Pro-Ject Pre Box S2 Digital Impression Thread
Oct 17, 2017 at 9:53 AM Post #92 of 777
Has anyone compare this amazing DAC to Mojo or even read any comparison between those DACs'?

I did, as I stated in my too-long post on the previous page. And in quick succession since they were literally next to one another at a Jam last week-end. The setting was not ideal, and I could not listen to the same songs, but I had the same iems plugged into each, the well-balanced Nuforce HEM8. Honestly I was more impressed by the Pro-Ject, of which I had no expectations, than by the Mojo, whose fearsome reputation I was well aware of. The sense of ambient presence was better through the Pro-Ject, which also sounded a tad more energetic. In terms of decoding, as @Left Channel has stated the S2 is a wonderful toy full of possibilities, more so than the 2-year-old Mojo.

The S2 is small but still way bigger than the Mojo, however, so the Mojo will cover more use scenarios. That said, I also preferred RHA's very mobile Dacamp L1 to the Mojo. Obviously many will disagree, but looking at the recent price cut on the Dacamp L1 (down from Mojo price to $300, went for $255 last w-e on Amazon.com) a discount would seem in order over at Chord's. It is hard to consider the Mojo $200+ better unless you are an über-fan of its signature, want to drive very high-impedance phones yet need a super-small DAC/amp, or need the 2 headphone outs. Of course, since many argue that the Mojo isn't far from the Hugo (to which I would concur), that could pose a problem all along the line...
 
Oct 17, 2017 at 12:53 PM Post #93 of 777
I did, as I stated in my too-long post on the previous page. And in quick succession since they were literally next to one another at a Jam last week-end. The setting was not ideal, and I could not listen to the same songs, but I had the same iems plugged into each, the well-balanced Nuforce HEM8. Honestly I was more impressed by the Pro-Ject, of which I had no expectations, than by the Mojo, whose fearsome reputation I was well aware of. The sense of ambient presence was better through the Pro-Ject, which also sounded a tad more energetic. In terms of decoding, as @Left Channel has stated the S2 is a wonderful toy full of possibilities, more so than the 2-year-old Mojo.

The S2 is small but still way bigger than the Mojo, however, so the Mojo will cover more use scenarios. That said, I also preferred RHA's very mobile Dacamp L1 to the Mojo. Obviously many will disagree, but looking at the recent price cut on the Dacamp L1 (down from Mojo price to $300, went for $255 last w-e on Amazon.com) a discount would seem in order over at Chord's. It is hard to consider the Mojo $200+ better unless you are an über-fan of its signature, want to drive very high-impedance phones yet need a super-small DAC/amp, or need the 2 headphone outs. Of course, since many argue that the Mojo isn't far from the Hugo (to which I would concur), that could pose a problem all along the line...


Thanks for your feedback, Sorry I missed your previous post.
 
Oct 18, 2017 at 7:05 PM Post #96 of 777
The designer is working directly with ESS on the "pop" bug, but we can help by reporting this directly to Pro-Ject so that they will pay to get it fixed. This is their contact form: http://www.box-designs.com/main.php?info=kontakt&cat=default&lang=en

To reach Pro-Ject directly instead of a local distributor, I had to set my country to "Bermuda" on their contact form. But I then entered my true address, with state and country in the City field, and explained in my message along with a description of what I am hearing: a "pop" or "click" every time the sample rate changes between multiples of 44.1 and multiples of 48 kHz.

When listening to this product directly with headphones or active speakers, with nothing else in the chain, when the volume is loud the "pop" is loud too. It's very annoying after a while. I believe the only people who haven't heard this sound were listening at a show or doing a review using files within the same series, like 24/96 and 24/192. I am no longer using this product while waiting for a firmware update that will fix this.
 
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Oct 19, 2017 at 12:00 PM Post #97 of 777
I received a quick reply from Pro-Ject, saying "Hello! Thank you for your message. We're working on this issue. So far it seems like an ESS bug, hopefully it can be resolved by a firmware update."

More reports to Proj-Ject would be helpful. In addition to work on this bug, I see on another forum that they are working on DSD issues. I haven't seen reports of the channel imbalance mentioned by @ReignofError so perhaps that is something that was resolved by the full design early on.
 
Oct 24, 2017 at 3:12 AM Post #98 of 777
I received a quick reply from Pro-Ject, saying "Hello! Thank you for your message. We're working on this issue. So far it seems like an ESS bug, hopefully it can be resolved by a firmware update."

More reports to Proj-Ject would be helpful. In addition to work on this bug, I see on another forum that they are working on DSD issues. I haven't seen reports of the channel imbalance mentioned by @ReignofError so perhaps that is something that was resolved by the full design early on.

Thank you for feedback
 
Oct 26, 2017 at 4:39 PM Post #99 of 777
I've tested the beta firmware update, and the clock change "popping" sound appears to be fixed. At least three or four other end-users have tested it as well. There's been no further announcement, but I'm sure we'll see a final release soon. The update is loaded via the control panel. (The control panel was already placed in your Windows system tray when the driver was installed).
 
