Unitiserve (US) + DC1

Are you hearing something that is amiss, or are you just looking to squeeze the last drops of performance out of the UnitiServe?  Have you brought home other sources that are better, or are you just looking for it to be the best it can be?

The UnitiServe functions both as a server and as a player, but as a player as you are using it I do not think it purports to be "reference quality."  The HDX is an upgrade from the UServe in that regard, so I understand. 

As you note, the Devialet cannot serve as a UPnP client.  Thus the UServe / Devialet is not a match made in heaven, as at it's heart the UServe is a UPnP server. 

Hi Keilic

I'm one of the few on here using a US driving SPDIF, and have made big gains optimising it.  The US performance is dictated in large by its PSU.  Btw, do you have a US HDD or SSD?

What kind of supply are you using?  The usual Israeli suspect really isn't linear, it has a 16v SMPS inside followed by a regulator.  Also it's SMPS has a floating output (rather than a grounded output like the supplied Naim PSU), and can introduce noise onto the output DC/SPDIF.  It does seems better on first install, improving resolution - but IMO still gets other things fundamentally wrong and leaves so much potential untapped.

I've 'enhanced' mine with significant added noise filtering, and my system lost its edge and gained resolution, naturalness & effortless dynamics - properly musical.  To me this has shown the massive gains possible.  From my experience I would recommend a true high- current low noise linear supply like a Hynes SR-5 as a 'properly engineered solution' and am now going this way myself.

Ferrites on each end of the DC1 also help.  I've used 'U25' ferrites and filed out the hole in the plastic case so it doesn't squeeze the DC1.  

Also use ferrites on the Ethernet cable into your US, and on the output of the Walmart feeding your switch.  Try and keep your wifi and broadband router well away from your audio switches.

Use the supplied Naim power cord for the 'serve with its in-line filter bump, it really is quite effective at reducing noise back into the mains and rest of your kit.  

The US provides far cleaner SPDIF with WAV files, less processing work = less noise. I converted my Hi-res library from FLAC, the difference was really compelling.

Properly set up, the US can be very good.....

Hope this helps.

You could try another cable instead of the DC1.     Im using the Nordost Heimdall 2 from US to Ndac.  I found the high frequency glare' that you mention and other artefacts not to my liking were attributable to the DC1.

However this might not be the way to go if your Devailet brings out its Ethernet option sooner rather than later. Although would be interesting to compare the US ability over all the options..

.....though if I was running a Devialet 800, I would be looking for something like the Aurender W20.  Has AES/EBU and USB digital outputs to play with ...

I have also used the Heimdall 2 like TobyJug and agree its softer, though I felt less dynamic and clear.  However in my experience cables were "lipstick on the pig" compared to the power supply influences.  Many orders of magnitude better, and much much cheaper, to remove the noise problem at source.

Buy a couple of large HY2 powdered iron ring cores (eg: 40x24x14.5mm) and take a few turns of your DC cable through each of them (try successive increments).  HY2 is a material optimised for lower frequencies up to 100s of KHz, where the primary switching noise is and often used for industrial lighting controllers. The HY2 ring cores will be epoxy enamelled. Even just bringing the DC cable in contact with the ring cores should be distinctly noticeable.

For a quick 'proof of concept' test, try taping the DC cable along a large steel bolt (eg: 150 to 200mm) or even a large steel tool!  You should hear an improvement.

I complement the HY2 ring-cores with a large ferrite for higher frequency (Mhz) noise. Don't use a split-ring, they loose their effectiveness at lower MHz frequencies.

For $30 the benefits can outweigh $1000s of conventional audiophile solutions.....

Hi, the SMPS noise will typically extend into 10's of MHz.. It will be harmonic related and as you say ferrite chokes are effective in reducing. The fundamental and lower harmonics will be typically dealt with by the bandwidth of the regulator itself and smoothing effect of reservoir capacitors, however when you exceed the regulators frequency response the RF chokes and low value decoupling capacitors start to kick in.

Common mode noise (wrt to capacitively coupled true ground) can be effectively dealt with by adding inductance to the coupled, or twisted PSU DC line as you say, but ground and the voltage line should be kept together in my view especially where higher value inductors are being used, otherwise I feel you will affect the line regulation wrt to current load.

However can you advise whether the US uses a galvanically isolated SPDIF out? That should reduce low frequency earth loops. (Mains frequency and lower harmonics)

Simon

Another option worth looking at the Melco N1A and using the USB output from that into the Devialet which i've heard is an excellent combination. 

