XXHighEnd

Following on from a couple of other threads to do with the PCIe-USB card in the pc, this thread will look at isolating the PCIe-USB card as much as possible from the PCIe socket and the impact, if any, on sound quality.

To implement this, I purchased a $6 PCIe riser cable from fleaBay , read up on the PCIe protocols and formed a plan of attack.  The first thing is to divorce the power to the card from the PCIe socket.  The PCIe socket provides 3.3V, 3.3V Aux. and 12V whilst the USB Host Controller on the Silverstone card needs 3.3V and 1.05V.  Additionally the USB ports on the card need a 5V supply and this is supplied from an external source.

The pinout for the x1 PCIe connectors is shown in the image below.  The forward 11 pins handle power, connection testing (JTAG) and System Management Bus (SMB):  the JTAG and SMB functions are not required by a USB card.  Likewise, my aim here is to cut the power supplies from the PCIe socket in the computer, so theoretically the 12V, 3.3V, 3.3V Aux and ground pins are not required either.

With these things in mind I set about butchering my brand new PCIe riser cable to experiment with pins 1-11 on both the B (component side) and A (solder side) sides.  I cut wires incrementally and have determined the following things for the Silverstone card:

• The Silverstone card does not use the 12V or 3.3V Aux supply pins at all.  It only uses the 3.3V supply pins.
• The card does use the "Wake" pin, although this is an optional pin used for waking the card from low power states (ie. from sleep).  The "Wake" pin is the only pine used on the B side of the card (the component side).
• The only pins used on the A side (the solder side) are the "PWR Good" and "PRSNT1" pin (use to determine what size card is attached to the PCIe socket - in this case a x1 card)
• If I supply 3.3V from my lab LPS to the PCIe pins, and return the ground via pin 7 the card runs perfectly.  Note I also have 5V feeding the molex plug.

So, it can be done...I am now powering the Silverstone card from two rails of my lab LPS and it functions perfectly.  The orange pins from 1-11 on both the A and B sides in my PCIe pinout below are the only ones connected to the PCIe socket (every pin 12-18 is still connected).  Pin 7B goes to ground in the 3.3V rail of my lab LPS, and pins 8B/9A/10A all go to the positive.

How does it sound?  I will leave that for another day because I have only just started playing music through it, but the signs are promising.

The next step is to fiddle with pins 12-18.  All of these pins are required (CLKREQ would not be required if the card only supported a high power state i.e. always on) but there are 6 ground pins which depending on the design of the Silverstone card may or may not be related to the data operations of the card and not the power operations.  I will look into it.

Cheers,

Anthony

I found a little more time this afternoon and managed to have a hack at pins 12-18 on the riser cable.  Have a look at the attached diagram (orange are the pins connected between the PCIe socket on the mobo and the Silverstone Card)...ground is now _completely_ severed and power is now completely supplied from my lab LPS (3.3V to the PCIe pins and 5V to the molex plug).

It's probably placebo...but 5 minutes in the sound in freakin' awesome.

Can somebody else have a go at this?  You will need a two rail supply and a cheap PCIe riser cable.

Anthony

EDIT: There is a better image attached in the PDF file.

Hey Anthony,

I didn't read your text yet, but is it possible that you downsize that large picture (width 800 or so) and put that as *additional* attachment ? Put it in as the first attachment (so detach the other two (in the first post I mean), start with the downsized and then add the other two again.

Navigation in such a large picture is almost undoable (per this forum means), but works quite well if you can see where you want to navigate to *first* (that's why the smaller picture).

Will dive into the content later ...
Peter

Done Peter.  I have to remember that not everyone has a couple of giant hi-res screens in front of them...that image fits on the page on one of my screens.

Anthony

Ah super Anthony. But notice that you can (or should) just attach that large picture as the third attachment now (might people want to see details).

Btw, I already noticed that you have a nice camera there ...

Peter

Btw, here is something I had under my sleeve since two days, and I should have put it up right away; It is from Silverstone Taiwan and the most useful part you already found yourself (12V not used at all) :

(do notice : this is a response to what has been read in our forum about the card and is not much about my explicit questions (I asked for the schematic which they won't provide))

---

However you request about the power current for the USB port, since EC04-P does not limit the power current in each of the USB port, so in theory it can be based on the maximum power current which is provided by the power supply to use, but the user must  consider the USB connector has to withstand power current the restrictions to the standard USB 3.0 interface as standard power current term, usually its typical power current is 1.8A for each USB connector.

---

and

---

Notice for this user., our EC01-P/EC03-P/EC04-P used PCIe 3.3V to convert voltage to host ic(NEC) and molex power connector provide the 5V power to each USB port and we didn't use 12V power for these models.

---

Ha, well I guess that is now confirmed!!

Hi Anthony,

Its a miracle this works. Except for the tx and treceive lines that are balanced all other pins are referenced to groud. Without a ground the voltage cannot be determined. I expect that a pin that is 'low' provides the grnd connection necessary for operation.

I would be really concerned about ESD between card and mobo as there is no other path to travel besides the 'hot' pins.

Did you reference the powersupply to any pc ground?

Regards, Coen

Hi Coen,

I am surprised this works too.  Not only that but it works straight away.

The lab LPS is plugged into the same power socket as the rest of the audio gear including the pc, but other than the four wires running to the Silverstone card there is no other connection.

All I can say is that I ran this for a few hours last night and did not have any issues and that it sounded great.

Anthony

EDIT: The two PRSNT pins are directly bridged on the PCIe card so that the PCIe Host Controller on the mobo knows what sized card is in the slot, so these two pins are not referenced to ground on the PCIe card at all.

