Thanks Roy for his very insightful post and, of course, for sharing the fruits of his generous time and effort in what one can only describe as a wild audio journey. I tried to follow his experimental footsteps but took a simpler and slightly different path, which eliminates the number of boxes to give a clean and simple look that my wife would approve of.
First, I upgraded by SOtM sMS-1000SQ substantially with the following mods:
Added ethernet port via mini PCI-e (for a direct connection in case I would like to use it together with the sMS-200 ultra).
Installation of sCLK-EX board which clocks (i) the ethernet port on motherboard, (ii) the add-on mini PCI-e ethernet port, (iii) the system/CPU on motherboard and (iv) the built-in tX-USBexp card. I sacrificed the clock on the AES/EBU digital output as I do not see the use of it.
Installation of Intel X25E 64GB SSD as the OS drive (connected via an SOtM SATA filter that is in-built and which May claims to replace the SATA filter Roy is using. There is not enough space in the sMS-1000SQ chassis to fit the SATA filter II or III).
Installation of Eunhasu with direct ethernet connection capabilities. Needless to say, this setup is Roon ready.
Upgraded the capacitors.
Added the eABS-200 paper to prevent EMI.
All internal cables are upgraded to copper UP-OCC.
Added outboard master clock option.
Second, the SOtM sMS-1000SQ has or will have the following connections:
Currently, the sMS-1000SQ is powered by the stock power brick. I am waiting for a shipment of the Paul Hynes SR7MR4 DR to power this server.
sMS1000SQ is connected to the DAC through the tx-USBultra, which is in turn connected to my Chord Blu II. The USB connections are via one 0.2 cm Curious USB cable and one longer cheap USB cable (both of which I hope to upgrade to the SOtM filtered USB cable). My Uptone USPCB, unfortunately, does not fit anywhere in this setup given the lack of space.
sMS-1000SQ is connected to the SOtM modded router (see below) through two dCBL-CAT7 cables (one longer, one 50 cm only) with an iSO-CAT6 filter block in between.
Third, the router I am using is a ipTIME A8004NS-M, from a Korean brand which May kindly sourced for me. It's clock is fed by the sCLK-EX on my tX-USBultra. This router is powered by the SOtM sPS-500 at 12V 3.5A, and connects to my ethernet modem (which unfortunately I cannot mod given it is owned by my internet service provider) via one of the shorter SOtM 50 cm CAT7 cables. Since it's my only router at home, it needs to have wifi. Tidal streaming has not sounded better in my system.
Fourth, my tX-USBultra is also modded to include a master clock option, eABS-200 paper, and upgraded copper UP-OCC cables. It is currently powered by an Uptone LPS-1, but will soon be powered by the Paul Hynes SR7MR4 DR.
Lastly, the Chord Blu II is connected to the Chord DAVE via stock BNC cables (without ferrites), but I have ordered Wireworld Platinum Starlight 7 BNC 75 Ohm cables to replace these. I also have Nordost Vahalla II BNC cables to test and compare. The Chord DAVE is in turn connected to Omega Compact Alnico Monitors via High Fidelity Cables Ultimate Reference RCA cables. My entire rig will eventually be powered by High Fidelity Cables power cords.
I'm hardly competent in writing audio impressions but I believe I should say a word or two. I must say I am very happy with the result I get from all of this. Despite bits and bobs missing from my setup (such as upgraded BNC and USB cables, an NAS and the Paul Hynes SR7MR4 DR), my system has improved tremendously. The most significant piece of the puzzle is the Chord DAVE and Chord Blu II. But the upgrades which the server and router bring are absolutely undeniable. Taking the totality of the upgrades, what is evident is the lack of HF harshness, calmer presentation and smoothness of the sound, whilst retaining the impressive resolution delivered by the SOtM and Chord products directly to my speakers without loss of resolution through the use of an external amplifier.
Previously, with just the SOtM sMS-1000SQ (with the sCLK-EX but without other upgrades) the sound was manifestly on the bright and lean side of things. I believe this was the cause of some disappointment expressed by one or two reviewers of previous version of the SOtM sMS-1000SQ. With the upgrades in place, this is no longer the case: the sound is extremely effortless and relaxed and where the music calls for it, weighty and rich sounding. I should note however that the SOtM sMS-1000SQ standing alone does not sound nearly as good as when connected to the modded router and tX-USBultra, and I suspect that this has everything to do with clean power and super clocks. It appears, right now, the major component holding back on the sound would be my Omega speakers, which lacks the viscerality, bass impact and extension, soundstage and resolution of bigger or even more efficient speakers.
To put things in perspective, however, I must stress that the real game changer is the Chord Blu II. The DAVE, in comparison to not having the Blu II, sounds far more artificial and one can hear the jagged edges around voices and instruments. Sonic cues are more focused and less blurred. With the Blu II everything sounds more lifelike, properly positioned and voices no longer have any digital harshness or artificial jagged edges. Even Adele's rather raspy voice, which is very difficult to reproduce, manages to sound pleasant and alluring on this high resolution setup. This is not something which improvements on the server-side of things could reproduce.
Having read Roy's posts, these are the things I'm looking into and on which I hope to seek people's views:
SOtM's Master Clock device, which may even be better than Roy's Mutec REF10.
SOtM's tX-USBhubIN for connection to USB data storage drives (maybe the Lexar HR-1 compact flash hub and drives which Roy are using). May of SOtM tells me that NAS music storage is better than USB or internal storage, but Roy seems to take a different view.
Replacing the router with a lower powered one as Roy seems to find the lower powered Netgear router better sounding.
Stillpoints Ultra Minis under the chassis of the sMS-1000SQ, probably worth it if not because placing the sMS-1000SQ on my wooden floor generates excessive heat.
Upgrading all internal SOtM cabling to silver wires. I wonder if it will increase resolution. But so far I like the calm, effortless presentation of my system.
Upgrading clock on my ISO-Regen. I have an ISO-Regen lying around, mainly for my office system.