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Pro-Ject Pre Box S2 digital DAC

MagnusH said:
Funny thing is, you don't get that glitch on that tune with the Explorer2 DAC, so it cant be a source problem only (unless Explorer2 did some workaround for it).

Btw, here is the Roon thread about the S2 dac, this problem is talked about at the end: https://community.roonlabs.com/t/pro-ject-pre-box-s2-digital/29726/130
Click to expand...

I'd really NOT read too much into that - its possible the time constance on the MQA detect is different between units....

Its simple - play the file via foobar and see if the dropouts can be repeated... If the drop-outs are repeated then this is a good step forward because Roon has been removed from the equation.
 
Interesting. According to that thread the same thing happens with the Mytek Brooklyn, with Roon or the Tidal app. Tidal does worse to us sometimes, especially in the Windows app: completely freezes the stream in-between tracks and sometimes during tracks. But this may be something completely different.
 
I've contacted MQA today to see if they can shed anymore light on the issue - I should hear back by Friday...
 
Apparently my interactions with Pro-Ject support are bearing further fruit. I just found this at the bottom of the product web page FAQ section, and hope to see the same information reflected in the manual and data sheet:

Q: Does the device support MQA over the coaxial or optical input?

A: No, in order to enable MQA playback via S/PDIF a hardware change would be necessary, this would cause the price to go much higher. MQA hardware decoding is only possible via the asynchronuous USB input of Pre Box S2 Digital.

In my next exchange I will also suggest that the manual's foobar setup be updated. First, this is not just for DSD: the ASIO component is also necessary to play MQA files. Second, the DSD setup is outdated and does not reflect recent versions of foobar.

That may be why I can play DSD128 files OK, but DSD256 files are distorted. At least I hope that's all it is, and that I can figure this out with some time and patience.
 
Nice work left channel....you handle Pro-Ject and I (try) to handle John :)

For DSD256, try to increase buffer in USB control panel, I have mine to "Relaxed" and "8192" samples, and DSD256 works.
 
Well Magnus, clearly they checked with John too, and were repeating part of that conversation without a filter. I would never use the words "asynchronous USB input" in a marketing document. :)

And thank you! That fixed my DSD256. Any setting above "Safe" works, as long as the ASIO buffer size is at maximum.

The manual doesn't reference the control panel at all. Someone needs to go through this step-by-step, taking new screen shots.
 
The default values should be set so that all supported format works. The slight audio-lag a high buffer value produce won't matter for normal listeners.
 
MagnusH said:
The default values should be set so that all supported format works. The slight audio-lag a high buffer value produce won't matter for normal listeners.
Click to expand...

Agreed. And the manual should tell us not to lower those settings when the control panel appears during DSD setup. I will suggest that. Anything else?
 
Is there some place where I can download the firmware solving the Click problem?
I have this issue using Tidal App on Windows 10.

Thanks in advance.
 
@seaiz I just responded to your PM with a link to my Dropbox folder containing the firmware update, no login required. Please let us know how your unit sounds after updating.
 
I've sent Pro-Ject suggested changes to the foobar setup instructions for DSD and MQA local file playback. I received a very nice reply thanking me and promising to update these soon.

Changes are needed to the instructions on the website ("Computer configuration for DSD playback") and in the user manual ("DSD Playback"). In addition to a general update to match the latest version of foobar2000, I've also suggested:

• the title should be "MQA and DSD Playback", because the first step (installation of the foo_out_asio component) is also required for local disk playback of MQA, and

• this product's control panel will appear during Preferences setup and should be explained, emphasizing the settings necessary to achieve all levels of DSD playback.
 
Here are some issues I know of:
- USB driver does not report the DACs correct capabilities to Roon (workaround: let Roon test the DACs capabilities).
- No native DSD available in Roon (and Windows?).
- Only 24 bit with WASAPI drivert (ASOI gives up to 32 bits).
- No DSD512 available, probably related to previous issues
- In Roon, its only possible to up-sample to 384 khz with WASAPI drivers
- MQA issues discussed earlier (occasional drop-back to PCM and stutter at beginning during transition to MQA).

Some of these might be problems with Roon, or problems due to Roon not knowing the capabilities of the DAC. None of the issues are serious for me, but might as well make Pro-Ject aware of them.
 
Thanks Magnus. Thoughts:
• I'm sure the WASAPI vs. ASIO issue will be of interest to John & Pro-Ject
• For the native DSD question, it would be helpful if you try foobar2000.
• The MQA thing seems to be Tidal garbling the track. Tidal has many problems.
• For a Roon-certified product, there seems to be a surprising number of features left for the two companies work out together.

There seem to be a number of European trade shows distracting Pro-Ject staff at the moment.
 
Thanks to @left channel for the new firmware. After the installation it seems to be almost perfect (no clicks when sample rate changes), except one small problem:
when I'm listenning some hires (192K MQA currently) album from Tidal continuously, there are small dropouts at the beggining of each song. First second it plays correctly, then it looses the sample rate, getting back to the default 48K, and in the next second it sets back the correct sample rate. And these changes are audible. It happens surprisingly after next song starts, instead of pause between the songs. Some latency or buffering delay problem?
 
Hi @seaiz, I saw your PM first but should repeat my answers here so everyone can benefit.

Re MQA streaming problems:

Those MQA dropouts are caused by Tidal. Sometimes you can get the same problem at the same point in a track every time, proving there is a problem in the copy of that track on the Tidal server. In other cases it's just a problem with Tidal's overall stream, and that is usually happening on Tidal's network (if your own local download speed and quality is OK). I believe that what it should do is show 48k at first, and then become fully unfolded to 88.2, 96, or 192k, sometimes so fast you may not see the 48k displayed on the DAC's screen. What it does instead is somehow lose the bit perfect quality it needs. This is not caused by your DAC.

Re MQA local playback (which you asked about in your PM):

To play local MQA files from foobar2000, you need to do the first step in the manual's instructions for DSD Playback setup: installation of the foo_out_asio component. Then MQA local file playback should work. While you're at it, you can continue the setup so you'll be ready for DSD files. The instructions are also missing this information about the settings for DSD256: in the Pro-Ject control panel, your Buffer Settings must be adjusted so that USB Streaming Mode is higher than "Safe" and the ASIO Buffer Size is at maximum.

OK?
 
I've received a question via PM about why a DragonFly may work smoothly while the Pro-Ject DAC experiences MQA dropouts. Before space limitations force me to delete everything from my inbox again, I'll repost my answer here.

The DragonFly is an MQA "renderer" that depends on Tidal's MQA 1x software decoding to work. Therefore it is receiving a different signal than the Pro-Ject DAC, which requires a bit perfect stream with MQA software decoding disabled.

When Tidal is unable to deliver a consistent bit perfect stream, due to either defects in the file on their server or because of problems in their delivery infrastructure, the 1x software decoding may still work but you will get dropouts on a full MQA 4x hardware decoder.
 
Hello everbody,

I just started with the Pro-Ject Pre Box S2 digital DAC and experienced the same problems as others described before. So, would anyone be so kind to give me a link to the new (beta) firmware.
Many thanks in advance.
 
hbit said:
Hello everbody,

I just started with the Pro-Ject Pre Box S2 digital DAC and experienced the same problems as others described before. So, would anyone be so kind to give me a link to the new (beta) firmware.
Many thanks in advance.
Click to expand...

PM sent.
 
Hello JohnW

"...Note the Pink / Silver organic capacitors..." Capacitors in the one I have bought are Blue/silver - are they approved, is this S2 OK?

Thank you, Regards;
Lonek
 
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