So I have done a little bit of listening this afternoon and I must say that the change for me here is as big as minimising the o/s.  My friend Dave was here as well.  Dave is a music lover but not an audiophile (lucky bloke!) and has a good ear for music but does not spend any time reading a audio or visiting forums and such.

Anyway, Dave was convinced of the changes in my system with this tweak and heard them pretty much as I did.  His most telling comment was that it was just "less noisy - more clear".  My own comments are significantly increased clarity with a speed and separation that is easy to hear particularly in the voices and with normally harsh instruments such as the cymbals and bells.  Remember this is with an isolated Silverstone card, which I did not like initially, but with further isolation from the PCIe bus the sound is sweet and delicate and dynamic and beautiful.  The "sssss's" sizzle and decay but don't bite. 

But the most important improvement for me is the "presence"...I am getting more nuance, micro-detail, clarity and believability.  It is a beautiful sound and a major step forward in my system.

So, what is causing this?  Is it that the ground for the USB card is now separated from the XXHE pc?  Is it that the cheap lab LPS is injecting cleaner power into the Silverstone card which in turn is helping the USB Host Controller IC and clock to perform more optimally?  Is it a combination of the above?  I don't know.  All that I know is that it is a major step forward in sound quality and it is something that I can make easily and it is something that Peter could also make easily.

My next thoughts are to the dexa clock guys.  Can you give this a try?  I will post a more detailed procedure to get this to work.  What I want to know is if this further isolation of the UCB card improves your sound with the clock mods.  If there is no change then we may be able to say that the clock mods account for the just about all of your improved sq and my isolation scheme is not warranted in that setup.  What I would like to hear (but of course I want the truth) is that this isolation scheme helps further with your setups and that the clock quality is not the be-all-and-end-all, although that would make things easier!!

Cheers,

Anthony

Hi Anthony,

Did you disconnect the chassis ground wires in the NOS1 like Peter suggested in the " best sound ever"  disconnected ground thread?

If you didn't its about the USB grounding wire from the USB receptacle to the PSU and the one from the PE to the chassis.

regards, Coen

Hi Coen,

There are two of them to disconnect ? There is one that I disconnected from the printed circuit (it is attached to the upper right screw in the right branch when facing the NOS1), but the other ?

Regards,

Alain

The other runs at the power connector end of the right leg (fron facing) to a screw at the top of the right side of that leg....

regards, Coen

Hi Alain,

Before opening my NOS1 I wonder if you noticed something after disconnecting the cable.

Incidentally, I think you just have to disconnect the black wire to avoid doing so in the USB cable that is more difficult. At least this is what I understood from Peter posts.

Best regards,
Juan

Edit: these are Peter words: "under the top right bolt of that PSU is a black wire; unscrew the bolt, detach the wire (it is not soldered), ...do NOT detach it from the USB interface as of now because it is too fragile there."

H*ll no Coen. I never said anything about the wire from PE to the chassis ... Leave that be please.

Peter

Hum... The "thick" guy that I am is now confused :( I will post a photo later to show what I did... It will be easier for all to see if I did the right (or wrong) thing...

Alain

ok!

(misunderstanding: in my NOS1 the USB grounding was attached to the PSU board with a little screw not a bolt like the PE wire)

regards, Coen

I think that you described it better than I... A screw yes, attached to the PSU "board", not the PSU itself... Anyway, will post a pic later...

Alain

Hi Anthony,


I just may give it a try but I do not have a power supply. I do have a linear 5v supply for the Molex and a 3.3v regulator. So I would have to find something to drive the 3.3v regulator it should not be impossible.

If I were a betting man (I would be willing to bet Peter another bottle of whisky on this ha ha) my hunch would be that it will not affect the sound when the clock is a Dexa. The clock output of the Dexa is isolated & floating. The power supply is the Dexa and it too is floating. OK I know that is not the whole story but as this has to be all about jitter...........

Nick and I have discussed a couple of times that the Dexa improvement could be about power supplies but there again who knows?

Anyway I cannot do this straight away as I am busy just now but as soon as I can I will have a play.

Cheers

Paul

Hi Coen,

No.  I have not disconnected that wire.  I will try it at some stage.

Regards,

Anthony

Hi Paul,

It would be much appreciated if you could give this a go.  Perhaps you could use a battery?

I _think_ that at least some of what I hear is to do with grounding rather than linear power or clocks, but who really knows at this stage?

Regards,

Anthony

Coen, remember, we are Dutch. We try to speak Dutch (dufficult enough already) and try to bring across what's intended. Now :

We as poor Dutch make the first mistake in naming a bolt a screw while it really is a bolt. Or ?
A screw drives into wood and a bolt needs a nut (or tapping).
We tend to differentiate between that small bolt and the larger one by naming the small one "small bolt" but with one word which doesn't exist in English (in Dutch each noun can be made smaller by means of adding "je" to it, so, bout (bolt) - boutje (small bolt).
Inherently we tend to call the small bolt "screw" (but still the small version - schroefJE) but we will never call the larger bolt a screw (young children maybe).

Peter


PS: And then there's also the parker (a screw which drives into sheet metal with same diameter from end to head).

Hey,

I have been staring at this in stages, and I suddenly might see some key in Coen's remark here. So what about those differential lines now NOT being connected to ground (adjacent pins not connected anymore) while in the normal situation they would be and which is WRONG. Well, not the best.

What about those differential lines creating ground, while that ground could be used at the other side (on the card).

The other remark/question I can make/have is :
Is the card still running well when no USB cable is connected to the NOS1 ? If not, the ground comes from that side (obviously).

