Problem upsampling PCM to DSD 512

I am very disappointed with my brand new Nucleus Plus. I can’t upsample PCM to DSD 512. First the Nucleus is very slow when switching from different tracks on my queue. But most important after playing music for about 2 to 3 minutes I get drop outs and the music fades out. I am using the Nucleus + as a Roon core attached to my network with ethernet. I used to use a PC with an i3 processor and had no problems with DSD 512. The processing speed now is a low 1.1x . I tried 2 different DACs with the same result so the problem lies with the Nucleus. If I try DSD 256 there seems to be no problem. Also if I use DSD over DOP rather than the native DSD option, the upsampling appears to work but I am limited then to DSD 256. Is my Nucleus defective or is there a simple fix?

According to there web page it states all All DSP functions available.1.1 speed is slow.

Make sure you Parallelize Sigma-Delta on in DSP settings

Grab 2021-06-17 at  13.21.19

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While all functions might be available it doesn’t mean you case them all to the maximum or in multiple combinations - there is a limit to how much combined processing as available.

ie if you are also simultaneously importing or analysing music this will not be possible

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@wizardofoz I have the settings as you have indicated but still unable to upsample to DSD 512.

@wizardofoz I am not doing any other functions at the same time just trying to upsample

@outlaw I agree with you. Something seems to be wrong.

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Can you post a screen shot of the Signal Path. What were the DACs used? Also some things to investigate:

  1. is the system still going through Audio Analysis? You mentioned it was new. To be sure, go to Settings/Library and Set Analysis to OFF to make sure.

  2. Verify that you are doing any volume leveling (which is DSP).

Hi @buffalo

As suggested above, a screenshot of the Signal Path would definitely help here. Can you confirm how many albums total are in your library as well? Thanks!

@Rugby I turned the Analysis to off with no difference. Still can’t upsample to DSD 512. The only DSP I am doing is sample rate conversion. My main DAC is the Holo Audio May. I also used the Topping D70 with the same problem as well.

@dylan I have 27 albums in my library. The Nucleus Plus is less than 1 day old.

I want to re-emphasize that my i3 PC upsamples to DSD 512 with no problem.

Hi @buffalo

It’s possible that analysis is still being performed at the moment which uses some resources that would otherwise be available for heavier DSP operation.

If you go to Settings > Library do you see that analysis is running? Is there any improvement if you set background analysis to off?

I turned off the analysis. I got a slight improvement but after 2-3 minutes into a song the dropouts begin and then the music fades away and stops.

What is your audio Chain? I am assuming it is:

Nucleus > usb > Holo

Using the Nucleus as Roon Core, attached to network via ethernet. SoTM SmS-1000SQ server as Roon endpoint. Holo Audio DAC via USB

I would suggest removing the SotM to test, and just going Nucleus to Holo via USB and see if you get the same slow down. That way you know that either your network or the SotM isn’t interfering is some bizarre way.

Not really interested in doing that since that is not the intended use. My Nucleus is in another room away from the Holo and the main audio system. I appreciate all the help but this is just not going to work out. Doing a search, other discussions on this forum have also described what I am saying with low speed processing rates. So this is not unusual when trying to get upsampled DSD 512 with the Nucleus Plus.

I will send the unit back for a refund.

Something is wrong with your SoTM SmS-1000SQ I bet … I’m using a Nucleus (RevA) i3 non + unit, and I can get 1.5X upsampling from Qobuz to Native DSD512 direct USB from Nucleus.

Remove your SOtM from the chain and see what happens.

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Hi @buffalo — I’ve reached out via PM.