Pro-Ject Pre Box S2 Digital

(Sean) #626

Thanks Govnah.

I don’t think you are actually up-sampling to DSD256 though while you are seeing MQB on the DAC’s display :disappointed_relieved:

Check your DAC’s screen for the incoming sample rate.

@brian confirmed it’s not possible to do Roon up-sampling (any sample rate conversion) and still see MQB on the DAC’s display.

No MQA signal info is carried through with Roon up-sampling.

(Geoff Mirelowitz) #627

What is “MQB”?

(Armin Kern) #628

no problem, it’s an OLED!

(Sean) #629

The S2 DAC will show MQB on it’s display when it’s functioning in ‘rendering’ mode, i.e. when something else upstream has done the 1st unfold and is still carrying the MQA signal through to the DAC.

Like what Roon can do now, and Audirvana and the Tidal Desktop App have been able to do for a while.

When the S2 DAC is left to do the full MQA decode, then you’ll get MQA on it’s display.

Brian explained it better in October further up this thread:

Hope that helps.

(Geoff Mirelowitz) #630

Thanks very much.


Will S2 be controlled by Roon in terms of volume up/down?

(Magnus) #632

It can be, depends on volume control setting in Roon.

(Philo Melos) #633

Bought the Pre Box S2 Digital a couple of days ago. Nice Little Dac. I play it connected to a NuC (Win 10) or the USBridge. Unfortunately it give’s drop-outs when playing MQA music in Roon, no matter what settings I use, both with USBridge or Windows 10 NuC. The drop-outs are at the beginning of every new MQA track. More people expierence this behavior? It’s kind off useless for MQA this way, and that’s a shame. (It got the newest firmware 2.12)

(Sean) #634

This is a known issue when the S2 is doing the full decode. Pro-Ject have been aware for a while and working on a fix.

But I never had any issue when Audirvana or Tidal Desktop App or now Roon do the 1st unfold.

Can you share a screenshot of your signal path when Roon is doing the 1st unfold?

And are you seeing MQB on your S2 DAC’s display and still hearing dropouts?


(Magnus) #635

I use DSP (room correction) which makes Roon do the first unfold, and it seems to remove that stutter you describe. So if you tell Roon to do the first unfold, which I think you can do by setting the DAC as a Renderer only, it should fix the problem.

(Magnus) #636

Or you can set MQA dac capabilities to No MQA support, which will make Roon do the first unfold, and then you can upsample to whatever you like in Roon. You won’t get the second MQA unfold then, but that unfold is basically an upsample so you won’t miss much.

I am experimenting with this myself now, upsampling to DSD512 after first MQA unfold is kinda cool :slight_smile:

Here is the signal path:

(Philo Melos) #637

I changed setup, letting Roon do the 1st unfold. There is still a tiny click at the beginning of each track, but much better than before.
Just gonna wait till the fix comes out.

(Philo Melos) #638

Thnx. Gonna give it a try someday.


Hi Magnus. Works for me too with the first MQA unfold by Roon. However, when trying to upsample to 512 for S2D in Roon via DSP, I only get the option of going to 256? Anything I miss?

(Magnus) #640

You need to use the ASIO drivers, and set DSD playback to “Native” to be able to play DSD512. Or use DSD256 and don’t bother with 512, I don’t hear any differences between them.


Got it. Thanks. I’m on a Mac. Probably that’s why I don’t see that option.

(Geoff Mirelowitz) #642

Thanks for that information on the S2 Digital drop out issue. I’ve been thinking of purchasing it but that’s a problem I don’t want to deal with.

(Magnus) #643

Its only for MQA and its not a dropout, more of a quick stutter. Still, its a little annoying which is why I let Roon handle MQA and upsample manually, which means no stutter and better sound. And the core problem seems to be with MQA libraries inside the DAC, since some other MQA DACs also have this problem.

(Nick) #644

I use a sync delay in Roon settings to fix that issue. Seems to work fine.

(Geoff Mirelowitz) #645

I get all that. But my only reason for considering the Pro-ject is for its MQA capabilities. I have hoped it would be an upgrade of my Explorer 2 DAC.

With the problem you describe, I would not consider that an upgrade. The Explorer does very well. FWIW earlier this year I purchased a Meridian 218 zone controller. Bot the Meridian rep and the dealer said the DAC performance from the zone controller would be noticeably better than the Explorer. After a month I decided whatever difference there was, is one I can’t hear. So I returned the zone controller and stuck with the Explorer.

I also have a Bel Canto 2.5 DAC that does very well with non MQA files.