It is not formal thinking that it is allowed to let come the ground from elsewhere, though still (in my view) it can be for the better "depending on". Just think about what happens when two different potentials are bonded. So in this case it can be mobo ground vs (lab) PSU ground. Both won't be the absolute truth were it for absolute zero ground reference; only differential will do that (absolute middle). The fact that differential is involved is already fishey because it won't be the same as the other grounds. Notice though that I assume(d - also in text above) that the differential signals *form* ground, which is not necessarily true I think. Anyway :
When two potentials are not the same, a current flows.

Of course, you can try to be ahead of this all and bond all grounds as much as you can, but all you will be doing is shifting the problem out of the device (like towards NOS1 in this case).
Compare this with a cut ground between two parts of the device, but now the "no ground" comes from the other device (NOS1). I personally think this is for the better. But it depends where the ground is cut.

Peter

Hi Peter,

Following is some information extracted from an Intel Powerpoint article about Differential Signalling (http://download.intel.com/education/highered/signal/ELCT865/Class2_10_11_12_Differential_Signaling.ppt):


So, it seems as though the differential pairs can be used successfully between pcb's of different and varying grounds (which is lucky) so I doubt that they ever were connected to ground on the USB board (not directly anyway).  The differential pairs all go directly to the USB Host Controller IC which according to my understanding has separate ground (or at least separate sections for analogue and digital).

I will try your suggestion about pulling the cable from the NOS1 to see if the usb still works shortly and let you know the results.

Anthony

Peter, I just un-minimised the o/s (with the NOS1 unplugged) plugged in a USB drive to the Silverstone card (with my further isolation) and Windows Explorer opened up with the contents of the USB drive.  Unplugged the USB drive, plugged in the NOS1, changed XXHE to the NOS1 (from Primary Sound Driver) clicked play and am currently listening to music.

So the Silverstone with these isolations works as a normal USB port.

Anthony

Great finding Anthony  :good:
So next (elegant) step would be cutting the traces on Silverstone card itself (at gold plated leads) iof using PCIe extender, isn't it?

Possibly.  If the traces were cut then we would also need to use the "condom" to separate the faceplate from pc ground, but that can be done.  Then there are experimentations with clocks on the card, which seem to be beneficial.

Tonight I have managed to figure out that the "CLKREQ" wire can also be cut which leaves only the "Wake" and "PWR Good" wires that have a signal to the Silverstone card (apart from the differential pairs).  I know that the "Wake" pin is optional in the PCI Express standard and therefore can be made redundant, but I need to do a bit of experimenting to see whether I can tie this pin to the PC ground (i.e. not connect it to the Silverstone card).  Then there is the "PWR Good" pin that I may be able to link to the lab LPS but I am not sure about that one.

Anyway, there is still a bit to figure out.

Anthony

Hi Anthony,

Your test with the USB disk is not right I think;
Now *that* can provide ground ... (uhm, assumed it is self powered I guess).
What I meant to try is to just have the card in and see if Windows still recognizes it. Don't say "yes of course or otherwise the USB disk wouldn't have worked" because plugging in that might just get it working.

Otherwise let's not make too much fuzz about this, but we can reckon that if it's NOT working anymore we have to change our thinking somewhat ...

Peter

Sorry I was not very clear Peter but it was a flash drive or USB stick, one of those finger sized devices that run from the power of the USB port.  I don't think that this invalidates the ground test.

Anthony

Ah, OK Anthony !
Peter

Anthony,

If you unplug the NOS from the USB 3 card, what is the voltage difference between the card (screw/parker of the bracket) and the PC's housing?

I would guess it is about 0V. Somewhere the circuit must ground itself on one or more of the active pins.
The differential inputs on the PCI-e USB chip are not galvanically decoupled from the motherboards PCI-e lines by x-formers or opto couplers. That means that the USB chip does not really allow for a 'large' common potential (like floating found) ; they must be just two single ended inputs (and feed lines).
Btw in this setup you still retain all the noise suppressing and improved transfer properties of balanced transmission lines.

Anyway I think the effort of reducing the number of possible ground return path is worth the pursuit. But this setup feels one step too far, it could potentially blow up your south bridge.

regards, Coen

Hi Coen,

As you suggested, I just measured the voltage difference (between one of the faceplate screws on the Silverstone card and the PC chassis) a couple of times now and measured about 240mV and 300mV.

I have a couple of further mods to make to the arrangement and I will let you know how that goes and what I measure when they are in place.

Regards,

Anthony

What an eventful day!

First off, I further refined my PCIe riser cable to the bare minimum.  All that I have left are the two sense pins (PRSNT1 & 2), the “PWR Good” pin and the three pairs of differential signal pins.  I tried to link “PWR Good” to the lab LPS (it is a 3.3V stable signal that currently comes from the mobo) but I have not been successful, and I think that it has something to do with power up timing.

So, I got this working, pulled it out, did Peters mod about unhooking the USB earth wire in the NOS1 and listened for a while with the Silverstone sans faceplate.  This is a nice sound, I like it, but I sat there with a grin on my face because only this morning I had been listening to my PCIe riser “loom”.  So I shut everything down, put my loom back in, switch everything back on…nothing…not reading the NOS1.  I tried all sorts of tricks to get it to work but in the end I had to reconnect the USB earth wire in the NOS1.  Turned everything back on and bingo…everything worked…music…and such beautiful music. 

Guys, this sound is FAR ahead of the anything that I have heard from the NOS1, the resolution is astounding… saxophones rasp, trumpets braap, the piano is so real, drums and cymbals are to die for and I can easily pick things that were not so easy to hear before such as when the drummer has his foot on the top-hat compared to when he just lets it ring.  With all this micro detail the nuance and musical cues jump out and it is a very satisfying listen.  The sound without my loom and with the isolated NOS1 and Silverstone by comparison is slower, thicker, much less resolving and much less enjoyable, but still great as far as the dacs that I have heard go.

