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

[gahabana]

hi, i do not think so - but you can put it to 0dB and I guess it's fixed then unless you change it manually. It's all done in the chip anyhow, so 'fixed' vs 'variable' makes no difference ... 

[Panelhead]

5 hours ago, gahabana said:

my experience with "Pro-Ject Pre Box S2 digital DAC" ...all great except one major issue in my setup:

has mute on remote just like benchmark … what benchmark also did is ‘Dim’ which takes volume 20 or 30db down so if you get a phone call can still hear

Thanks !!!

  I have an idea on your sample rate "pop". Try turning volume down from unity while connected to a preamp. Then see if the pop is related to the reduced bit depth. 

  Also I am using an interface with the dim feature. It has a 24 bit chip. Tried using dim to reduce the attenuation level. The combination of "dim" enabled and volume pot turned up from around 12 to 3-4 o'clock does not sound as good as normal listening.

  I asked manufacturer how dim is implimented, dropping in volume control or switchable padding resistors somewhere. Does anyone know how dim function is usually done. Some are -12 dB, -18,  -20, and -24 dB. I suspect it is like mute and turns on a switch to decrease output.

[franz159]

1 hour ago, gahabana said:

hi, i do not think so - but you can put it to 0dB and I guess it's fixed then unless you change it manually. It's all done in the chip anyhow, so 'fixed' vs 'variable' makes no difference ... 

Which is indeed what I understand reading the user manual, where 0db attenuation means unity gain:

 

Volume Adjust the volume to the desired level from -80dB to 0dB, using the knob on the right side of the front panel. Volume settings are stored separately for headphone output and RCA output.

 

 

[gahabana]

1 minute ago, franz159 said:

Which is what the user manual says...

 

Volume Adjust the volume to the desired level from -80dB to 0dB, using the knob on the right side of the front panel. Volume settings are stored separately for headphone output and RCA output.

@Franz159 - spot on - that is how it works. One could have RCA's set at 0dB and headphones from 0 to -80dB and unless one is changing volume when headphones are not plugged in - it will always stay at 0db

 

[left channel]

Thank you for the review! I just ordered one from an eBay seller in Germany. It will take two weeks to get here. 

The same seller has a few more units available, in black and silver.

 

 

[gahabana]

18 minutes ago, left channel said:

Thank you for the review! I just ordered one from an eBay seller in Germany. It will take two weeks to get here. 

The same seller has a few more units available, in black and silver.

 

 

hi, 

several online stores have it (and some even authorised Pro-Ject partners/resellers/dealers)... same price (345 EUR) ... i ordered mine from hifinesse.com (also in germany as your ebay seller).

[gahabana]

1 hour ago, Panelhead said:

  I have an idea on your sample rate "pop". Try turning volume down from unity while connected to a preamp. Then see if the pop is related to the reduced bit depth. 

  Also I am using an interface with the dim feature. It has a 24 bit chip. Tried using dim to reduce the attenuation level. The combination of "dim" enabled and volume pot turned up from around 12 to 3-4 o'clock does not sound as good as normal listening.

  I asked manufacturer how dim is implimented, dropping in volume control or switchable padding resistors somewhere. Does anyone know how dim function is usually done. Some are -12 dB, -18,  -20, and -24 dB. I suspect it is like mute and turns on a switch to decrease output.

hi @Panelhead , on another thread (@ pinkfishmedia.com ) John Westlake who i understand is one of the designers of the S2 confimed that click is heard only when master clock changes (e.g. between 44.1/88.2/176.4/352.8 and 48/96/192/384khz) ... if it changes from 44.1 to DSF or 176.4 or 88.2 no clicks. same between 48/96 and 192 ... so nothing to do with bit depth but something else related to what happens when master clock changes (i guess they are at MHz range - 2 main clocks and all of the above is constructed by dividing master clock to get to target frequency)... he said he would look at it @ their lab ... maybe it's just my unit being weird. not sure yet.

