Pro-Ject Pre Box S2 Digital: MQA HW decoding at reasonable cost

[asdf1000]

1 hour ago, Miska said:

Here's a screenshot, but exact settings may vary depending on your preferences and the OS you are using...

 

Many thanks. I'll use this as a starting point and tweak to preferences. I'm waiting for HQP Embedded to hit my sonicTransporter i7.... Supposed to be going live soon-ish.

 

It will be interesting to see/hear if the sonicT i7 can cope with these HQP settings, as well as running Roon Core on the same machine. Only one way to find out - to try it.

[asdf1000]

10 minutes ago, buonassi said:

http://www.pro-jectusa.com/en-us/products/pro-ject-box-designs/dac-s-and-sources/s2-line/dac-box-s2

 

I could just get this if I’m not concerned with mqa, head amp,or having an led display?  Curious how the analogue stage is on this vs the pre.

 

as a stand-alone dac I wonder if this can match the pre sonically. 

 

That one linked is not designed by John Westlake though.

 

That's not to say it won't sound great but I think John Westlake (designer) is a big reason the S2D sounds so good.

 

[asdf1000]

On 06/04/2018 at 7:24 AM, Miska said:

 

For listening I use poly-sinc-short-mp(-2s) most of the time. And ASDM7 modulator to DSD512. So pretty much same as for iFi iDSD.

 

Here's a screenshot, but exact settings may vary depending on your preferences and the OS you are using...

 

Hi Jussi @Miska

 

I've tried to copy your settings (as a starting point). See attached for my sonicTransporter i7 settings.

 

Roon says it's HQP DSD512x48k being played but the Pro-Ject S2 DAC itself display doesn't show DSD512 sample rate.

 

Is that normal? See attached settings.

 

Do you see the DSD512 sample rate displayed on your Pro-Ject S2 DAC unit's display, with these settings?

 

 

 

 

 

 

[asdf1000]

Another question @Miska

 

Is there a way to disable all HQP DSP in a quick way, just to compare the DAC's internal filters vs HQP?

 

And also to compare against MQA.

 

(I wish MQA would go away but since I have this DAC, I might as well listen to hear what all the fuss is about)

 

Roon allows a quick DSP toggle on/off switch.

 

Is there a quick setting in HQP to do the same, to play everything bit-perfect but still keep all the HQP filter settings there when DSP is re-enabled?

 

Cheers!

 

[asdf1000]

5 hours ago, Miska said:

Yes it is normal, S2 doesn't show anything for 48-base DSD rates, only for 44.1-base ones. But as you have noticed also 48-base ones work...

 

Ah yes. When I choose 512x44k then i do get DSD512 displayed. Thanks.

 

Is there any advantage in measurements going to 512x48k ?

 

I’m guessing there’s a reason you do prefer this so there is a difference with 512x44k ?

 

Also I don’t see your CUDA offload and multi core settings as an option - is this not applicable to Linux Embedded?

 

And I don’t see min Vol and max Vol also? 

 

Cheers

 

[asdf1000]

9 hours ago, Miska said:

But there is fixed volume setting if you want to set volume to fixed value and prevent remote end from changing it, and there's a setting for default startup volume setting when you boot up the system (when volume is adjustable).

 

If I use the S2 DAC's digital volume control (never louder volume than -20dB max) then I can safely have HQ Play's volume fixed at 0dB right?

 

I shouldn't have to worry about clipping/distortion at HQP's software volume unless I have the S2 DAC at 0dB?

 

[asdf1000]

2 minutes ago, Miska said:

 

No, the value range of data between HQPlayer and the DAC is still limited and cannot exceed 0 dBFS. So do not turn HQPlayer's volume higher than -3 dBFS, otherwise you will likely end up triggering the limiter. This cannot be "fixed" after-the-fact using DAC's volume control.

 

 

Noted. I'll take further HQPlayer discussion over to your HQPlayer thread, since this is not exclusive to the S2 DAC.

[asdf1000]

Hi Jussi @Miska

 

With the S2 DAC, if using it as DAC only (RCA outputs - not using headphone output) do you recommend having the S2 DAC's digital volume control set to 0dB? Or -3dB? Were all your measurements done at 0dB?

 

HQP Embedded for me is already always set at -6dB.

 

[asdf1000]

Just now, Miska said:

 

Yes, set the volume in S2 to 0 dB. That is how my measurements were done. When listening, set the software volume in HQPlayer to -3 dB or lower. DAC's volume should be left at 0 dB (practically should result in multiplication by 1).

 

 

Thanks!

[asdf1000]

1 hour ago, Miska said:

 

I think I've got some luck with my earlier unit then, it's been running 24/7 (because it doesn't have a power switch) without problems.

 

 

Same for me - not a single issue running 24/7. Fed via HQPe DSD512 via a microrendu  , sounds superb.

 

[asdf1000]

28 minutes ago, left channel said:

The firmware has been a problem throughout.

