[rb2013]

Creating a RAMDisk is not hard in Windows.  Creating a 'virtual' RAMdisk on an external USB drive to buffer music file playing in Foobar is.
https://www.tekrevue.com/tip/create-10-gbs-ram-disk-windows/
 
RAMdisks are designed to speed processing by creating a 'virtual' HDD/SDD in PC RAM.  Not the other way around - that is run RAM loaded programs in a USB 'virtual disk'.  At least not that I have been able to discover.  But I'm no computer engineer.  But it seems the transfer speeds may be just to slow to work effectively at the OS level.

 

[robi20064]

Actually I'm a computer engineer, and that's why I would like to figure out how could one have any SQ improvement by putting an USB (even SLC) into the StarTech versus playing from ramdisk. If the StarTech would act as a streamer and could pre-process the data (just like a microrendu) from the USB, than it could send it to your DAC directly, skipping the route back and forth to your PC. Reality is, it's not a streamer.

 

[rb2013]

  Actually I'm a computer engineer, and that's why I would like to figure out how could one have any SQ improvement by putting an USB (even SLC) into the StarTech versus playing from ramdisk. If the StarTech would act as a streamer and could pre-process the data (just like a microrendu) from the USB, than it could send it to your DAC directly, skipping the route back and forth to your PC. Reality is, it's not a streamer.

Great question!  And why does a SSD sound better then a HDD  - they do for me.  Funny I tried two SSD's to run my OS - one a lowly 120GB PNY 1311 and the other a blazing fast 240GB CS2211.  They sound virtually identical to me. But versus a WD 2TB Black - night and day.
 
Now a RAMdisk is playing from the PC MB RAM in a noisy EMI/RFI environment - maybe not optimal for music playback.  The moving of the music file storage conversion from steady sate to active data stream is now done in a 'clean' ultra low noise LPS powered environment.  The SSD reducing the power demands dramatically on the PC PS.
 
Didn't think the mR didn't need a PC for audio player playback?  But don't even start with DNLA/UpNP - they have huge issues of their own - see the posts on the first few pages - like this one:
 
More interesting quotes from this CA thread (I added the bolding):
 
http://www.computeraudiophile.com/f22-networking-networked-audio-and-streaming/ravenna-streamer-24708/#post433300
 
 
 
Quote:

 

09-15-2014, 02:07 PM

#33​

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Miska

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12

Originally Posted by tranz
But if all the user wants to do is serve audio files unaltered, unprocessed, without upsampling to the DAC, why would DLNA not suffice?






That's quite limited use case...

I didn't even get to dealing with digital room correction and multichannel setups yet.
 
Are there packets or bits getting lost without the user knowing?




For getting unaltered data to DAC, DLNA is not good either. First, to get anything
started it requires very delicate dancing between three devices. And it requires
processing from the renderer (decoding source content). It is not very good for
unprocessed either, because you don't know if and how the server is messing
with your data.

At the end, It is practically same as telling your web browser to play content from
a web server, like YouTube. Control Point is telling which content Renderer (you
web browser) should load from the Media Server (web server). If you need to
seek backwards, Renderer needs to disconnect from the server and issue a
new HTTP GET request, because you cannot go backwards in the stream. Since
the GET request is made with byte offset it is only whereabouts with any
compressed stream (like FLAC), because exact position cannot be calculated
on a variable bitrate.
 

I didn't like UPnP before, and after implementing UPnP/AV support to
HQPlayer I like it even less. It is also very prone to all kinds of network
issues which are hard to track down. For example I had two dumb gigabit
switches (non-managed) that didn't pass UPnP for some strange reason, but for
example NAA was working fine through those. I spent lot of time chasing down
why it didn't work and at the end, using Wireshark I discovered that the mDNS
packets sent to the switch didn't appear on any other port. It's a tech support
nightmare





​

 

[rb2013]

There have been many comments posted in various forums about the superiority of USB/microSD/PCIe ext SSD versus playing music files from a SSD or HDD inside the PC.  Now maybe running a SSD (with SLCp cache) on an external PCIe enclosure with it's own LPS could be as good or better then these simple USB sticks or microSD SLC cards in the REX - but that would entail a lot of addition cost.  If you already are using the Startech/ICRON for audio USB playback - the cost of $50-$60 to add a high capacity USB stick or low capacity mircoSD SLC is pretty minor.
 