So, I think that I have gone as far as I can with my loom.  In the next few weeks I should have some really high grade LPS (from the linear ATX project) that are super low-noise and wide bandwidth.  I will keep playing music through my loom until then just to see that it is stable.

There are two things that might be indicators of what is going on ground wise:  I could not get the “PWR Good” to work at all when it was connected to the lab LPS;  I could not get XXHE to recognise the NOS1 when the loom was in place and the USB earth of the NOS1 was disconnected. 

The ideal way forward (after others verify my results) would be to design a USB card from scratch which:

1.   Severs ground and power from the PCIe socket, probably more elegantly than this loom achieves it.

2.   Accepts high quality power supplies, maybe even batteries.  Card consumption is about 0.4W so batteries should last for ages.

3.   Uses a high grade clock, possibly with its own power supply


I do not have the expertise to design such a PCB although I know how everything needs to join together.  As an alternative, it would be possible to build an external box to hold the Silverstone card and the power supplies and make up the loom from the PCIe socket to the new box.

Anyway, I would love it if someone else gave this a try.  I will provide instructions in my next post.

Cheers,

Anthony

INSTRUCTIONS TO BUILD A PCIe LOOM

To complete this project you will need a PCIe riser cable (like this one (http://www.ebay.com.au/itm/250845534252?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649)) that you don’t mind taking a knife to, and a dual rail lab LPS (or a dual battery supply).

Have a look at the PCIe pinout diagram below…see those orange pins?...they are the only ones that will hold a wire when we are finished.  “B” side of the Silverstone card holds the components, and “A” side has solder everywhere.
 
STEP 1:  Test to see if your new riser cable is functional.  Plug the riser cable between the PCIe slot and the Silverstone card.  Turn on your computer and play some music.

STEP 2:  The cable is functional in its standard form so now carefully take note of which is the A side and which is the B side.  This is really important because you don’t want to be pulling off the wrong wires.

STEP 3:  Isolate and cut all three of the 3.3V (B8, A9, A10) wires on the riser cable.  Strip and twitch these wires together (the cut wires that go to the Silverstone card, not the cut wires that go to the PCIe socket) pull out your soldering iron and join those three wires to a new wire that will become the 3.3V positive wire to the LPS.  Do the same to the three ground wires on the front section (B4, B7, A4) and join them to a new wire that will run to the 3.3V negative terminal of the LPS.

STEP 4:  You are now left with the lower half of the cut 3.3V and ground wires that are attached to the small pcb that fits into the PCIe socket.  These must now be removed so they don’t flop around and cause a short somewhere in the computer.  I was able to carefully pull these wires down so that they pulled out of their solder on the lower pcb…you should be just as lucky.

STEP 5:  See all of those other wires that are still connected to pins that are not orange in the pinout diagram?  Well cut them all and pull them off both the bottom and top PCB’s of the riser cable (don't pull the 3.3V and ground wires that you just soldered together from the top PCB):  they are not needed any more.  You will have to use a sharp knife to start a cut between the wires in the ribbon and then simply pull them apart with your fingers.  Do NOT separate the wires of each differential pair:  each wire of each pair is best left joined to its mate so that noise cancellation is improved.

STEP 6:  You should now have a riser cable that has been reduced to just nine wires including three differential data pairs that are joined.  Turn off your pc at the wall (or on the switch on the power supply that completely turns off the computer), put in the riser cable, plug in the Silverstone card to the riser cable, place something between the Silverstone and the pc chassis (under no circumstances is the Silverstone to touch the chassis while it is “live”) plug the 3.3V wires from the loom into one rail of the LPS that is set for 3.3V or 3.4V.  Plug a power cable into the molex plug of the Silverstone card from the LPS that is set to supply 5V (do NOT use 5V from the computer power supply).

STEP 7:  You now have the riser and Silverstone card installed along with two sets of wires to your lab LPS that is set for 3.3V and 5V.  Turn on the lab LPS.  Turn on the back switch of your XXHE computer.  Press the start button on your computer and it should boot up as normal.  Start XXHE, press play and listen to music.

STEP 8:  Let me know what you hear!!


Cheers,

Anthony
 

Hi Anthony,

Thanks for the elaborate instruction.

In the diagrams I see that the data receive is not dc coupled, but the data transmit and bus clock are. Likely the are decoupled at the end of the bus.

So we can conclude that the NOS1 case connection is crucial for the ground reference. Do you have the PE connected to power earth for both the pc and NOS1? Or maybe the amps PE?

It seems like a favourable grounding scheme to reference ground at the end of the chain.

Regards, Coen

Hi Coen,

Yes, I think that the NOS1 case connection is crucial for ground reference with this setup.   

Here is an excerpt from the PCI Express Card Electromechanical Specification...


So decoupling is a requirement of the PCIe standard.

I use 3 prong power cords all components (the lab LPS, the XXHE PC, the NOS1, the amps) and everything goes into the same power socket which is a dedicated line for audio.

Regards,

Anthony

And didn't I say that THE difference with the other cards is the lack of electrolythes ?
Don't ask me what those are for on the other cards, but it would be my exact point of attention in this realm, and the smaller the better (like 402 being better than 603 for such an application). Eh .. aha ?

Anthony,

General remark : I think most of us will be using the NOS1 without PE. This is just because I advise it *if* the subject is in order in the first place. But I often mention(ed) it in the forum as well.
Notice that this in itself is totally UNrelated to that black wire being mounted or not (no matter you'd think a 100 times "so, what is it for then without connection to PE in the first place").

Regards,
Peter

Another general remark : Super !