 

The only firmware issue I'm aware of (as of the current version, after they fixed other issues) is the MQA one which they know about but I feed it DSD512 via HQPe and never had a firmware issue.

 

I may be the exception and not the rule though.

[asdf1000]

56 minutes ago, creativepart said:

I'm not having any firmware issues - I have Roon set up upsample 44/16 to DSD 64 and all else I run through the S2 is MQA. I've had no problem running through mixtures of both kinds of files for hours on end. In fact, I've never had an issue.

 

If you have the CPU power to do so, try and up-sample to DSD128 (minimum) and see/hear if you like it better (or not).

 

https://positive-feedback.com/audio-discourse/raising-the-sample-rate-of-dsd-is-there-a-sweet-spot/

[asdf1000]

11 minutes ago, left channel said:

It also did very well in John Atkinson's measurements

 

[asdf1000]

Congrats to John Westlake.

 

And thanks to @Miska for telling us much of the same (and sharing measurements) some months ago.

 

Another snippet (the last one I'll share).

 

[asdf1000]

2 hours ago, left channel said:

It's sad that the article doesn't mention John Westlake at all, but as Pro-Ject no longer longer has a relationship with him they probably very studiously avoided any such discussion, focusing instead on their company founder and history, and on the product.

 

Do you remember John saying he was working on a version of the S2 DAC with network input?

 

Everything else much the same plus an OEM RPi board (not the usual RPi3 board we can buy)

 

Did that happen or fizzle or still happening, somewhere outside of ProJect?

[asdf1000]

2 minutes ago, left channel said:

His independent MDAC2 project is alive and well, with tons of discussion on pinkfishmedia.

 

I will head there for all nitty gritty details... but can you give a short summary of what this is? Key features?

 

Is that essentially a Pro-Ject S2 DAC with network input? Or something different?
 

[asdf1000]

1 hour ago, Display said:

HQPlayer... ???    Is it fair to promote here your expensive app

 

He was asked a question and simply answered the question he was asked..

 

[asdf1000]

1 hour ago, Miska said:

Also note that grounds of the two are connected.

 

For critical listening, I just power S2 DAC and UpBoard Gateway with a single 5Vdc USB powerbank.

 

Even though sharing same powerbank for 2 inputs of S2 DAC means sharing some noise, the mains ground loop (and mains RF) is killed.

 

[asdf1000]

56 minutes ago, matthias said:

 

Looking for a similar solution.......

Do you have a recommendation for a powerbank?

Thanks

 

Matt

 

I use this Mophie:

 

http://www.mophie.com/shop/universal-batteries/powerstation-XXL

 

[asdf1000]

5 hours ago, Miska said:

 

Batteries are not automatically better because they end up having switching regulator between the battery and DC output. And that's pretty much like having SMPS...

 

 

But much better than SMPS (or linear PSU) as they are 100% de-coupled from mains power issues (ground / leakage current loops and associated mains RF).

 

This can sometimes (depending on system) be much bigger issue than voltage regulation (which gets sorted inside the DAC eventually).

 

I know SMPS issues don't show on S2D measurements shown so far, but the sound seems smoother running on USB powerbank than SMPS to my ears... Re-connecting SMPS makes things sound a little brighter (again, subjectively).

 

I've found this with many 5Vdc powered DACs, not just S2D.

 

Even Chord Qutest - Rob Watts like powerbanks for the same reasons:

 

https://www.head-fi.org/threads/chord-electronics-qutest-dac-official-thread.869417/page-65#post-14097431

 

https://www.head-fi.org/threads/chord-electronics-qutest-dac-official-thread.869417/page-11#post-13970690

 

Ideally yes, ultra low noise linear regulated battery power would be best but you may already get some immediate benefit by de-coupling from AC power, even with USB powerbank...

[asdf1000]

Hi @Miska , i see you're at the Munich Show.

Do you know what this new DAC is about? Is it there at the show?

 

[asdf1000]

Seen it here:

 

https://www.soundandvision.com/content/pro-ject-audio-systems-thinks-beyond-box

 

[asdf1000]

On 4/24/2019 at 5:31 PM, Miska said:

The analog section chip in S2D uses built-in charge pump to create needed additional negative voltage rail, which is also kind of switching regulator

 

[asdf1000]

9 hours ago, Jumpwire said:

The problem is NOT fixed in 2.12 Firmware update.

 

Correct but you won't see the problem if you have your software perform the 1st unfold. In this mode, you'll see 'MQB' shown on the DAC's display.

 

The bug is only there when the DAC does the full MQA decode. What software are you using?

 

[asdf1000]

7 hours ago, left channel said:

This DAC is still known to be more sensitive than most to imperfections in an MQA signal, and for not falling back smoothly to an undecoded format when that happens.

 

I haven’t seen any reports of people having issues with the DAC in “MQB” mode... ie software does the 1st unfold and the DAC does “the rest” (rendering).

 

One of the software companies that offer the 1st unfold/decode mentioned this solution to me... the bug only shows up when the DAC has to do the full monty.