I love Engineers - they need to have a scientific explanation for everything.   But they fail to realize that much cutting edge science was done on an empirical basis - only latter did the theories come to 'explain' it.  Like in Quantum Mechanics - it all started with  a 'simple' paper by Einstein on 'black body' radiation - leading to the idea of light quanta.  Or Rutherford's scattering experiments - leading to idea that atoms had components and a nucleus, or Young's double slit experiments pointing to a wave like nature to matter, etc..
 
By using our ears we are doing the same thing - empirical study - subject yes - but if many agree to these subject positives - that makes for validity.  Without the need for 'cause of action' to be completely understood.
 
http://jplay.eu/forum/index.php?/topic/1553-infinity-blade-hq-bug-head-emperor-worth-trying/page-170
 
http://www.computeraudiophile.com/f7-disk-storage-music-library-storage/does-solid-state-drive-sound-better-hard-disk-1650/index4.html

 

[mozes]

  There have been many comments posted in various forums about the superiority of USB/microSD/PCIe ext SSD versus playing music files from a SSD or HDD inside the PC.  Now maybe running a SSD (with SLCp cache) on an external PCIe enclosure with it's own LPS could be as good or better then these simple USB sticks or microSD SLC cards in the REX - but that would entail a lot of addition cost.  If you already are using the Startech/ICRON for audio USB playback - the cost of $50-$60 to add a high capacity USB stick or low capacity mircoSD SLC is pretty minor.
 
I love Engineers - they need to have a scientific explanation for everything.   But they fail to realize that much cutting edge science was done on an empirical basis - only latter did the theories come to 'explain' it.  Like in Quantum Mechanics - it all started with  a 'simple' paper by Einstein on 'black body' radiation - leading to the idea of light quanta.  Or Rutherford's scattering experiments - leading to idea that atoms had components and a nucleus, or Young's double slit experiments pointing to a wave like nature to matter, etc..
 
By using our ears we are doing the same thing - empirical study - subject yes - but if many agree to these subject positives - that makes for validity.  Without the need for 'cause of action' to be completely understood.
 
http://jplay.eu/forum/index.php?/topic/1553-infinity-blade-hq-bug-head-emperor-worth-trying/page-170
 
http://www.computeraudiophile.com/f7-disk-storage-music-library-storage/does-solid-state-drive-sound-better-hard-disk-1650/index4.html

Hi, what a great thread you are leading here, a lot of great information and can be overwhelming for someone not too technical like me. I like your idea of an external PCI enclosure with an SSD drive to play music. I have a laptop that I use for music and I would like to test this concept of yours. Kindly, can you share some links to parts needed to build this solution with a Win 10 laptop? Thanks

 

[robi20064]

From a scientific pov the SSD vs HDD difference at least can be explained. The HDD is based on a moving platter(s) and having an internal motor to make it spin, reading stored data on a "magnetic" way, while the SSD is basically "only" a set of memory chips. Even if you take out the speed differences from the equation there shall be still additional  EMI/RFI associated with HDDs.
 
Your PC might be still noisy for EMI/RFI, but the point is, no matter if the data (music) is stored on the USB attached to the StarTech or on the internal SSD in the PC or in RAMdisk, at the end it will be copied into your RAM in all 3 cases. The playback software simple cannot process is on any other way. In your StarTech example, it will open the files from the USB attached to the REX, allocate memory for data from your PC memory, read data from USB to the allocated PC memory, process it (depending on the playback application) and finally send it to your DAC through the StarTech again from the PC memory. In a case of a microrendu your PC acts only as a "controller" telling the rendu what to process. After that the rendu will open the file (most of the times from a LAN share / NAS using the network), read it into the rendu's internal memory, process it, and finally send it to the DAC which is directly attached to it. This way any EMI/RFI in your PC shall not affect the processing of data. The difference between options such as DLNA/Roon/HQP and others is about how data reaching the microrendu box.
 
Don't get me wrong, I'm not questioning what you "hear" with all these improvements in your chain, but I would still like to backup some of the "assumptions" with facts or science
 
I'm still heavily thinking of getting a StarTech/Icron for my setup, however - if I'm being honest to myself - I'm not sure I have good enough ears to notice the difference - even if there is going to be any.