Which makes me think that you're explicitly using PE for signal ground in this situation. But when the whole story is taken into account, it also works the other way around : when all grounds are connected as should at the PC end, now USB signal ground goes over PE. Or at least it can (whether really so depends on many things).

Question (and maybe I should read back all the details) :
Anthony, do you now have an understanding of what ground you are really using ? So, still it has to come from somewhere (and you've proven it's not the USB cable).
Any one-liner for this ?

Thanks,
Peter

So, this all makes sense after all.

When Anthony isolates (or disconnects) the NOS1 PE (at the power cable/connector end) it does not work anymore. And be careful with static!

regards, Coen

Yo Anthony,


You'll remember my :secret: connection which doesn't want to work without clear reason ? You may not want to believe this (I dare not te believe it myself at this moment), but it can well be that you just handed me the reason ...

That connection too is isolated (think no bracket);
Skipping a few things I don't know (or didn't sort out back then - like what pins exactly provide which), in MY situation the black wire in the NOS1 was there all right, but PE is not provided (using a 2 prong, say). Additionally, MY external PSU provision (part of the :secret:) does NOT provide PE hence nothing connects to PE anywhere and now I'm not sure. It's almost like PE will provide a ground path to the PCIe bus or something. Well, that will not be correct but what the heck is happening really. So, I'll be damned if my connection works after all if I only connect a few devices to PE (currently the PC is the only device doing that).

Can someone hand me an idea how additional (signal) ground over PE would be able to provide more current ? I mean, outside of what I said above, I have the idea that when something like what happened to Anythony (won't see the NOS1) this is about not enough current provided. So, way more current is needed to load the binary to the USB interface (FPGA in there). And if that current is not there sufficiently, just nothing will happen. Now I envision Anthony's situation (but could be mine as well) as something like a signal (plus) wire of certain gauge, ground is actually lacking but goes through tiny leaks up to through air or whatever illegal - that will let USB work in itself (card is recognized) but as soon as more current is needed (plug in NOS1) it's not enough. However, PE will provide enough always and nobody notices a thing about (design !) faults etc. because PE is to be there always.

Was this clear somewhat ?
:nea:
Peter

I'm using the 3 prong power cable you provided Peter.  I could find some two prongers to see what I can figure out.

From what I can figure out, signal ground is going out through the LPS, assuming that the isolation of the Silverstone from the PCIe socket is working as desired.  I wonder what would change if I lifted PE for the LPS by using a two prong power cord?  That is something to try.

Anthony

I do remember your secret connection Peter and if my experimentation helps you get your thingamy working then that is great.  I must say that I am curious as to what it could be!

Regarding your question about the current for the FPGA when the ground wire was disconnected in the NOS1 and the loom was in place I am not sure that the USB card was visible to the operating system at that time because I did not check.  It may have been.  Nothing for certain I'm sorry, although in hindsight I should have checked.

Anthony

Mystery ground connection left aside, I do see some similarities between my setup and anthonys.

Both make use of a fully connected usb interface, that is including the usb ground.

The other is the 'single' ground. If I am correct, the pe acts as ground for Antonys setup (like a star earth) and in my setup the PCs pe is the only one connected (think bus earth). This reasoning is valid only if on the pc side the pci-e ground is connected to the chassis which is connected to the pe wire and the usb groundpoint in the nos1 is connected to the case (wich is connected to pe by 'the other' wire).

I think we are hearing a very similar improvement though through quite different methods.

Regards.

Anthony, no problem. In my case it's certainly visible.
Peter

Well, I guess that I must have been doing something wrong yesterday when I tried to listen to music with my loom in place and the black earth wire removed in the NOS1 because today it works.  So I guess some of yesterday's theories are now redundant.

I don't know why I could not get it to work yesterday, but today it worked first time.

For clarity, I think that I should give a brief overview of the earthing arrangements of my system as it currently stands.

• The NOS1, XXHE PC, lab LPS and amps are all connected with three prong power cords into the same power socket which is a dedicated line for audio
• I have lifted the black wire from the NOS1
• The lab LPS is feeding 3.3V and 5V into the Silverstone USB card which has a special cable loom that attempts to isolate it completely from PC ground

Anthony

Well, you might be right here.  I have noticed a very intriguing phenomenon with the loom in place:  when there is music playing (NOS1 black wire either connected or disconnected) and I turn on or off one of the fluorescent lights in the room or even in the next room (through a brick wall) the music stops.  It seems as though the Silverstone usb card is no longer recognised by the computer and I have to stop XXHE from playing the music, turn off the computer totally and then turn it back on.

Normal light bulbs are no problem.  Remember that no lights are on the electrical circuit which powers the audio.

Unusual.  I have not experienced this before and will do a little research into fluoro lights.

EDIT:  The music does not go off when the fluoro light is flickering but it goes off when the light snaps on permanently.  When switching off the light the music stops straight away.

An Update.

So I pulled out my cable loom and have experimented with the fluoro lights.  Regardless of whether I have use my lab LPS to power the Silverstone molex or not, I get pops through my speakers that sound similar to samples being lost.  These pops occur when the fluoro light flickers on and then when it strikes permanently and then when it shuts down. 

So the lab LPS does not seem to be part of the problem, but obviously my loom is causing a greater sensitivity to the fluoro light issue.

Anthony

Solved.  I went into town and grabbed a digital ballast for one of the fluorescent lights to replace to magnetic ballast and starter.  Wired it all up, turned on the music flicked the switch...and...nothing...no pops...no music stopping...just how it should be.

But a nice lesson about things in the house that can impact your audio power supplies.

Anthony

Anthony,

Not solved I think. Better put back that "malfunctioning" device and with that as a measure find your lacking ground ...

