Is upsampling done via Roon controls or HQ Player?

In Roon, headroom adjustment can be set separately from the software volume control. In HQPlayer, the software volume control also supplies headroom adjustment. If desired, you can set the HQPlayer volume control to max out at, for example, -3 dBFS. That is de facto headroom management.


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I am assuming DSDFF/DSF refers to the Direct SDM enabled, like so:

which means DSD is passed through with no conversion, and so it’s that DSD128 limit again.

Thanks, Andrew.

Will volume leveling set in Roon pass thru HQP to provide volume leveling in HQP output? Because of the significant variance in HQP volume track to track, it’s something that would be attractive to me.

Thank you

Thanks Lorin. It’s curious because theDSD64 upsamples to 128 in this set up, but DSD256 does not downsample to 128? Instead, just doesn’t play.

Ok, it is what it is!!

Thx again.


That depends upon what you mean by “pass thru,” Bruce.

Roon and HQPlayer can communicate with one another to keep a single software volume control in sync. Change the volume in Roon, and it actually is the HQPlayer software volume control that performs the adjustment. Similarly, change the volume in HQPlayer, and Roon reflects the change. But to my knowledge, that is about as far as passthrough communication goes.

So, any volume leveling set in Roon will be performed by Roon DSP. HQPlayer will have no role in the operation. But once a digital signal has been volume leveled, that attenuation is a mathematical alteration to the signal that will carry downstream.


Got it. If I want Volume leveling, enable it in Roon and I will get it. Perfect. Thank you.

Sorry, this isn’t correct. My Roon core is on a Mac mini running MacOS, HQP runs on an iMac running MacOS, and I output to a Linux-based network endpoint. I can upsample everything to DSD256. (That screen grab of my HQP main window isn’t faked.)

If, in HQP prefs, you still have SDM pack set to DoP, that may account for why you can’t go past DSD128. The other possibility is that the software on the ultraRendu doesn’t support DSD256 on the Simaudio Moon 280D. Maybe @Jesus_Rodriguez can weigh in on this?

As soon as I have a moment tomorrow, I’ll post a screen grab of my HQP prefs; maybe that will help.

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Here’s what Jesus told me after looking at the DAC specs identified on the ultraRendu:

This unit does not support native DSD streaming in Linux. You have to use DoP. This unit supports 384 PCM which means you can only stream DoP up to DSD128.

I will play around tomorrow turning the DoP off on the SDM settings and see what happens.

I’m sorry this has turned into a can of worms. Not sure how what he is saying meshes with ur experirnce. My biggest learning so far re: improving SQ is nothing is easy.

Thank you.

The ultraRendu uses a Linux kernel. Linux requires each DAC to have a separate table entry in order for it to be recognised as capable of native (non DoP) DSD. This requires a patch to the ultraRendu kernel, which occurs from time to time. The most you can do is to regularly update the SonicOrbiter software and the next time the kernel is patched your DAC is likely to be included. It may be, however, that your DAC doesn’t support native DSD at all. I couldn’t tell from the manual.

According to this list of DSD 256 DoP DACs you should be able to get DSD 256 DoP, but it might be wrong.

I would go by what @Jesus_Rodriguez says. He’s the best source for what Sonore gear can and can’t do and for analyzing what’s happening with the 280D in this case. To expand just a little on what Jesus said, my understanding is that if a DAC doesn’t support native DSD streaming in Linux, it would have to support 705.6/768 PCM rates to be able to be able to do DSD256 via DoP.

You might want to ask Simaudio about what, if anything, could be done to make the 280D capable of native DSD streaming in Linux.

I’m truly sorry if I contributed to any confusion in this area.

Pretty sure it’s irrelevant at this point, but I said I’d post a screen grab of my HQP settings, so here they are. Maybe they’ll be of use to someone down the road. These work for output from HQP to my exaSound PlayPoint streamer and e32 DAC.

Thanks to all who took time to address my problems, teach and offer encouragement. I’ve learned a lot and applied all to better capitalize on what I have, as well as understand its limitations.

Great help on configuring HQP, appreciating its flexibility and getting suggestions on filters.

Very glad I can use Roon’s Volume Leveling to compensate for lack thereof in HQP. It’s badly needed IMO. Also, good to know, Headroom Mgt. is embedded in HQP Voume Control, so no need to double up by enabling same in Roon.

Very disappointed to learn my system will not play DSD256 in Simaudio 280D DAC. Although still a bit confusing to me, apparently this is due to DAC limitations preventing it from using its advertised DSD256 capability because 1) it does not support native streaming in Linux and 2) has DoP capability only to 384PCM which aligns with DSD128, which it can play. This may not be quite right but what I gather.

Again, it’s very comforting to know there are quality, helping hands here for those in need!



I have the same dac and use windows 10…With Windows and sim audio driver you can native dsd 256.

Thanks. Yes. I was pretty sure that would cure things. I’m pretty committed to the Mac, but will consider exploring. Appreciate your confirming that would solve things.

Are u going PC direct to DAC or do u have something in between?



Use a intel nuc as network audio adapter

Hi Jason. Thx. Don’t know anything about Intel NUC? Is it a new component for my audio chain? Or substitute for ultraRendu?

Jason - the Intel NUC - its like a minimac for Windows?

Nuc is just a small factor pc.They work great as a naa device.


Follow up question. Do you have the NUC hooked up to a monitor? Or is there another way to operate it? My Mac is in a room separate from the rest of my audio system so I’d probably want the NUC - which I’d use only for Roon/HQ Player - with the rest of the audio components. Currently there’s no monitor.

Thanks in advance.


Don’t use a monitor for nuc.I use team viewer to control nuc from a I pad air.Once you have the nuc set up and running there is nothing else to do.