 

[Mr Underhill]

Robi,
 
The system you have described, and the movement of the data, is a gross simplification and ignores numerous factors. Ultimately I think with much of what we are dealing with in our audio systems the best measuring system we have is our ears. If you find the differences small or unappreciable then you can just ignore them. Unfortunately  generally the only way to know is to try.
 
In a post I did a couple of days ago I reported that I had some audio engineers around to listen to my system, one they know well and have listened to before. Now these guys do have good ears. In one case I had ripped a 5.1 soundtrack from a DVD and converted it to PCM16, and they spotted it; and believe me it sounds very good. They were flabbergasted that the same file played from the StarTech sounded different from when it was played from my NAS - and I haven't added the LPSUs yet.
 
The complexities in this area are enormous, and although I have read a lot I do not pretend to really understand what is going on, although I can throw a lot of jargon around. I enjoyed this interview:
 
http://www.audiostream.com/content/ces-2017-conversation-juergen-reis-mbl-and-john-atkinson
 
Go to 13min.
 
M

 

[Superdad]

  From a scientific pov the SSD vs HDD difference at least can be explained. The HDD is based on a moving platter(s) and having an internal motor to make it spin, reading stored data on a "magnetic" way, while the SSD is basically "only" a set of memory chips. Even if you take out the speed differences from the equation there shall be still additional  EMI/RFI associated with HDDs.
 
Your PC might be still noisy for EMI/RFI, but the point is, no matter if the data (music) is stored on the USB attached to the StarTech or on the internal SSD in the PC or in RAMdisk, at the end it will be copied into your RAM in all 3 cases. The playback software simple cannot process is on any other way. In your StarTech example, it will open the files from the USB attached to the REX, allocate memory for data from your PC memory, read data from USB to the allocated PC memory, process it (depending on the playback application) and finally send it to your DAC through the StarTech again from the PC memory. In a case of a microrendu your PC acts only as a "controller" telling the rendu what to process. After that the rendu will open the file (most of the times from a LAN share / NAS using the network), read it into the rendu's internal memory, process it, and finally send it to the DAC which is directly attached to it. This way any EMI/RFI in your PC shall not affect the processing of data. The difference between options such as DLNA/Roon/HQP and others is about how data reaching the microrendu box.
 
Don't get me wrong, I'm not questioning what you "hear" with all these improvements in your chain, but I would still like to backup some of the "assumptions" with facts or science
 
I'm still heavily thinking of getting a StarTech/Icron for my setup, however - if I'm being honest to myself - I'm not sure I have good enough ears to notice the difference - even if there is going to be any.

Most of the differences between SSD vs. HD (or between an awful lot of any of the other stuff in computer audio playback) can be seen and explained by looking closely at the bursty patterns of current draw and the ground-plane noise modulation that comes from the device and goes into the power supplies of the rest of the system.  That's why such gains are made with separate supplies.
 
With regards to the route that data from a USB stick in the spare Starch/ICRON port takes:
Remember, even though that end of the extender is--with its other USB port--feeding the DAC, the data gets read from the stick, sent back over the Ethernet lines (direct or through a switch), to the local (LEX) end of the extender, then into the computer's USB port, through the OS, into RAM, then played by the player s/w, back though the audio drivers, back out the USB port, back into the Startech, back over Ethernet, through the switch, to the REX end Starch/ICRON box, and finally out its USB port to the DAC.  Whew...  The Starch/ICRON is not doing any rendering or shortening of the path. 
 
I'm not saying that what Rob is hearing in not real.  But I think the reasons for it may be different than what are assumed.

 

[Superdad]

  Robi,
 
The complexities in this area are enormous, and although I have read a lot I do not pretend to really understand what is going on, although I can throw a lot of jargon around. I enjoyed this interview:
 
http://www.audiostream.com/content/ces-2017-conversation-juergen-reis-mbl-and-john-atkinson
 
Go to 13min.
 
M

 
What Juergen of MBL is speaking of at minute 13--the "back doors of influence"--are AC "leakage loops," a term coined (I think) by my partner John Swenson, and are indeed a huge factor in every audio system, especially those with computers.  (I may get in trouble for saying so here, but on November 18th, 2016 Mr. Reis wrote to me and purchased one of our UltraCap LPS-1 units precisely because they block the path of leakage loops.)  
 