IOW this is the *typicle* proof of lacking ground. Most probably your whole needed grounding comes from PE. Not good.

Make yourself such an extension block with x power outlets and cut the ground inside. Or better : cut it halfway when possible. So, the better ones have copper (bare) leads running along the PE points in the outlets, and if you cut that halfway then you can easily choose for PE or not (say 4 outlets now carry PE, 4 do not).

When not using PE for the PC now probably nothing works anymore (for sound). But maybe it does, because what your lights imply is changing the ground potential and that sudden *change* is not tolerated (comes down to e.g. 5V suddenly being 20V (or 0V) for a short period of time.
Remember, the more devices (not lamp bulbs I think) switched on, the more PE will lift. You can see this by means of two PE's (say two different earth pins), the one serving as a reference for the other.

Regards,
Peter

Hi Peter,

You are most likely correct that the problem is not solved.  The 30 year old magnetic ballast that I replaced with a new digital ballast in one of the lights is known for injecting large voltage spikes into the house wiring when it turns on and turns off.  The digital ballast is apparently able to suppress these spikes.  I have always had these pops when turning the lights on and off but never investigated them before.

I will play around with the power-board idea and let you know what I find.

Regards,

Anthony

So today I have played around with the earth arrangement of my audio gear.  When changing plugs I noticed how difficult the plugs were to get into the socket (very difficult) and even the switches were very difficult to move.  Also with one of the sockets, I could hear a buzzing noise when turning on a component so I was straight off into town and got myself a new power point and installed it before proceeding further.
The surprising result here was that my DC offsets in the NOS1 now settle closer to their optimum settings.

#	Silverstone Card	Black Wire in NOS1	XXHE PC	NOS1	LPS	AMPS	Effect of Lights
1	Isolated	Lifted	PE	PE	---	PE	Pops
2	Isolated	Lifted	PE	PE Lifted	---	PE	No Pops
3	Isolated	Lifted	PE Lifted	PE Lifted	---	PE	No Pops
4	Isolated	Lifted	PE Lifted	PE Lifted	PE	PE	No Pops
5	Isolated	Lifted	PE Lifted	PE Lifted	PE Lifted	PE	No Pops
6	Loom	Lifted	PE Lifted	PE Lifted	Lifted	PE	Computer won't start
7	Loom	Lifted	PE Lifted	PE Lifted	PE	PE	Computer starts but NOS1 DC offsets won't settle
8	Loom	Lifted	PE	PE Lifted	PE Lifted	PE	Pops then NOS1 loses DC offsets
9	Loom	Lifted	PE	PE Lifted	PE	PE	Pops then NOS1 loses DC offsets
10	Loom	In Place	PE	PE Lifted	PE	PE	Pops and eventually will lose lock with NOS1 which requires a restart but does not lose DC offsets
11	Loom	In Place	PE	PE Lifted	PE Lifted	PE	Pops and loses lock with NOS1 which requires a restart but does not lose DC offsets
12	Loom	In Place	PE Lifted	PE Lifted	PE Lifted	PE	Pops and will lose lock with NOS1 which requires a restart but does not lose DC offsets
13	Loom	In Place	PE	PE	PE	PE	Pops and will lose lock with NOS1 which requires a restart but does not lose DC offsets

Sound with the loom in is preferred to sound with the loom out.

Hope this helps.

Anthony

Great work Anthony!

I think we may conclude that the Loom does not provide for enough grounding connection to make it work without some annoyance. This must have to to with an uncertain ground potential between the card and the motherboard.

Now what if we could actively FULLY isolate the PCIE card like with some fast opto couplers....hmmm...

I wondered: why didn't you experiment with the power amps PE disconnected? Than there will be no more (redundant) ground path via the power amps. Anyway this would mimic my setup (as an alternative to 2).

regards, Coen

Anthony, man, what have you all done !
Well, at least this proves that I myself have been working on a couple of things in the past and how the DC Offset metering got in; it forces you to have it correct (to some extend).

Now I must really digest all the combinations. So I will.

Peter

PS: Notice that Coen is correct to best avoid PE for the power amps. At least that is my experience over and over again (but it will not be a real rule).

The DC offsets made it easy actually.  When they are not fixed and music is playing it is a quick dash to the amp power switch but after the first time that happened I actually turned off the amps when testing the lights and just watched the DC Offsets.  If it proved safe after a dozen switches of the lights or so I would turn the amps back on and listen for pops.  I learnt a lot in the process.

I will try the amps off PE at some stage but I thought that if I messed with them yesterday that I would have double the amount of testing!!!

Anyway, a few things came out of this I think:

• The loom does sound better.  This could be the dubious ground loops or the LPS or both
• The NOS1 should be run with lifted PE.
• If the loom is used the black wire in the NOS1 must be connected

Anthony

Anthony,


I made a remark about this when you wrote this, but (sadly) I scratched it because I drifted off in that particular post (so the whole post wasn't posted). But my remark about this was :

The sizzle is a tough one to interpret;
For me it could be an indication (and I mean when I perceive that myself) that some higher frequency is riding on it all which make the S sizzle. Btw, same can happen with a nylon string although I'd call that "zzoooming";

In both cases (S and nylon string) this *is* a good characteristic and at least for the nylon string I will not be able to discern the better and the worse. To understand this, we better look at the sizzling S and try to see how much real that would be. I mean, try to produce that sizzle yourself; you will be able to do it, but it won't be easy (it's even hard to hear it yourself and another person needs to listen).
Now, when you have tried this and have seen how difficult it is, you can come to the conslusion that what you perceive from a random track with random singer with his/her random S that sizziling is not likely. Also, it needs "Z" to be incorporated which is why it hardly can be a natural S you're hearing.