[franz159]

The strange part is those pos and clicks being heard only when used as a pre-amp and not as a line source connected to another pre.

 

If the clicks are caused by  a "main frequency clock change", they should be heard irrespective of what happens downstream (another pre or a power amp).

 

8 hours ago, gahabana said:

......
I have no clue why i did not hear those clicks/pops when S2 was connected to Benchmark DAC2 which acted as pre-amplifier.
.....

[gahabana]

1 hour ago, franz159 said:

The strange part is those pos and clicks being heard only when used as a pre-amp and not as a line source connected to another pre.

 

If the clicks are caused by  a "main frequency clock change", they should be heard irrespective of what happens downstream (another pre or a power amp).

 

Franz, i hear pops either way. take a look at: http://www.pinkfishmedia.net/forum/showthread.php?p=3209587 discussion. JohnWestlake said they would look at it. have posted a recording of the pops. Reason why i heard none or very few when i had it previously connected to Benchmark DAC which acted as a pre is cause during that period i mainly listened to Roon upsampling all content to either 768kHz or to DSD256/512.... when no change in master clock - no pops or clicks whatsoever.

 

[franz159]

13 minutes ago, gahabana said:

Franz, i hear pops either way. take a look at: http://www.pinkfishmedia.net/forum/showthread.php?p=3209587 discussion. JohnWestlake said they would look at it. have posted a recording of the pops. Reason why i heard none or very few when i had it previously connected to Benchmark DAC which acted as a pre is cause during that period i mainly listened to Roon upsampling all content to either 768kHz or to DSD256/512.... when no change in master clock - no pops or clicks whatsoever.

 

Thanks for clarifying, this makes much more sense!

[arcman]

2 hours ago, left channel said:

Thank you for the review! I just ordered one from an eBay seller in Germany. It will take two weeks to get here. 

The same seller has a few more units available, in black and silver.

 

 

So you would need to add a us power cord?

[gahabana]

1 minute ago, arcman said:

So you would need to add a us power cord?

no power cords needed. it is powered via USB OR with the unit you get small smps power supply with microusb out that can power the  S2 DAC. It comes with EU, UK and US (three diferent ends) so will work more or less anywhere in the world ...

[arcman]

I just ordered mine from Analog Seduction in UK

[arcman]

Im going to sell my current peachtree nova pre and use the Pro-ject as a preamp until my Primaluna Prolog pre comes in. 

[Audio_ELF]

12 hours ago, gahabana said:

However, last step was to try S2 directly powering poweramp (Bryston SST2). All of the above still holds true however, there might be a problem for me to use it in that way unless you guys have some idea:
Issue: when sample rate changes between the tracks very often i hear a farily loud click/pop between the tracks. 

I have no clue why i did not hear those clicks/pops when S2 was connected to Benchmark DAC2 which acted as pre-amplifier.

I can offer you a theory as to why the pops/clicks but no real solution.

 

I would suggest the pops/clicks occur whether direct or via a pre-amp.  However if you are going via a preamp they are attenuated.

 

The pops are occurring at the output of the DAC so after the digital volume control.

[left channel]

9 hours ago, arcman said:

So you would need to add a us power cord?

 

9 hours ago, gahabana said:

no power cords needed. it is powered via USB OR with the unit you get small smps power supply with microusb out that can power the  S2 DAC. It comes with EU, UK and US (three diferent ends) so will work more or less anywhere in the world ...

 

That's correct, no power cord needed for USB. And in fact, reviewing the manual I see the "wall wart" is only for coaxial and optical connections, and not recommended for USB. Note the bit I've underlined below:

Mains power connection
The unit offers 2 possibilities:
1. USB input is not used: Connect the low voltage plug from the power supply to the micro-USB socket
Power 5V DC before connecting the power supply to the mains.
2. USB input is in use: Unit can be powered directly from computer via USB input. In this case is highly
recommended to disconnect Power 5V DC cable from the unit - power disturbances from two power supplies
could affect sound performance.

