CXN V1 (ie not Roon Ready) and then Coax to my M-DAC which I use as a headphone amp (so yes I use it as a bridge) The M-DAC reports exactly the same sampling frequency and bit depth as the DNLA source and the Stream Magic app. If the CXN has design fault it is not providing a headphone socket when i asked they explained that their design philosophy means that amps have headphone sockets not streamers. They revised this thought with the Edge NQ and the new EVO range.

What Roon is showing is what is reported back by the device , if there is a flaw then that is it , reporting the input to the DAC rather than the input to the “Box” , but not the companies design concept for achieving the best sound quality they can.

Yes I have been a CA user for 10 years (PS no affiliation), and happy with the “Black Box” approach they take.

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AFAIK are NOS DACs a rare species. Most DACs (all integrated DAC chips?) do over-sample. It just does not get advertised.

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Make a restore of the firmware of your CXNv2. It looks like that you miss the roon-ready software on your device. I had this problems too with my Edge NQ before the roon release of Cambridge 2020.
Hope this will help you
Egon

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Whatever Roon reports in your path through scenario is not what happens in reality. If you feed up to 192/24 via Roon to the CXN v2 or the Azure for that matter, it will be pushed unchanged to your DAC via Digital out. What does your DAC report when fed a 44.1/16 pass through stream from a Roon source?

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That was 2 years ago there has been Tidal Connect at least since then in March 2021.

Its hard to miss a update as a screen on power up needs a manual adjustment of the selector knob, you can’t do it from the app.

CA are quite active in keeping their products up to date

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This was my main reason for side stepping the cxn v2 in the end. I didn’t like how it handled the inputs, in spite of otherwise looking like an excellent product.

Ended up going matrix audio element I instead.

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I purchased the CXN V2 before I even knew about roon, audirvana and rasberry pi solutions… but I have to say I don’t mind the upsampling or the old DAC chip.

I don’t have any DSD files and I mostly use Qobuz, Tidal through roon.

I let roon upsample to 192khz and the CXN V2 does the 384khz step.

I compared the CXN V2 doing this through roon and the SMSL D300 upsampling through roon to up to 768khz.

Headphone amp Singxer SA-1 and headphones Aeon Noire.

Pretty sure in a blind test I wouldn’t notice what DAC is playing.

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Does this occur when using the CXN as a roon endpoint and its internal dac?

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Thanks. I’m not a fan of that. I like to have choices.

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They have decided its for the best sound for the dacs they use in their kit. I think they likely know what works best for their designs. All DAC chips oversample before the D2A stage and it is likely that these perform better when they are not performing the oversample themselves and it’s done prior. Only NOS dacs don’t oversample and those tend to be discreet designs.

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I wonder if Cambirdge is better or if Roon is better for upsampling,

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It will use a dedicated chip to do it I imagine. Naim have a similar approach they offload the oversampling and digital filter to an Analogue Devices SHARC processor then this allows them to feed into the DAC at a much higher native rate that it can support and improves their performance if they didn’t the DAC would be limited to 96k and would perform the up sample it’s self, this way it allows much higher sample rates and takes the load off the DAC in much the same way Roon or HQPlayer are supposed to do. But oversamping and upsampling are not the same process.