Does Improving PC PSU and Reducing PC EMI/RFI Improve SQ?

[earflappin]

Hi All,
I'm new to XXHE, but became an instant convert when I heard 0.9y4 on my Zalman music server. 

Like many of us I have tried many tweaks over the years to improve SQ - some worked, some actually hurt SQ (1 step forward, 2 steps back) and others did nothing.

Recently, I did some experimentation with reducing EMI/RFI inside my Zalman PC.  Basically I took some ERS cloth (known for its EMI/RFI absorptive qualities), put it in a plastic bag (its conductive material!) and carefully encased my Lynx AES16 card.  The improvement was immediate.  Noise was reduced and SQ improved, specifically, richer tonality and increased micro/macro detail.  Has anyone else experimented in this area?   I've also put some ERS on my Zalman PSU with good results.  Next, I'm going to try putting some ERS on the IC chips on the Lynx.  The ERS is OK with high temp applications and the Lynx card doesn't run hot anyway.

Secondly, I've almost always found improving PSU (power supply unit) in components yields improvements.  I power my components with a PurePower 2000 APS which did great things for my SQ, but my Zalman PSU is just a stock switch mode PSU.  I would think, at a minimum, that the Lynx card would benefit from having a higher quality power supply, but the guys at Lynx tell me they don't think so....however, they also told me that added shielding wouldn't increase SQ.  Has anyone done work in this PSU area?
Thanks for sharing!

[Per]

Hi Earflappin,

Fun you mention it - I have also thought a lot about this. Actually I plan - when my health allows - to set up an external PCI expansion box that only contains the soundcard. Besides needing the physical strength to fiddle around with all this (I suffer from a severe muscle disease) it is also a rather expensive approach. A box like this from Magma http://www.magma.com/products/pci/1PCI/index.html costs about a grand (thats more than a hot-rodded PC!) I have though seen a noname box - for PCI express only - at around 300 dollars but the EU based company (I do not recall the name) never responded to my inquiry if a PCI interface card was available.

The idea about seperating the soundcard and the PC is - as I see it - that you can supply this box (and your soundcard) with a clean DC supply (12 volts) from a SLA battery or the likes. Secondly the soundcard sits alone in the box - totally awasy and shielded from the motherboard and other noisy parts of the PC. The only connection between the PC and the expansion box is the PCI / PCI-express interface cable between them. (There might be twists to this that I do not see a non engineer)

It would be very interesting to measure distortion and and noise on a soundcard sitting 1) in a PC vs the same soundcard 2) in an expansion box with its own DC (battery) power supply.

Another and more DIY approach could be to use a PCI riser for the soundcard in an ordinary PC, cut the 5 and 12 volts supply tracks on the riser card and connect these by wires to an external power supply instead. That would be a lot cheaper than an expansion box (if it works that is) The only thing that this solution would not do is seperating the soundcard from the noisy inside of the PC. But that could be had if you'll be radical enough to extend the PCI riser out through PC case having the soundcard sitting in a cage outside the PC - much like you see with tube amplifiers! That would look pretty cool, I think  The only problem with this radical approach would be whether the distance between the soundcard and the motherboard would be too long but with the right case it should work - maybe a mini or low profile (1) PC case.

Now I got this out of mind (for now) - so thanks for bringing up the subject of EMI / RFI / Power supply, Earflappin. It has been a pleasure to read about adventures with setting up XXHIGHEND.

Good luck to you and all - and please keep us posted on the results I personally would love to know if anyone has actually tried the expansion box approach to the soundcard and if they actually gained sound quality improvements from this.

Best wishes,

Per

[earflappin]

Per,
Thanks for your response and best wishes on your health.  Do you live in Sweden by chance?  Love that country - used to live there as an expat years ago.

I have considered the approach you suggested about using a riser and use a battery to provide the power to the Lynx card, as well as using a separate box to remote mount the sound card.  Do you know if there are any sync issues with these PCI/PCIe sounds cars?  I.e. is it okay for the cards to be powered up and down separately from the mother board?  Bottom line, I am game to invest the time and $$ to try this, but could use some help in being sure I specify the right parts.  Personally, I think there is a reasonable boost in SQ to be had by doing this.  And this approach would be alot less expensive that trying to provide the entire PC with power via a linear power supply for example.

So...what would you suggest as a battery for power?

