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.

I have done that Paul.  I did not think it would work but it does.

Anthony

Yeah, I still prefer my ppa card with the subsequent modifications. 

Hopefully Peter will end his teasing and let us know what strange brew he has concocted to get the Silverstone sounding right.

Anthony

Vibration.  Squash balls under the NOS1 or something like that.

Ha, well I guess that is now confirmed!!

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

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.

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

Coen,

I've pulled the bracket from the PPA card and listened all day today and there is a general change for the worse in a similar flavour to the Silverstone, but only about 50% of the change that happens with the Silverstone.  The symptoms are quite similar but I think I hear only about half of the "buzzing without buzzing" that Peter started talking about. 

Regards,

Anthony

So, I have kept my isolated Silverstone in my XXHE PC for the past few days and have run the 5V from my lab LPS.  Peter, your quote above is quite accurate in my opinion now...this is a tiring sound...I was actually not wanting to listen to it and at times would prefer to sit in silence.  The "buzzing" without the buzzing analogy works for me too.  I don't know what it is but I can't live with it.

So today I put back in my PPA card with the altered transformer ground and directly powered clock (from my lab LPS) and it was like a wave of relief washing over me...the entire sound is "sweeter" and I hear more clarity and separation in the highs than the Silverstone ever offered, but the tiring aspect from the past few days is greatly diminished.

Regards,

Anthony

Care to elaborate Peter.  I am planning a post, but would now like to know what you are going to say!!

Anthony

Hi Peter,

If this tweak is such a big change for you, perhaps it may be worthwhile trying to measure a difference in noise at the balanced outputs or I2S or USB shield just to attempt to learn about the change.  It certainly seems as though there is potential for the tweak to be permanent if we can find a way to balance its negative effects.  Such big  changes do not come along often. 

I have a feeling that further isolating the USB card from the PCIe socket may improve the situation, but that is speculation on my part.  Or perhaps try a LPS into the 5V molex.

Regards,

Anthony

Glad you have it working Akremer!!  I am also glad that you notice a sound improvement.  Could you please describe the changes?  The picoPSU won't be causing the restarts unless it is faulty...I have used them before to good effect with no problems.

Peter, this is a reasonably common setup:  a relatively large, low cost LPS feeding a picoPSU into the motherboard and then smaller LPS's for the peripherals such as the SSD/HDD etc..  Depending on the version of the picoPSU, the 12V may be passed through to the mobo unscathed but the other rails are all derived via switching regulators, which sort of defeats the purpose to a certain extent, but it still is should be a step forward.

Anthony

Hi Peter,

I install the o/s on all of my computers using a usb drive that is setup as a boot drive because only one of the computers has an optical drive. 

My backup software is Acronis which allows me to make an "image" of the drive (or multiple images in time for that matter) that I can use to restore everything on that drive, including the operating system and settings, applications and files at a future date.  I have not had to use the restore function yet but I think that it may be one idea to get the functionality that you (or maybe just me) are looking for.  Just a thought.

If you are interested I can play around with the restore function to see if I can get it to work.  I have a handful of spare drives sitting around that I could use.

Anthony

Nice idea Peter! 

For those of us with spare HDD/SSD and a spare Windows license will you offer an image?  It would be nice not to have to purchase another drive and windows license and shipping. 

Anthony