 

The unit has some interesting USB filtering built in, and I look forward to testing it with and without my USB REGEN inline.

[rickca]

I'd really like to see listening impressions of Pre Box S2 Digital vs iFi micro iDSD.

[arcman]

I'll actually be curious to a/b MQA and NON dsd high rez between the Bluesound Node2 and the Pro-Ject Dac. The Bluesound barely sounds better than my Peachtree Nova-pre (regualr hi rez). I find it interesting that the above reviewer heard no major sonic difference between the Benchmark and the Pro-ject.

[left channel]

Shipping update:
● Sunday 9/24, order placed
● Monday 9/25, shipped from Germany via DHL
● Friday 9/29, arrived in USA, delivered to USPS
● Saturday 9/30 out for delivery

That's less than half the posted shipping time estimate, probably because I live near DHL and USPS hubs. They will probably want a signature for this. Luckily today is a Saturday.

[franz159]

32 minutes ago, left channel said:

Shipping update:
● Sunday 9/24, order placed
● Monday 9/25, shipped from Germany via DHL
● Friday 9/29, arrived in USA, delivered to USPS
● Saturday 9/30 out for delivery

That's less than half the posted shipping time estimate, probably because I live near DHL and USPS hubs. They will probably want a signature for this. Luckily today is a Saturday.

...you are making all of us curious... looking forward to your findings

[left channel]

Received!

First of all, it's very small:

I'll be comparing it to the Schiit Audio Modi 2U & Magni 2U shown here.

[left channel]

I'm getting the same "pop" sound reported by @gahabana, apparently when the master clock changes. So not with every sample rate change, but about 2/3 of them, and every time it switches in and out of MQA. When the sample rate rises, the "pop" is heard on the left speaker. When the sample rate falls, it's always or usually on the right.

 

Also, the unit does not correctly sense and display sample rates from Qobuz. It does that OK with Tidal or MusicBee. I don't know if anyone has reported this yet. I see in the pinkfishmedia thread John Westlake promised to reduce the "pop" with a firmware update in a week or two. He said the fix would be "basically increasing the time before the DAC comes out of Mute after sample rate change." I hope that doesn't clip any music. 

This is clearly still a "version 1.0 product", even if the firmware version is 2.10. That's OK, that's what happens when you're an early adopter.

[left channel]

Setup was quite easy. A Windows driver is included on a CD for USB operation. No driver is required for Macs. When you run setup.exe in Windows it will ask you to plug in the unit, if you haven't done so already. I connected the Box via USB cable (the instructions advise a direct connection, no hub), and also connected the RCA outputs to my active speakers, then let the installer run.

After that the Pre Box was immediately ready, no PC reboot required. I selected USB with the Input buttons, and was immediately rewarded with the sounds of the internet radio stream I'd been playing. Plugging in my headphones, I was happy to see the Box will remember separate volume levels for the headphone tand preamp outputs.

As you can see from my photo, the unit is quite compact. It is a bit deeper than the Schiit Magni but only about 2/3 as wide, and runs 1/3 as hot. After some quick clicking around to ensure it will detect the resolutions and formats of different streams and files — which led to the popping sounds described in my previous post — I've been just letting the unit stream some music and have a good burn-in for awhile.

In fact, when run from USB the Pre Box will never turn completely off until the PC turns off, or until you unplug it from USB. When the PC is asleep, part of the display goes away and the USB icon turns red, but the big white volume numbers remain lit (and the nonexistent volume can still be adjusted via the knob or remote). By pressing in the volume knob or pressing the remote's "Mute" button, you can mute the unit to replace those numbers with a red muting icon, but it's still on.

More soon.

[arcman]

I wonder where one would download the firmware

[left channel]

The firmware update will probably be announced on the pinkfishmedia forum @gahabana is on, and a link will likely appear on the product web page. We'll keep an eye out for it.