Simon, the US coaxial output has shield connected to chassis/DC negative, and the supplied Naim SMPS has been selected to provide a grounded negative rail.  the Naim power cord filter only acts on phase/neutral and carefully bypasses earth

Consequently the SPDIF shield is nominally at ground potential with expectation that the receiver would be galvanically isolated.  Even with galvanic isolation high-frequency noise can couple through other mechanisms.

The popular Israeli PSU intended for the US has an internal SMPS with 2-wire AC feed.  The following regulator board doesn't have the normal electrolytic smoothing capacitors populated, appearing to rely mostly on the 4V drop across the 3-stage active regulator circuit.  As you point out, it's very easy for HF switching noise to still pass straight through.....

I've added ferrites and ceramic/metalized polyester caps on the SMPS output, and HY2 chokes on the DC output. Every step to clean up the DC into the 'Serve has been very noticible via the Naim DAC, significantly increasing the resolution, transparency and musicality.

Interesting info - thanks

S

Hi 40Below,

Thanks for that.  This is why I post here, for this type of gem reply.

Some of your tips are simple enough and I will try that.  However, can you explain the benefit of shielding the Ethernet cable?  Of course I use it only for connecting to wifi.  No music passes through Ethernet.  Also, I do have your suspected power supply from Israeli.  Have you actually used another with better results, or in the process of doing so?

As for the more technical tips, I will have to find non-work time to read and absorb.  Looks like some benefits there too.

Thanks

Keilic

I have also plugged in:

Power conditioner (Acoustic Revive RTP4 Ultimate)

New coaxial (Acoustic Revive DSIX)

Only been 1 day so these items may be running in.  I did power conditioner first with significant impact.  Digital cable 1 hour later, with subtle impact.  But first impressions:

Sound greater focus.  Like when you see an optometrist, and they swap the lens until your vision comes into focus. 

Glare gone.

Bass more pronounced.

More vibrant.

Will report more later if anything else interesting transpires.  But so far quite an amazing upgrade.  I am using the RPT4 on both the US and 2 x Devialet units.  So benefits more widely than just the US.

Hi Keilic

Thanks, I'm glad you found some of the suggestions useful.  A couple more learnings that may or may not be useful, depending on your setup and your level of optimisation (my wife might say "perfectionism").  Treat digital setup like you would a turntable, and things should be OK....

keep the US power supply a good distance (say 20-30cm) from other eqpt and any other cables; it does radiate noise that can take the edge off a revealing system.  Similarly keep good clearance in the 12v DC cable from running close to the US itself or other cables- it's carrying a few amps superimposed with digital noise..... (I loop a light rubber band around it to coax it into position and secure the band to wall with a blob of blu-tac)

route the DC1 so it keeps good distance clearance from other cables (not easy with its length), I aim for 10cm

keep the US itself clear from other signal eqpt. Naim recommend it's own support and 30cm distance for good reason. Like any audio eqpt it will benefit from some vibration-decoupling support.

i found a local switch and a short local Ethernet cable (Chord C-Stream works very well) preferable to a longer run of CAT6 To a remote switch. C-Stream has become a benchmark for quality/value in this region.

Keeping the Wifi router a good distance from the switch; I used two sections of cable coupled with a plastic extender to isolate the screens, and ferrites.  Wifi seems to infest everything I found it's effects can be heard downstream of a couple of switches and CAT6 links. Use lots of ferrites on the Ethernet, its only supporting a control function.

 I've recently moved to using a fibre Ethernet link to completely decouple the audio system and it's never sounded better, combined with my DIY power supply upgrade  - I haven't yet separated the benefits.

I am starting to trial an nd5 xs streamer for SPDIF into my DAC vs Unitiserve, but initial 'test run' just having it plugged in and on 5m of CAT6 to my upstream switch blunted off my current music, it will take some weekend time to do this properly.  I seem more likely to move on to a Paul Hynes Audio SR-5 supply for the Unitiserve to maximise its potential, this would also be usable with any future Mac Mini option. Hynes seems to set the benchmark in quality supplies for digital music systems.

Some very useful pointers there. Thank you !

Regarding the Paul Hynes PSU, it would suggest checking with him whether the PSU can supply the large current required to properly start the UnitiServe.

OK good, the transient capability will be more than sufficient. I'll email you with some off-forum questions.

Best regards,

Jan