Isolating power and eliminating AC leakage (which rides on DC cables, on analog cables, on chassis--between all components that have power supplies) is among the last major frontiers for making big strides in SQ.  An awful lot of what is being heard and discussed--here, in other threads, and elsewhere--is primarily caused by current draw bursty patterns and AC leakage loops.
 
 
[Again, if the mods wish to censor the above, then please finally answer one of my many messages requesting information on sponsoring here at Head-Fi.  Your readership enjoys participation by and educational information from members-of-the-trade. And as seen on that other forum I call home, no one would ever label me a hype engine or marketeer.  40 years a music lover, audiophile, and yes, a hobbyist and manufacturer.]
 
Cheers,
 
--Alex C.

 

[rb2013]

  From a scientific pov the SSD vs HDD difference at least can be explained. The HDD is based on a moving platter(s) and having an internal motor to make it spin, reading stored data on a "magnetic" way, while the SSD is basically "only" a set of memory chips. Even if you take out the speed differences from the equation there shall be still additional  EMI/RFI associated with HDDs.
 
Your PC might be still noisy for EMI/RFI, but the point is, no matter if the data (music) is stored on the USB attached to the StarTech or on the internal SSD in the PC or in RAMdisk, at the end it will be copied into your RAM in all 3 cases. The playback software simple cannot process is on any other way. In your StarTech example, it will open the files from the USB attached to the REX, allocate memory for data from your PC memory, read data from USB to the allocated PC memory, process it (depending on the playback application) and finally send it to your DAC through the StarTech again from the PC memory. In a case of a microrendu your PC acts only as a "controller" telling the rendu what to process. After that the rendu will open the file (most of the times from a LAN share / NAS using the network), read it into the rendu's internal memory, process it, and finally send it to the DAC which is directly attached to it. This way any EMI/RFI in your PC shall not affect the processing of data. The difference between options such as DLNA/Roon/HQP and others is about how data reaching the microrendu box.
 
Don't get me wrong, I'm not questioning what you "hear" with all these improvements in your chain, but I would still like to backup some of the "assumptions" with facts or science
 
I'm still heavily thinking of getting a StarTech/Icron for my setup, however - if I'm being honest to myself - I'm not sure I have good enough ears to notice the difference - even if there is going to be any.

Doesn't the mR require a USB device to get to a pure DAC.  In other words there is one more step in that chain.  So you are still left with USB in between - and how does THAT part of the chain gets processed and transferred?
 
http://www.sonore.us/microRendu.html

 

HARDWARE FEATURES

1. External power input jack
2. RJ45 input connector
3. USB audio output connector

So you have vastly oversimplified the mR chain.
 
I want to state as clear as possible - I have no agenda to promote anything - nor am I recommending anyone buy or borrow anything.  I am simply conveying my subject listening results.  I do have a lot of experience in the past few years with DDC's and not much else changing in my system.
 
Now on to 'cause of action' theories and speculations - as to why I (and so far a few others) have experienced SQ improvements with the Startech.  First the use of the Startech for music file playback is a secondary use - the primary is galvanic isolation of the USB chain between PC and DDC/DAC.  I don't think there is much debate on this 'cause of action'.  Possibly a secondary benefit of the USB>IP then IP>USB packet translation is improved signal integrity.  Some speculation here.
 
Now on to it's secondary use as a external storage device.  I can easily hear differences in the high capacity PNY USB sticks and the SLC microSD card (by way of a USB 3.0 adapter).  Note the PNY USB sticks were much superior to a non-SLC microSD card.  OK something is going on here.
 
So here is my supposition:
 
The data in all solid state devices are stored in phyiscal memory called NAND flash memory.  So let's look at how NAND flash memory stores our music files in a solid state way.  That is permanent with out power.

NAND flash

NAND flash also uses floating-gate transistors

NAND flash uses tunnel injection for writing and tunnel release for erasing. NAND flash memory forms the core of the removable USB storage devices known as USB flash drives, as well as most memory card formats and solid-state drives available today.

Tunnel injection is a field electron emission effect; specifically a quantum process called Fowler–Nordheim tunneling, whereby charge carriersare injected to an electric conductor through a thin layer of an electric insulator.

