Nucleus+ Dropping When Upsampling to DSD512 Using Qobuz & Fios

Roon Core Machine

Nucleus+, v1.8

Networking Gear & Setup Details

Verizon Fios 1gbs: G3100 > coax > E3200 > Cat8 > Nucleus+

Connected Audio Devices

Nucleus+ > PineTree USB > Denafrips Ares II

Number of Tracks in Library

677 tracks

Description of Issue

Experiencing drop offs every time I try to upsample to DSD512. Music plays for 1-3 minutes before dropping. Nucleus+ is brand new. Ethernet speed has been verified as advertised. Yet processing speeds are no greater than 1.3 when upsampling. I’ve read as many posts as I could find and while some touch on this, none provide an answer or solution. My set up is clean. I did not expect the Nucleus+ to struggle with this given the DSP claims. What am I missing? Please advise.

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Did you try a lower DSD rate, such as DSD256? Just wondering if the Nucleus is going into thermal throttle because of the upsampling and SD modulation load. For context, I use HQPlayer on a much beefier server, with fan cooling, than the Nucleus+ for SDM conversion to DSD256 and that uses 50% of the server’s CPU capacity.

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The processing speed is 1.1 which is really borderline as it isn’t really a constant number so might occasionally drop below 1. If you haven’t already done so go into DSP and enable Parallelize Sigma-Delta Modulator. Roon uses a single core by default and this allows it to use two for a bit more power at he expense of some efficiency. Otherwise your only options are to reduce to DSD256 or add another powerful PC with a HQPlayer licence and go through that learning curve.

@2000W had done it already, see image on the first post of the thread.

I’d imagine its the latency from it being streamed via the internet. Processing speed isn’t just cpu as Roon have explained, it’s the whole chain of how quickly Roon can process the files in real-time. Local files on the core compared to files from a Nas or other server can affect speeds I imagine from streaming it has an overhead in Roon
to At this higher DSD rate you have less Room for any slight variations as you likely at the top of what the Nucleus can do in this regard. Just because you have 1gb fibre doenst mean you always have a great connection all the time and different services will fluctuate. Roon is very sensitive to any latency. Try a local file and see if you get the same behaviour, try changing the DNS servers in your router to 1.1.1.1 or Google as you ISP might not be routing you the optimal route. Or as the others have said you have reached the max it can do.

I can upsample to DSD512 on a similar processor to the N+ Infact it’s a little lower. Local files have a better processing rate over Qobuz it’s not much but if your already borderline which anything under 1.5 is then it will likely suffer. This is over WiFi to my endpoint so would be better if wired as wireless also adds latency. I can’t test from my core to Dac as my ADI doesn’t do native DSD via Rock.

Checking internet download throughput during playback of streaming content, you’ll see a massive spike while Roon caches the respective file in one big chunk using maximum bandwidth at the beginning of each song - latency has likely no relevance to the OP’s problem occurring minutes into the song.

Maybe give unshielded Ethernet cable a try, @2000W, as that’ll eliminate a possible ground loop problem, which might not even cause audible interference, so stayed under your radar…

From what I can find online at face value, give it a shot and test with a bog standard USB cable - boutique solutions rather tend to introduce more problems than gain audible improvements …

Yes, just looked properly while wide awake! I did scroll back earlier but never got beyond the second image!

I have tried DSD256 and processing speeds increase to ~3.0. Still seems low compared to signal paths of other posts.

@CrystalGipsy appreciate the suggestions. I will investigate. Curious that you can upsample to DSD512 using a slightly less powerful processor AND do it over WiFi compared to my machine struggling with Ethernet and a more powerful processor. Seems like I must doing something wrong. After all, why would Roon market their top of the line product as being capable of all DSP variations (this was one of the reasons I bought the Plus over the standard machine) but not actually equip it with a powerful enough processor? That would be a real head scratcher - so I will continue to explore solutions.

@Marin_Weigel thanks for these ideas. I did try the unshielded Ethernet cable previously and doing so actually reduced processing speeds slightly. I actually called Jesse at PineTree to discuss the Cat8 and how that could be part of the problem. He walked me through the same grounding issue but said I would know if it weren’t working because the data wouldn’t be running through. In any case, given the above experiment, I think we can rule out that cable for now.
That said, I have not tried an alternative USB so will definitely try it. To be sure, I use PineTree products throughout my system - from from their shadow ribbon speaker cable to their iso braided xlrs - and think highly of and recommend them. But won’t be biased in evaluating the USB.

The N+ covers most usual DSP situations but it wont cover every situation its still too general purpose for that as you need a much beefier deskop CPU for really heavy duty tasks. DSD upsampling is one of the most taxing processes Roons DSP does, but I am surprised its not working on the N+ to 512 I dont expect it to cope with higher. If you wanted DSD512 upsampling plus say Convolution then the Nucleus is definitley not up to the job.

@Fernando_Pereira thanks for your insight. I’m curious about the HQPlayer and if it would enhance my setup. Why do you use it and how has your experience with it been.

@CrystalGipsy I am surprised too. Not sure about Convolution though as I’m not familiar with it. Am guessing I’m not attempting it.

No its to apply eq filters, usually used for Room Correction EQ. I use it in two zones. I dont bother upsampling myself as I hear no benifits with my systems.

Don’t forget, we’re talking completely different domains here, namely analog and digital signal transfer - the former’s rules do not apply to the latter!

I use HQPlayer on one of my headphone systems: PCM>DSD256>Holo May KTE>analog components. HQPlayer is very flexible but also quite complex, much more than Roon DSP. The May is a great DAC even in PCM NOS, but with the right upsampling filter and SDM modulator in HQPplayer, which has many options for both, it’s even better to my ears.

I’m not disagreeing with you, in fact, I do agree DSD512 is really taxing, but Roon does say on its nucleus+ product page that it works with “All DSP functions available”. As a customer, I’d expect it to work.

@CrystalGipsy Understood on SQ but I want to be able to find out!

@Marin_Weigel Fair point indeed. Just ordered a generic USB and it arrives tomorrow. Will update on the outcome of the swap.

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The issue is the processing speed. I have found that anything less than 1.3x can run into playback issues.