Oct 26, 2017 at 6:18 PM Post #100 of 777
I've tested the beta firmware update, and the clock change "popping" sound appears to be fixed. At least three or four other end-users have tested it as well. There's been no further announcement, but I'm sure we'll see a final release soon. The update is loaded via the control panel. (The control panel was already placed in your Windows system tray when the driver was installed).

Thanks for your feedback, that's a good news.
 
Oct 27, 2017 at 12:38 PM Post #101 of 777
[Edit: I've come back to this post three months later to update it so it remains useful.]

A note on external vs. USB power

The manual says we should use the included switching power supply for coaxial and optical input only, and when connected via USB we should not use the external supply.

In October 2017 the designer of this product, John Westlake, privately encouraged us to ignore that part of the manual and experiment with using external power adapters while connected via USB, for better sound quality. When an external adapter is connected, the device auto-switches from USB power to the adapter. All or most of us have found this improves the sound. This improvement has been greater than that provided by USB anti-jitter and/or USB power accessories.

In December 2017, he stated that we should do this only with a linear or battery power supply, to avoid possible noise from earth leakage currents. A number of users commented that they are seeing improvements and no problems using switching power supplies, including the stock adapter and the iFi iPower. However most of us are now using linear power supplies, ranging from cheap linear wall warts and phone battery packs to the UpTone LPS-1 and beyond.

In January 2018 Pro-Ject introduced two new products that meet those requirements: a battery PSU called the AccuBox S2 USB, and a linear supply called the PowerBox S2.
 

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Oct 28, 2017 at 6:37 AM Post #102 of 777
I was quite excited by this DAC/headphone amp but a closer look doused some of my initial enthusiasm. So I'm not surprised when the sound was described as not being high-end.

A SNR of 110 dB using the state of the art dual mono Sabre chips isn't particularly impressive nowadays, given than the lowly Chinese SMSL M8A using the DAC 9028q2m offers 117dB. Add to that the headphone amp doesn't seem powerful enough. Maybe they ought to forgo the MQA licensing fee and upgrade some internal components to make it a true giant killer...
 
Oct 28, 2017 at 1:29 PM Post #103 of 777
I can't comment on the sound, as I have not heard the unit ...yet. My thought was more to use it as a DAC. I think at some point I will try it. But we often fixate too much on numbers. at 110 DB SNR, noise should be inaudible. So what does more inaudible by achieving 117, or 120 DB SNR really get us? I think, nothing! I do agree though, MQA is not required. Unless streaming in a bandwidth limited scenario, I don't see its value.
MQA, for all of the hype, is still a lossy compression algorithm. If I am listening to locally stored music already in a High Res format, it really brings nothing to the party... except making Meridian a bunch of money.
 
Oct 28, 2017 at 7:10 PM Post #104 of 777
@chongky the original SMSL M8 had the same DSD channel reversal bug in its initial firmware release, and in general I think the M8/M8A line falls into the same class as the S2: they are only "Wow!" products in that they punch above their weight in the sub-$500 class.

The M8A should really only be compared to the Pro-Ject DAC Box S2+, not the Project Pre Box S2 Digital, as the M8A and the S2+ do not include a preamp, headphone amp, or MQA. Regardless, I'm first to declare all these products neither high-end nor high quality, but they certainly are surprising, and I'd be interested in seeing a report comparing the M8A and the S2 or S2+. I've seen both the M8A and the S2 described as very crisp and transparent, and I'm not at all certain I'd be able to hear a difference. Yes, the S2 headphone amp is less impressive than my Magni 2U, but it is competent, and anyway as I mentioned the M8A doesn't have one at all.

For me the S2 is primarily a low-cost drop-in MQA and DSD test box, as to my ears my Schiit stack remains champion of the weight class in all other ways. I think I can now safely say that MQA is something I can live without, but I did have to try it at full unfolding before making statements about it. Sometimes it improves the music, at least temporarily, and sometimes it makes the music worse. But I'm still listening...
 
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Oct 28, 2017 at 7:14 PM Post #105 of 777
I can't comment on the sound, as I have not heard the unit ...yet. My thought was more to use it as a DAC. I think at some point I will try it. But we often fixate too much on numbers. at 110 DB SNR, noise should be inaudible. So what does more inaudible by achieving 117, or 120 DB SNR really get us? I think, nothing! I do agree though, MQA is not required. Unless streaming in a bandwidth limited scenario, I don't see its value.
MQA, for all of the hype, is still a lossy compression algorithm. If I am listening to locally stored music already in a High Res format, it really brings nothing to the party... except making Meridian a bunch of money.

Sounds like the Pro-Ject DAC Box S2+ would be a better choice for you too! DAC only, no MQA.
 

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