Fashionable Watches

SOtM sCLK OCX10 clock for sMS 200Ultra

SOtM sCLK OCX10 clock for sMS 200Ultra

Two years ago I reviewed the SOtM sMS-200
network bridge and was very enthusiastic. A year later I reviewed the sMS-200 Ultra
and was even more enthusiastic. A month after that I reviewed the NEO version
of it and this time the sound quality was improved slightly further. Then SOtM asked me to review this version
driven by an external clock unit, costing $ 3500. I was rather curious but had limited myself
to devices up to € 2000. Nevertheless, after a year, curiosity got
the better of me. And perhaps that was a mistake, a big mistake….. The sCLK-OCX10 comes in the same housing as
the sMS-200Ultra and the matching power supply, the sPS500. Since the sCLK-OCX10 is an optional clock
generator for the sMS-200Ultra and Ultra NEO, I suggest your also watch the reviews of these
devices. Technically there is a small difference between
the sMS-200 Ultra and the sMS-200 Ultra NEO, functionally they are equal. Another thing: I will refer to the sCLK-OCX10
as ‘Clock Generator’ to prevent tongue injury. For the same reason I will use ‘Network
Bridge’ for the sMS-200Ultra. When I say Network Bridge, I mean both the
normal Ultra and the NEO version. In both cases you do need to select the Master
Clock option on ordering. This will add a BNC connector to the rear
of the unit to connect the Clock Generator to. When ordering it is also clever to go for
the 12 volt version so you can use one power supply to power both units over a Y cable
– the Clock Generator is only available in a 12 volts DC version. The network bridge is connected to the router
over a network cable. This way it is connected to the internet and
other devices in the network, like a computer and a NAS. The USB output of the Network Bridge is connected
over a USB cable to the DAC in your stereo setup. Unless you have an amplifier with integrated
DAC, in which case it can be connected directly to the amp, provided it has a USB2 Audio Class
2 input. Almost all equipment with USB inputs younger
than 5 years will fulfil this requirement. As drawn here, this it the normal way to use
the Network Bridge. You only need player software on the computer
that can drive the Network Bridge. Roon, that I use, does that but any DLNA server
program can be used too and even Logitech Media Server – LMS for short – is supported
so that the Network Bridge can be used as high quality Squeezebox. The Network Bridge can also function as a
music server. It has a Music Player Deamon, LMS andMinimServer
aboard, meaning that you can use the Network Bridge as a streamer by itself. Time to connect the Clock Generator. That’s just a matter of connecting a 50
Ω BNC cable between the Clock Generator and the Network Bridge. As soon as the Network Bridge receives the
10 GHz clock signal, it will lock on that. The Network Bridge and the Clock Generator
use identical housings as does the matching power supply. They all measure 106 by 245 by 48 mm. The Network Bridge and the Clock Generator
weigh 1.5 kilos, the power supply 2 kilos. They all have this green power indicator that
doubles as standby switch on the Network Bridge and the Power Supply but not on the Clock
Generator. And rightly so, clock generators can best
be left switched on. As said, to use the Clock Generator you do
need a special version of the Network Bridge. This is the standard version, which has no
connector to link the Clock Generator to. The special version does have this BNC connector
and costs $ 200 more. Since we are here, let’s see what the other
connectors do. On the right the network socket, then a reset
button, two USB connectors for storage media if you use it as server, the power input,
the specially optimised USB audio output and the Micro SD card that holds the operating
system. Looking at the rear of the Clock Generator
we see the power input and four BNC connectors that all output the 10 GHz clock signal. You just connect one of these BNC’s over
a 50 Ω BNC cable to the clock input on the Network Bridge. From a technical perspective the SOtM approach
differs from how clock signals usually are done: they use a sine wave signal in stead
of a square wave. According to SOtM a lower noise clock signal
