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

[AUDIODIDAKT]

Peter,

Can this be your PC to DAC connection ??

DVI ?

[Per]

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.

Thanks, Earflappin. I live in Denmark - on the beautiful Island of Bornholm http://bornholm.info/?langId=2 just south of Sweden and actually it belonged to Sweden once so you were very close with your guess 

I.e. is it okay for the cards to be powered up and down separately from the mother board?

Well, to be honest I do not know. But I guess so.

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

I don't know right out from memory of any finished SLA battey based powersupply product besides UPS powersupply's for PC's that some audiophiles use, but a while ago - on a rare day where I felt a little better - I just connected my TEC 7510 DAC to a standard 7.2 aH SLA battery that my wife boutght me (They are very heavy stuff these lead batteries said my ahcing muscles Well, I cut the power supply cord from the DACs cheap standard switchmode powersupply and connected the wires (remember right polarity!) to the poles of the battery. I then just put back the small plastic protector connectorcaps on the battery poles - and voila,  up and running I was with a drastically improved sound quality.

I have read that it is advisable to ALWAYS put an inline fuse of for instance 1A on the positive lead from the battery to prevent any disasters. (Remember a 12 volts SLA battery of 7.2 aH is VERY powerful and full of hazardous metarials). Enjoying the sound quality (every aspect improved) I unfortunately forgot to monitor the voltage on my SLA battery and when the sound from my DAC started dying and distorting terribly it was also too late to save the battery  Voltage had dropped to (well, errm, to below 6 volts) I was not able to recharge / revive the battery.... 

Regarding sound quality and different brands of SLA batteries, Yeo from www.diyparadise.com has strongly advocated for Hitachi as the premium choice for sound quality. On another line one could also experiment using Li-Ion batteries or the newer Li-Iron types. I think Wavelength Proton (from Gordon Ranklin) has some kind of semibattery psu design based on an internal Li-Ion battery. From what I have read battery power always fare very well against quality linear / switchmode psu's even though the output resistance from a top quality psu is much lower (around 0.1 hom or so I think) Output resistance is - I have read - important for minimal noise and sound quality. But using a battery hooked up the way I did is definately more difficult to handle than an ordinary plug and play psu...

Hope all this was not to way off-topic. Praise to Peter for his very kind and forgiving attitude

Per

[mojave]

I purchased some ERS cloth a few years ago after it was recommended in a thread a head-fi.org. However, it disappeared (I think it was thrown away by my mother-in-law) before I ever installed it. I might purchase some more for my new computer build.

Regarding motherboards and power phases, I have wondered how the power phases effect sound quality. I sent an e-mail to Anand at anandtech.com inquiring about the power delivery circuits in motherboards. Here is what I wrote:  "I enjoyed reading your article today on the new processors and P55 motherboards. I also read your recent article called, “How Much Does it Cost to Build a P55 Motherboard?” One of the main things that set the various motherboards apart was their power delivery circuits. It would be nice to have an article about a motherboard’s power delivery circuit, how they vary, benefits of more phases, and how these circuits affect sound quality in an audiophile HTPC. Thanks." I didn't get a reply, but maybe he is working on the article. 

I have been researching PC power supplies and found that the Corsair HX850 and the Antec Signature 850 have the lowest ripple and are among the most efficient power supplies, even at lower power usage. They are also almost silent - especially when providing the lower amount of watts needed for a typical HTPC.

I am also planning to purchase the Asus Essence ST soundcard as soon as it is released in the U.S. It has an EMI/RFI shield over the analog section and a "copper “faraday” barrier that isolates the power conditioning circuitry from the sensitive analog amplifications circuits." Furthermore, the analog section has its own molex power connector for receiving power directly from the power supply without any noise being introduced by the motherboard, etc.

I talked to Gary Dodd of Dodd Audio at RMAF. He is one of the leading edge designers of battery powered tube preamps and tube amplifiers. He said he could build a lithium ion power supply for the Essence ST soundcard that would have no noise whatsoever. I haven't talked to him since, but when I get the card, I may consider going that route.

In anticipation of the Essence ST, I have already purchased some opamps to replace the stock units. I have also purchased a 1ppm TCXO to replace the stock clock on the soundcard. 

[earflappin]

Mojave, thanks for your excellent post!  I will want to track your progress on the Asus ST card - it sounds like they are going the extra mile to ensure optimal SQ.  I really like the ability to bypass the mobo for power input.  Likewise, I like the idea of a Dodd power supply for that card.  This approach is very much in line with where my thoughts were headed, although I still like the idea of getting the card out of the computer chassis using the StarTech PCI expansion chassis.  Taking this approach makes it so easy to use the card for other computers.

Thanks again!

[GerardA]

Very interesting topic!
Now I wonder if a spdif/connection from a soundcard to an external DAC would be better sounding then using the SPDIF-connector on the motherboard. The latter goes through the northbridge, southbridge and a Realtek-codec (ALC889A),
while the former goes through northbridge pci-expres and soundcard.
Any idea's/experiences?

I agree with audiodidact on the Gigabyteboards. My ma78gpm-ds2h has:
- lower RDS mosfet, ferrite core chokes and lower ESR Solid Capacitors! Sounds like good marketing talk but also sounded better then the regular version. (And what about Intel vs AMD?)

