Pro-Ject Pre Box S2 Digital

(Magnus) #766

I put mine on fast rolloff, because someone who seemed to know what he was talking about suggested that. There is also a bug with the optimal transient filter and MQA, so I would stay away from optimal transient.

(Geoff Mirelowitz) #767

I understood that bug was fixed with firmware 2.12. “Optimal transient” is the filter I use and I’m very happy with it.

(Sean) #768

Yep Jussi of HQPlayer says he did measurements and found that linear phase + fast rolloff and distortion compensation enabled, measured best - for when he was using the DAC for non-HQP related listening.

(John Hill) #769

Hi all, need some assistance. This is my second of these DAC’s - first one the power connector on the back broke off. It was replaced, but it took about a month. This was about 3 months ago.

Anyway…I might have a problem with the second one. All of a sudden, I can’t get any sound out of it. It appears like it is running fine with HQP and Roon just like before, but I am getting so sound. At first, I think it is my AVR, so I play around with my connections, etc, but no luck. I also notice that when I play a music file, the display says “384k”, no matter what I play. This is not correct, as I am upsampling to DSD 256.

I then unplug the USB and plug it back in, but when I play a file, it still says 384k, with no sound. So…I plug my headphones in the DAC and I can hear the music file, but just barely no matter how I adjust the volume. The music sounds like it is about 10 miles away. So, it does not appear as if the AVR is the problem. Any ideas on what is going on? HQP identifies the DAC as before and Roon shows it is playing. I am starting to think that the DAC has gone bad.


Onkyo AVR
Windows 10 PC
Digital S2 DAC

(Wim) #770

I’m sending my first one in for repair as the power connector broke off as well. I purchased a second unit to cover for the time needed for repair.

(Sean) #771

Hi John

Have you tried to simplify the chain and take HQP and the AVR out of the equation.

Can Windows itself play to the DAC with headphones via WASAPI, like YouTube?

Or Roon by itself direct to the DAC? Try both WASAP and ASIO modes on Windows.

(Adam Goodfellow) #772

Anyone heard anything more about John Westlake’s own firmware update for this?

Hoping that one day someone will fix the remaining bugs (MQA A drop outs, occasional crash).
Great sound, but nowhere near as reliable as a dragonfly red (also sabre 32 based) that I have never had any problems with.

(Sean) #773

Hi Adam, the MQA droupout issue disappeared for Roon users the day Roon could do the 1st unfold and the DAC set to Renderer mode (MQB mode). Have you tried that and still have issues?

Apart from that known MQA bug I haven’t seen myself or read about (on the 3 popular S2 DAC forums) any non-MQA related occasional crashes? Have you noticed anything that causes these crashes?

(Adam Goodfellow) #774

I didn’t say it was stopping me from using it with Roon, but it is still a paid for feature and we deserve a proper fix.

As for crashes, leave it on long enough - it will eventually crash.

(Sean) #775

Hi Adam, yes agreed. Have you emailed Pro-Ject Audio directly also? I would guess if enough customers email them directly (they don’t really have a forum presence), the MQA full decoding bug fix may come quicker. Although my understanding is it requires some work by MQA Ltd also, which may be holding up some things.

Noted - mine is left on 24/7 for months now and I haven’t seen this issue or seen anyone report it since the last firmware update (2.12). Probably another thing to report to Pro-Ject Audio so they can look into it?

(Adam Goodfellow) #776

As I understand it some kind of spat between John Westlake and pro-ject mean no fixes will be forthcoming from pro-ject - full stop.

This should not be our problem, but as always with commercial issues, it is never the people and companies involved who suffer. It is the paying end users.

(Sean) #777

If this is true, then there’s nothing anyone can do but wait and hope.

If there is an update, below is the thread to bookmark, follow and keep an eye on (John W posts here):

Your issue about crashing may be hardware related, not firmware - worth reporting to Pro-Ject Audio if I were you…

(Geoff Mirelowitz) #778

Apologies if this has been covered on this thread already but it’s hard to check a thread this long.

I am wondering if anyone has noticed a difference between setting the Pro-Ject up as both a Decoder and Renderer for MQA, and using it strictly as a Renderer, with Roon’s software doing the decoding?

Opinions or experiences would be appreciated.

(Wim) #779

I prefer to set it as a decoder only.
That way I do not have to change the settings between DSP enabled or disabled.
If I play an MQA file it plays MQA, if I play a non-MQA file it up-samples to DSD512, without changing any settings.

(SoulEye) #780

I use it sometimes like that too but most of the time I have it set “No MQA support” and upsample everything to DSD512.

(A Welshman, currently exiled in Hampshire) #782

Like this you mean?

(Magnus) #783

I have “No MQA Support”, since Roon takes care of first unfoild, and I replace second unfold with up-samplibg to DSD.

(A Welshman, currently exiled in Hampshire) #784

Yes understood and thank you

(Dale Clark) #785

I’ve never experienced any MQA dropouts at all. I love this dac and may buy a second one.

(Geoff Mirelowitz) #786

A question about an alternative power supply for this DAC.

I am considering this:

Naztech Volt 27,000mAh AC Power Station

Here are the specs:


  • Capacity: 27,000 mAh
  • 3 high-speed USB ports (USB-C + Quick Charge 3.0 + USB 3.0)
  • High-powered USB-C Port (5V/3A)
  • QC 3.0 Output: 5V/3A, 9V/2A, 12V/1.5A
  • USB Output: 5V/2.4A Max
  • Powerful AC Outlet (120V/85W)
  • Quick Charge 3.0 technology
  • Built-in LED flashlight
  • Temperature resistance
  • Input over-voltage protection
  • Over-current protection
  • Short-circuit protection
  • Power overload recovery
  • Battery cell protection
  • Automatic reset
  • Output current stabilizer
  • Overcharge protection
  • Dimensions: 7.4 x 4.8 x 1.2 in (18.9 x 12.2 x 3 cm)
  • Weight: 25.4 oz (720 g)

Any thoughts on whether this could work. Or – alternatively – is this the silliest idea you’ve ever heard of posted by someone who really doesn’t understand that much about alternative power supplies? (That could be me.)

In my own defense, there are many threads all over about this DAC and external power alternatives. It is my understanding the designer of the DAC (John Westlake) has suggested battery power is a good choice. But my knowledge is so limited I don’t really know if the device I posted above is the kind of thing he is talking about.

As always many thanks for any help anyone can offer.