can be achieved this way. Something I can imagine since a sine wave
is a pure one, while a square wave is a sine wave with – theoretically – an unlimited number
of harmonics. Anyway, due to this approach other clock generators
should not be used with the SOtM Network Bridge. You have asked many times for a description
of my setups. Well, here roughly my setup 1. The Network Bridge is connected to the SOtM
network switch. This is connected over glass fibre to a Zyxel
switch. To that the Roon Rock NUC and the NAS are
connected over CAT6 patch cables. My router is connected to the SOtM switch
to provide internet access. The Clock Generator is connected to the Network
Bridge, both are powered by the SOtM power supply over a Y cable. The USB audio output of the Network Bridge
is connected to the USB input of the MiniDSP SHD that I use for room correction. The connection to the Mytek Brooklyn Bridge
is over SPDIF and the analog outputs are sent to the Audio Note Soro SE that is heavily
tweaked by Peter van Willenswaard of Audiomagic. The speakers are Audio Physic Scoprios. Cables are by AudioQuest, Crystal Cable and
SOtM. Now, here is where I encounter my first problem. How the Flac can I explain to you my listening
experience with this Clock Generator? I have been tripping and flipping in my review
of the Network Bridge without the Clock Generator. Adding the Clock Generator gave me another
euphoria. The sound is even less stressed, the stereo
image is now so deep and wide that I’m glad my neighbours are on holiday. For often instruments are halfway their living. The lows are extremely controlled and textured
while the highs are refined to the extreme. Even more impressive are transients that are
so well-timed, fast and real. They are probably the reason for the focussing
of instruments within that big stereo image. While listening I suddenly missed the magic
the Clock Generator brought, while I had not switched it off. It appeared that the Y-cable for powering
had a loose contact. It was a sunny day and then the Green power
indicators just light up by the sunlight so I could not have seen the defect, only hear. This way the sound improvement was 100% certified
by this experience, at least for me. Just to see the influence of the SOtM dCBL-BNC
cable that was sent to me with the Clock Generator, I replaced it with an off the shelf 50 Ω
BNC cable but that gave an immediate degradation of the sound quality. The SOtM cable sets you back € 700 but finding
a cheaper alternative won’t be easy since there are not much 50 Ω BNC cables around
that do 10GHz. And the SOtM cable does provide a very, very
good result. I am still worried I haven’t made clear
to you how big the sound improvement is adding the Clock Generator. Well, I did the best I could. If you’re interested in sound quality, you
must hear the total front-end reviewed here. Unless you lack the funds to buy it on the
spot. For you will be spoiled forever, your old
setup will no longer do. And that’s my second problem. But this is not about me, it’s all about
a fantastic three piece front end. At slightly over € 6.000 including VAT – the
European sales tax – it’s a lot of money and to be honest, the only comparison I have
is the Meridian 803.3 DAC/pre-amp. I already preferred my front end without Clock
Generator. Perhaps I might review comparable systems
in the future. I have said it before and I say it again,
developments in digital audio happen at a very high pace. At the introduction of the CD it was said
that we could have studio quality at home. I feel that after forty years this now is
really happening with equipment that can be saved for by normal people. That’s it for this week.. There will be another video next Friday, as
always at 5 PM central European time. If you don’t want to miss that, subscribe
to this channel or follow me on the social media so you’ll be warned when new videos
are out. If you liked this video, give it a thumbs
up. Many thanks to all that support this channel
financially, it keeps me independent and thus trustworthy. If you also feel like supporting my work,
the links are in the comments below this video on Youtube. I am Hans Beekhuyzen, thank you for watching
and see you in the next show or on And whatever you do, enjoy the music.