This has been my perception for a longer time, but I must say that I never really "tuned" on it, because the sizzling seems to exhibit better resolution/resolvement and audibly it is not disturbing. Also, combine it with the nylon string which gets better from it (plus better discernable from the metal string) and you are fine. Still, when the chips are down like in these posts (about PE and such) I think it should be (?) a measure of the wrong. And of course it is placeboed in my mind because of no ground = no good.

It's only sad that I scratched this text at the time I wrote it which was way early in the topic because then I would have been predictive while now it seems in aftermath. But really not so.

Btw, I now wrote it after all bcause I tried to make a best choice of your table of happenings which I couldn't. So the best choice would be one which plops with your solution of not switching the lights but which right away also prooves that PE is used for signal ground. Notice that "signal ground" is of various types, only one of them real (music output) signal ground and you can see it by the DC Offset changing or not locking.

What I only start to recognize is how a PC itself can be the baddy in this all, because I can see that I myself can't get things wrong at this moment, while the whole (DC Offset) setup has been created with another PC which *did* have problems like not wanting to start. Not much useful for you all, but this same PC ended up elsewhere (not for music playback) and when it was powered down I had to ... detach USB devices (like a printer) before it ever wanted to boot.
I can also add the fairly unrelated (or not) happening that half a year or so ago, we were struck by direct lightning and everything survided expect that PC (main earth switch tripped). After that it never wanted to boot again and it was replaced.

Remember, it is only today that I am able to combine these things (or suggest they are related) and it can only happen from more "sightings" from guys like you, your experiments and your descriptions of it.
These things are mighty difficult and even while I'm focused on it, it apparantly takes years to nail it down. To some extend that is, but we won't stop experimenting.
Personally (but I don't see all) I think that the few forums posts in here - relative to say millions elsewhere - are so much more valuable than these millions of others.

Peter

Hi Anthony,
Thanks for the loom description. I have the loom running now, but I prefer it with the (modified) Paul Pang card. Because with that card I like the (less) highs more and ALL details are there!
I have a second Silverstone and PP (in order) and will make a combination of the two.... See what that will bring.
And W7 is also really nice to hear again.....
Regards, Arjan

I suppose there must be at least one component connected to PE - so it would be the PC and PC only ?

Alain

Hi Alain,

Not that I know of, athough it seems to derive from logic (of the posts). It *is* true though that in my situation the only thing which can be connected to PE is the PC, while that measures better. So can indeed is must - in my situation.

Regards,
Peter

Hi Peter,

Yes, I can imagine that “sizzle” means different things to different people, but I most definitely do not mean it in the way that you understand it.  I will give you an example.

I like trumpets:  they are a relatively simple instrument that is brash and raspy and difficult to play (no I don’t play one).  I also like drums because growing up my neighbour was a mad drummer and I would go over to hear him thrash out Van Halen or whatever was popular at the time (actually I did not have to go next door to listen to him play…hehehe).  The cymbals are what I remember from those days how they were just on the edge of being abrasive and how he would manipulate them with the stick or brush or hand or foot to change the sound.  So I think that I am reasonably sensitive to the sound of these instruments.

What the Silverstone card in its fully isolated form gives me is more of the realism of the drums, cymbal and trumpet.  For example, to my ears there is more change in the sound of the cymbal with each strike.  A more fleshy strike, a rapid change as the cymbal recovers from that strike to vibrate evenly and then decay.  What I hear in most systems is not so much of the fleshy strike, but plenty of the vibration when the cymbal has recovered and then a form of decay:  in other words more of a “one sound” rather than the more graduated sound that the Silverstone gives me.

Likewise with the trumpet.  A trumpet has rasp and a much varied tone depending on how it is blown, and the isolated Silverstone (both ends) gives that to me better than the PPAstudio card but the sound is still rough to my ears, too harsh (like there are higher frequencies involved), not entirely right.

What the loom does for me is take a lot of that noise or roughness away and gives better clarity, more separation between instruments (a blacker background if you like) and more resolution (read: more fleshy drums and raspy trumpets).  I have not mentioned voices in all this at all, but voices improve remarkably also.
 
Peter, I think that you are right with your observations about signal ground.  What I plan to do when I get some time is to re-solder some of the ground wires onto the PCIe riser cable (my loom) in an effort to reinstate that connection.  I have an idea that with my loom at the moment I have taken two steps forward and one step back.  Perhaps all that I need to do is get linear power to the card (or possibly to the clock itself) which would equate to two steps forward, and not sever the grounds entirely (my one step backwards).  The Silverstone needs to be resistant to my fluoro lights and if I am right the best sound may just coincide with this as well.
More to do.


Best Regards,


Anthony

Great description Anthony.
And your description about the cymbals makes me think that you really must try W7. W8 makes exactly that evolvement of the cymbal unbalanced.

Regards,
Peter

As I (and some others) cannot hear any difference by isolating PCIe card and the USB at NOS1 - could that mean there is a more fundamental problem to be addressed in cases where it does make a difference?

Just a thought?

Maybe Paul. Who is that "some others" ?

Hi Arjan,

Great that you got it working!!  Did you use a LPS for both 3.3V and 5V?  Did you have any problems with pops like I did?

Once again, I really appreciate that you gave this a go. 

Regards,

Anthony

I will give w7 a go and am sure there is a spare licence kicking around here somewhere.  I came to XXHE once you had sorted out w8 so have never listened to w7 and XXHE.

Anthony

Hi Anthony,
I use a separate lps for the 3.3v and the 5v goes via picoPsu powered pc by another lps. So everything on linear power.
I do not have more pops then before, only my doorbell is (and was).
But plugging in another usb on the same card stops the music. So it is more tricky now. But it works fine!