It is used to program NAND flash memory. The process used for erasing is called tunnel release.

 
http://www.explainthatstuff.com/flashmemory.html
Quote:

 

How flash memory works—the simple explanation

Flash works using an entirely different kind of transistor that stays switched on (or switched off) even when the power is turned off. A normal transistor has three connections (wires that control it) called the source, drain, and gate. Think of a transistor as a pipe through which electricity can flow as though it's water. One end of the pipe (where the water flows in) is called the source—think of that as a tap or faucet. The other end of the pipe is called the drain—where the water drains out and flows away. In between the source and drain, blocking the pipe, there's a gate. When the gate is closed, the pipe is shut off, no electricity can flow and the transistor is off. In this state, the transistor stores a zero. When the gate is opened, electricity flows, the transistor is on, and it stores a one. But when the power is turned off, the transistor switches off too. When you switch the power back on, the transistor is still off, and since you can't know whether it was on or off before the power was removed, you can see why we say it "forgets" any information it stores.
A flash transistor is different because it has a second gate above the first one. When the gate opens, some electricity leaks up the first gate and stays there, in between the first gate and the second one, recording a number one. Even if the power is turned off, the electricity is still there between the two gates. That's how the transistor stores its information whether the power is on or off. The information can be erased by making the "trapped electricity" drain back down again.

How flash memory works—a more complex explanation

In this state, the transistor is switched off—and effectively storing a zero. How do we switch it on? Both the source and the drain regions are rich in electrons (because they're made of n-type silicon), but electrons cannot flow from source to drain because of the electron deficient, p-type material between them. But if we apply a positive voltage to the transistor's two contacts, called the bitline and the wordline, electrons get pulled in a rush from source to drain. A few also manage to wriggle through the oxide layer by a process called tunneling and get stuck on the floating gate:

 The presence of electrons on the floating gate is how a flash transistor stores a one. The electrons will stay there indefinitely, even when the positive voltages are removed and whether there is power supplied to the circuit or not. The electrons can be flushed out by putting a negative voltage on the wordline—which repels the electrons back the way they came, clearing the floating gate and making the transistor store a zero again.

 
 
OK now errors, possibly from PS noise or RFI/EMI noise can effect both the storage and the retrieval of this stored information.
 
Think of what physicists call 'Phase transitions'  for example ice.  At a certain temperature ice transitions from a solid state to a liquid state.  It doesn't happen gradually as the temperature rises from say 0 degrees F to 32 degrees.  No -  STAYS solid right up until the 'Phase transition'.  Now during this Phase transition - the ice crystal is unstable - heat it fast enough and it will explode! 
 
Once the ice is stably melted into water, it's in a liquid state and can move and used to do all kinds of things - like bathing, or cutting steel, etc.  Water can be directed in this movement by pipes and pumps.
 
OK now we have a solid state gate holding our music data - it must also be transitioned into a new state - a flow of electrons.  It's during this critical process of being 'read' that errors can occur.  In a cleaner, lower noise environment this is better performed.  The power needed to perform this 'read' process is cleaner as well. 
 
Another possible cause of action is the slower transfer speed of high speed USB vs SATA.  Allowing for a smoother loading and unloading into RAM for processing.

 

[rb2013]

 
Most of the differences between SSD vs. HD (or between an awful lot of any of the other stuff in computer audio playback) can be seen and explained by looking closely at the bursty patterns of current draw and the ground-plane noise modulation that comes from the device and goes into the power supplies of the rest of the system.  That's why such gains are made with separate supplies.
 
With regards to the route that data from a USB stick in the spare Starch/ICRON port takes:
Remember, even though that end of the extender is--with its other USB port--feeding the DAC, the data gets read from the stick, sent back over the Ethernet lines (direct or through a switch), to the local (LEX) end of the extender, then into the computer's USB port, through the OS, into RAM, then played by the player s/w, back though the audio drivers, back out the USB port, back into the Startech, back over Ethernet, through the switch, to the REX end Starch/ICRON box, and finally out its USB port to the DAC.  Whew...  The Starch/ICRON is not doing any rendering or shortening of the path. 
 
I'm not saying that what Rob is hearing in not real.  But I think the reasons for it may be different than what are assumed

I think moving the storage reading out of the PC as well as running the OS off a SSD has improved the SQ.

Interesting the SQ difference between a microSD SLC and high capacity USB stick in the REX.
 
I remember you recommending at one time an external LPS powered PCIe (or was it a Thunderbolt) SSD for music  storage I think?