[Fidelio]

Thank you for starting an interesting thread. Using an internal card as my source, I relate very much to this issue.

Personally, I have not experimented with internal isolation, nor with PSU mods, but I have discovered big differences in sound with different mainboards. I suspect this is mainly due to quality differences of the power delivered to the card. I think mainboard power quality is more important than PSU quality; I cannot hear big differences between PSUs.

[PeterSt]

Guys, you won't get much cheaper than the Magma, and you can bet I spent time on this one. Besides, people claim it may not help all that much because of the hight frequency of the PCI bus itself.
I think I recall the PCIe solution as being cheaper, but I forgot what is wrong with it. Something is though (but maybe I just couldn't use PCIe at the time ).

The riser "cables" won't make it to outside of the PC because everything you can buy is too short (say 7 cm or so max). Maybe with some DIY it can work though ... I don't know ...

May one of you go the route of external PCI, keep in mind that the topologies used for it differ quite a lot. One can do 10 meters, another 100. One uses DVI, another Cat5 (or 6).
One box can hold 1 card, another 16 ...

Peter

[earflappin]

I found this on-line for $400.

http://www.startech.com/item/PEX2PCIE4L-PCI-Express-to-2-PCI-Full-Length-2-PCIe-Single-lane-Expansion-Box.aspx

I did live chat with them, but they were unable to suggest a supplier for a compatible battery power supply.  Anybody know where I should look for that? 

Thanks!

[Fidelio]

I think it is cheaper to invest in a motherboard that supplies really good power to the PCI slots. The new Gigabytes are brilliant in this respect by the way.

[earflappin]

Thanks Fidelio.  I use an Asus P5Q-EM 775 G45 RT.  This was the recommended mobo for my Zalman fanless TNN-300 chassis.  Not sure how it's power delivery system rates.  Again, I am just hypothesizing that better power to the PCI card will improve SQ.  Since I've not come across anyone who can validate this hypothesis I think I'm just going to have to give it a try.

Looks like the PCI card needs +12V, -12V, +5V and +3.3V.  Magma does offer an option with an XLR4 to 12V cable so you can provide power from a lighter or 12V battery.

[AUDIODIDAKT]

I think it is cheaper to invest in a motherboard that supplies really good power to the PCI slots. The new Gigabytes are brilliant in this respect by the way.

I have made this exact change some months ago, went frome GA-EP35-DS4 to GA-EP45-EXTREME (overclockers-board)(both Gigabyte)
This improvement was quite BIG !
Did not expected that to happen, but it really does.

Roy

PS: the more of those black square cubes (or how do you call them!)(for power supply) on there the better.
      (look at the black square blocks around cpu)

[earflappin]

Thanks for the input.  I'm checking to see what Gigabyte board is compatible with my Asus P5Q-EM. 

[AUDIODIDAKT]

Don't worry,

Its already a very good MB, you have there, same specs as the Gigabyte.
But the difference is that this Gigabyte is an OVERCLOCKERS board.
With better power regulation (or power lines), especcialy for that purpose.

I mean you can overclock any motherboard.

PS: and watch out, mini-ATX and ATX !! (it wont fit)
     

[earflappin]

Thanks for the tip!  BTW, on the EMI/RFI front, have you found that using copper foil (as opposed to tin foil...  ) or ERS cloth to help with SQ by suppressing EMI/RFI inside the PC?

[PeterSt]

I found this on-line for $400.

http://www.startech.com/item/PEX2PCIE4L-PCI-Express-to-2-PCI-Full-Length-2-PCIe-Single-lane-Expansion-Box.aspx

I did live chat with them, but they were unable to suggest a supplier for a compatible battery power supply.  Anybody know where I should look for that? 

Thanks!

THIS IS GREAT



Good bye to that Magma stuff which for functionality is the best out there, but this just equals it (did you see the laptop card ?).

If this existed 6 months ago I'll eat some ties.
But about that ... I can't even find it back when going through their products ...

Ok, you can be sure I'll get me one of these and measure noise and everything. Will try some good power supplies as well. You might want to wait for the results.

David, thanks man.

[AUDIODIDAKT]

I think I can see were this leads, haha 

[earflappin]

Glad to put this on your radar screen.  If I send you some poffertjes or matjes will it make your testing go faster?  

I'm going to wait on your findings Peter and in mean time just experiment with reducing internal EMI/RFI and getting a new mobo.