You should try W7! W7 is more relaxing were W8 is more realism with some too agressive highs. But maybe better for another thread about W7 and W8.
Regards, Arjan

Nick & I played around with isolating the USB card and USB plug at NOS1 about a year ago but as neither of us could hear significant differences we did not proceed. Nick felt he could hear small differences but nothing much. IIRC Todd mentioned that he did not hear any difference either.

Anyone else? if so please post.

Nick & I both have balanced supplies and dedicated earth so our PE's should be low noise. Obviously I cannot know if that is relevant but worth mentioning.

So at least 3 of us but maybe more that have not posted.

I shall be going to Mani's when he gets his Orelino's (soon???????????) so we can try a few checks then (he also has balanced supply).

I have mentioned before but worth mentioning again here that at one stage I tried something crazy with my earth arrangement. My amplifier case is not connected to anything it is only connected to PE (the PE at that time was connected to NOS1 and PC and balanced transformer then all back to earth spike in the garden). So I then connected the amplifier case direct to the earth spike in the garden. I also connected NOS1 case in the same way direct to the earth spike (of course NOS1 case is also not connected to anything except PE). So as far as possible a Star arrangement.

WOW what a difference the sorts of changes you have described for the PCIe isolation. I was very surprised at the time I was not really expecting any improvement. Of course I cannot know if that is relevant but also worth mentioning.

Paul

Hi Paul,

I would be interested by what you actually tried about a year ago.  Did you try something like my loom that disengages the ground between the PCIe socket and USB card and allows cleaner power for the card itself?  Or did you do something else?

Regards,

Anthony

Hi Anthony - we isolated the USB shield at NOS1 (actually with some teflon tape) end also we isolated the PCIe ground at the PC (the bracket we covered in electric tape). That's as far as I went but Nick went further by isolating the earth on the backplane as well (IIRC). Obviously that was before we fitted Dexa clocks. Nicks feeling was that there were small changes in SQ but he found it difficult to decide if they were improvements or not and also (again IIRC) thought that the changes were inconsistent. So further investigation was dropped!

Neither of us tried the PCIe card on a riser cable with independent supplies.

The only other thing I tried (and I think Nick also) was to install a linear 5v regulated supply for the molex on the Paul Pang card but that sounded significantly worse (covered in detail in separate thread).

That's as far as we got.

Cheers

Paul

Hi Paul,

There is a difference with the 'USB ground disconnection' in the current discussion. This is about the isolation from the power supply (and chassis) by removing the connection of the black wire from the USB receptacle at the power supply's end.
In this situation, the USB cable's shield remains connected to the USB circuitry at both sides.

This might not matter to you at all, but I thought it worth noticing.

regards, Coen

Hi Coen,


Do you mean the black wire (or blue in my NOS1) that runs from the USB female socket shield in NOS1 to PE (via a screw to the case in the right leg power supply)?

If so yes I did remove that and again made no difference.

Paul

Hi,

Iv been following the thread but had decided not to say much, I'm not familiar with the silverstone card and although the stuff I tried (below) was not conclusive that's not to say that there were not changes to sound. I found results to be quite system dependant so I did not want to comment too much because as it seems likely that we may experience the effects differently depending on the rest of the system.


IV destroyed a good may usb2 and 3 cards over the years trying similar things  :) Rather than use a pcie riser I traced the pins on the usb PCIe edge connector back to the bus pins and broken traces to inject power (LPS, batteries etc), disconnect PCIe earth and decouple cards from PC chassis earth, and DAC signal earth. Also tried clock mods and usb card component upgrades. Then there was galvanic isolation with the Anadco.  In the end it was thinking about results of experiments with the Anadco that lead back to experiments with usb clocks again.

Regards,
Nick.

Yes, as the only means of 'isolating' the USB. YMMV with these kind of tweaks. It all depends on (too) many other factors.

regards, Coen

So last night I re-soldered the wires in the loom for the ground pins on the x1 lane (A12, A15, A18, B13, B16, B18).  This has _completely_ solved my "fluoro light" issue.  So now my loom is delivering linear power directly to the Silverstone card but the x1 data lanes and grounds are all in tact.

I will listen to this setup for a while and then play with isolating the NOS1 USB with its black wire again.

See below for the current PCIe pinout for the loom.

Cheers,

Anthony

Bert, I moved your post to here : Re: XX Further Isolation of the Silverstone PCIe - USB Card (http://www.phasure.com/index.php?topic=2838.msg30313#msg30313).

Peter

I have now listened to the latest incarnation of the loom for about two days now.  To verify my findings I recenty removed the loom and ran the isolated Silverstone and NOS1 as so that I could hear the "reference" again.  All that I can say is that sound is well ahead when the loom is in place.  If I had to hazard a guess, I would say that the sound since I re-connected the grounds on the x1 lane is better than when they were disconnected.  Happy days.

It seems as though feeding cleaner power directly to the Silverstone card helps the sound.  Changes to the grounding arrangement of the card do not seem important from a sq perspective (apart from perhaps the faceplate isolation from pc chassis ground) so perhaps the improvement is as simple as providing cleaner power to the crystal on the Silverstone.  The only other item on that card that may be affected is the USB Host Controller IC.

Anthony

Hi Anthony,

Glad this worked out great. As a bonus your setup is a lot safer too!

You made me curious: today I wil have an adapter on e-order as local stores cannot supply.

regards, Coen

That's great Coen.  It will be good to get another opinion on this.  Peter nudge, nudge, wink, wink.

I will leave the loom in place for a while now and investigate windows 7.

Regards,

Anthony