 

[Mr Underhill]

   
What Juergen of MBL is speaking of at minute 13--the "back doors of influence"--are AC "leakage loops," a term coined (I think) by my partner John Swenson, and are indeed a huge factor in every audio system, especially those with computers.  (I may get in trouble for saying so here, but on November 18th, 2016 Mr. Reis wrote to me and purchased one of our UltraCap LPS-1 units precisely because they block the path of leakage loops.)  
 

Morning Alex,
 
I would say - partially, probably. Juergen mentions impedance, and that he can hear changes in different system configurations. I suspect he would mention a number of different theories that may explain the observed facts.
 
In my case when I have gradually repeated Rob's hard work I will probably buy a couple of battery packs and listen to the changes they bring, before buying an LPS1 and doing more work on leakage loops.
 
One of the largest changes I heard in my system was adding an isolating transformer between my Bel Canto 3.5vbs DAC and my EAR/Yoshino pre-map, why was it effective? Good question, possible theories include: DC offset blocking; Ground loop; Leakage loop; Poorly designed balanced outputs/inputs (my tongue is in my cheek when mentioning this but it was suggested by Roger, one of my audio engineering friends).
 
It is amazing to me how sensitive our systems are. Roger runs recording systems around the globe and he also heard the changes in my system but, as he would point out, the recordings are done using balanced audio circuits, CAT5 cables onto commercial SANs.
 
I would love to think that we could simply measure differences, but I am not convinced we know yet what we are trying to measure, and that these differences may be lost in the noise floor ....and yet audible.
 
I am grateful to Rob for sticking his head over the parapet.
 
Great hobby.
 
M

 

[Mr Underhill]

To correct some mis-information I posted above:
 
There were no Teradak x1/x2 on ebay, although a selection of new Teradak PSUs. I wrongly assumed that the unit was no longer available. I went onto the Teradak site and have since been in correspondence with Michael Li - new x1/x2 unit ordered.
 
M

 

[rb2013]

  To correct some mis-information I posted above:
 
There were no Teradak x1/x2 on ebay, although a selection of new Teradak PSUs. I wrongly assumed that the unit was no longer available. I went onto the Teradak site and have since been in correspondence with Michael Li - new x1/x2 unit ordered.
 
M

Great link and previous comments - good to hear the vertiable X!/X2 is still available.
 
I see they changed the caps from the gray colored panasonic FM's to these black caps with gold markings.  anybody know which these are?
http://www.ebay.com/itm/TeraDak-TeraLink-X1-X2-DC8-5V-1A-USB-DC5V-port-Linear-Power-Supply-/222387365233?hash=item33c751e571:g3cAAOSw-FZXkEMi
 

 
 
 
Here is the previous version with Panasonic FC 25v 1500uf caps (rated Impedance: 30mOhm, Ripple: 1.55A@120Hz, they do not show an ESR rating for these)

 
 
I replaced them with Nichicon HW's (With Nichicon HW  25V 1500uf - 10,000hr (105C), low impedance: 16mOhm, Ripple 1.56A@120Hz.)

 

As you can see the HW's have almost half the impedance of the previous stock FC's.  Other good choices could be the Pannie FM's with 15mOhm, and the Rubycon ZLG with 12mOhm.
 
http://www.digikey.com/product-detail/en/panasonic-electronic-components/EEU-FM1E152/P12380-ND/613741
 
Changing out these 8 caps should only be done by a Professional or very knowledgable DIYer.  The caps themselves are relatively cheap at around $1 each.

 

[Narayan23]

  I think moving the storage reading out of the PC as well as running the OS off a SSD has improved the SQ.

Interesting the SQ difference between a microSD SLC and high capacity USB stick in the REX.
 
I remember you recommending at one time an external LPS powered PCIe (or was it a Thunderbolt) SSD for music  storage I think?

Rob your comment had me thinking about one of these docking stations :
 
 http://www.ebay.com/itm/Satechi-Aluminum-USB-3-0-SATA-III-HDD-SSD-Docking-Station-with-2-Port-SD-10Q-/321953951935/?_ul=HN
 
I posted the above because of versatility (HDD/SSD, USB 3.0, SD/SDHC/SDXC reader) those wanting to go all SSD could find a similar device and put in up tp 4 SSD´s, the question is would it be viable in the Super USB Chain ecosystem?