Reader Comments

  1. Great to see you astonished and emotional again Hans! I'm glad my sMS 200 Ultra Neo does not have that BNC on the back, else I might be tempted!

  2. Great to hear from You again!,!, Did miniDSP Studio “accepted”/ have Dirac V2.0? And one more question- is it possible to use HQPlayer with upsampling functionality in Your setup one? If Yes- will You try and come back with review? Thank You for answer in advance.

  3. I’m a little confused about how this works since USB connections asynchronous. Wouldn’t the clock in the DAC just undo the good work done by the clock in the bridge?

  4. Thanks for another great review. Would it make a further improvement if you were to connnect an external clock (also) to the Brooklyn? can the SOtM sCLK be connected to the Brooklyn?

  5. Thanks Hans for another gooood review. The sNH-10G have an optional clock input, can´t you test this too? It´s in your limit 😉

  6. Hallo Hans, stunning review my complements! Have you clocked your sNH10g as well on the system or do you use the basic sNH10g(as i do by the way) Then its easy to make a T powercable for your Mytek and sNH10g and feed them both;its plays on 9-12v without a problem..

  7. WARNING 12v without adjustment only works on the standard SOTM sNH10g; NOT on the clock version then you have to adjust thing at first inside!

  8. Thanks for updating us on your current System #1. Given that you are using the miniDSP SHD with Roon, I'm curious where you do the sample rate conversion? Do you let Roon do the work (along with DSD to PCM)? Or do you let the SHD have the honors? If so, do you use Roon's DSP functionality at all, or is it fully disabled?

  9. Hans, So from the review, I would just like to confirm that one could not use the Mutec Ref 10 master clock with the SOtM sms 200 ultra Neo or the SOtM network switch? If not, why not? It is a well regarded master clock. Thanks.

  10. Hans, one more try, this time a little clearer. The miniDSP SHD converts everything to 96KHz PCM for internal processing. Do you convert your digital stream ahead of time (in Roon or elsewhere)? Or do you allow the SHD to do it's own sample rate conversion? Thanks!

  11. Thanks for the review. Perhaps you could explain why SOtM has chosen to enable their sNH-10G switch to be enhanced with a BNC port for the Mutec Ref10, but NOT enabled the SMS-200ultra to do the same?

  12. Hi Hans, again a nice review of gear I am interested in.

    The SOTM set has been part of my possible upgrades for a while now, actually, since I heard of it at this channel. My Meridian Ultra DAC still sounds fantastic so I need evaluate this front end if it even will upgrade my set.

    What I am puzzled about is your remark about a sine wave clock vs a square wave clock.

    The improvement this clock makes must have its source in the reduction of jitter.

    Jitter is indeed very important and in the beginning of the digital age a fully misunderstood phenomenon. However, the easy explanation is that the right value at the wrong time is still wrong.

    Nevertheless, a sine wave that outperforms a square wave is strange. Sure, a perfect sine wave has no harmonics and this might or will influence the noise in the system. But reconstructing a clock from a sine wave is way harder than from a square wave. A sine wave has a slow rise time and therefore the receiving mechanism will have a harder time extracting a clock.

    I do trust your findings and what you hear and prefer is true …. For you …. And most likely for most of us, but it doesn’t make sense.

    The output is 2,85V 10MHz. the time for a quarter sine in this case is 25ns. If the decision circuit would have a threshold of 1/1000 of the amplitude, we would end up with a jitter of 25ps. A 20bit system needs approximately a maximum jitter of 8ps to become insignificant.

    Long story short: how much improvement in jitter performance is achieved with this clock? I would agree that a too fast clock will generate more noise, but using a sine …. I don’t know.

    I have a jitter analyzer designed long ago by Rémy Fourré at Ultra Analog especially for measuring clock jitter in audio. You connect its output to an Audio Precision and then make an FFT of the jitter frequency with a noise floor of 10fs ….. Maybe we should measure the difference and add proof to the subjective results.

  13. The review states that the sMS-200Ultra should not be used with other 10MHzclock generators that use square wave rather than SOtM's sine wave. Is there a technical justification for this comment? I (and many others) use the sMS200Ultra with a square wave generating Mutec REF10, this combination works very well. The sMS200Ultra locks to the clock signal, and sound quality improvements are clear.

Leave a Reply

Your email address will not be published. Required fields are marked *