And for the battery, I once used a pc-powersupply to feed my preamp because the battery broke down. Never heard such an awfull sound. Back to battery and overnight charging!

[AUDIODIDAKT]

Very interesting topic!
Now I wonder if a spdif/connection from a soundcard to an external DAC would be better sounding then using the SPDIF-connector on the motherboard. The latter goes through the northbridge, southbridge and a Realtek-codec (ALC889A),
while the former goes through northbridge pci-expres and soundcard.
Any idea's/experiences?

I have the Juli@ for that purpose only,
Maybe the Asus Essence will be a better choice, now a days.

I have tried the onboard ones on both Gigabytes boards and they sound horrible.
I have expressed this before, I believe.

[GerardA]

Thanks for repeating Roy!
Then there is still room for improvement. Juli@ is the best for SPDIF?
BTW. What codecs did your Gigabyte have? Azalia HD or the old AC97?
I saw the Juliet is PCI and thus goes through north and southbridge.
I would prefer therefor a PCI-e solution. Especially because that's the only slot left available in my HTPC!
Maybe Asus or Maya?

[Gerard]

Maybe the Asus Essence will be a better choice, now a days.

Hey Audiodidakt,

I have read something about the card.

http://www.hardwarecanucks.com/forum/hardware-canucks-reviews/11709-exclusive-asus-xonar-essence-stx-sneak-peak.html

This is what i have read.

There is also an S/PDIF digital output featuring optical and coaxial output of Dolby Digital Live for those who want or need full surround sound. Make no mistake though, this card is designed to be an analog powerhouse above all else.


What do they mean by this... Meaning is this a normal SPDIF output?

Grtz Gerard 

[AUDIODIDAKT]

First of all the Asus best part is the analog part.
But we are not interested in that, I dont.
I want spdif to dac for now (until NOS1 comes available)
But maybe some people like it for its analog achievements

I think maybe this card can do better than the Juli@ or others in this league. (or because maybe you can fiddle around with power supplies on STX)
I like the juli@ very much for know, still awaiting that better solution.

The Juli@ is quite cheap compared to the Asus Essence STX.
Only the juli@ needs tweaking output for decent COAX spdif connection.
I did expressed this too before.
I was somewere in here.
http://www.phasure.com/index.php?topic=967.msg7816#msg7816

Don't want to spend too much on different cards and such, rather save up some $ for the NOS1.

[AUDIODIDAKT]

Then there is still room for improvement. Juli@ is the best for SPDIF?
BTW. What codecs did your Gigabyte have? Azalia HD or the old AC97?

Azalia HD that is!
Are you using the onboard one ?
Then I am really curious what a rather good souncard can do for you.
I would say get a Juli@, you can hold solder-iron a make yourself a decent COAX SPdif.
But you prefer a PCIe, then I don't know accually, Maya or STX

[GerardA]

Hi Roy,

I checked the juliet and it seems to have the same Envy24HT that my Terratec Phase 24FW has.
The onboard SPDIF sounds definitly better then the Terratec's.
One way it also depends on what it is that makes the SPDIF sound better/worse.
I hoped to find a more technical answer to this because just buying something to find out myself is not the way I work...
And of course what is the DAC doing to get the SPDIF-signal tick?
BTW, can you describe the improvement you heard?

[Fidelio]

First of all the Asus best part is the analog part.

You should hear the Onkyo card then...propped full of Black Gates by the way

Its toslink output sounds great as well, but obviously the whole point of the card is ist analogue part.

[AUDIODIDAKT]

Maybe we went a bit

maybe its better to put this in another topic (or existing one)

haha

and keep this one alive!!

[ed linssen]

Hi Gerard,

The ASUS card is meant to be used through its analog outputs. By tossing the opamps you can modify its sound to your own taste if you think you should do so! The same with the opamp of the headphone-amp. The link of the card you name is about the Essence STX. The latest and the most interesting card is the Xonar Essence ST. So without the X! The STX is a pci-e card while the ST is the classic pci. It is a better way because it doesnot need the pci-e to pci conversion. Besides Asus claims to use a specially developped circuit to bring down RFI to a lower level. In the ST. which is intoduced in europe round Juli. (STX earlier in the year round Jan) Maybe the ST is not yet on the shelves in the US.
Btw. the ADconverter is NOT the Cirrus Logic cs5361, but it's better brother the CS 5381. So analog recording is in good hands too.

I must say the thing sounds really good in its stock outfit. Its up to you!
I myself changed my complete powersupply for for a big 60amps battery. The best way is to bring in the and 12Volts seperately on the Molex-plug. However there still was an SQ improvement by feeding the whole computer with the battery. Only my cumputer including the card draws about 2 3/4Amps!. I just use a two-position powerswitch which switches the powerline between off/charging and not charging/on. So I can play about the hole day uninterrupted if I like, and charge overnight with a little automatic 2,5Amps wallwartcharger.
Watch out that the voltage of the battery doesn't drop under the 11,2 Volts or so. Doede Douma (dddac.de) has a very simple device to control this.

Fun,

Ed

[PeterSt]

Maybe we went a bit

I think it is okay. If David thinks it is not, he will say so, I'm sure.

In the end the subject is always the same : how to get the sound out of the PC the best way.

Maybe I was the first crazy back in 2005 to buy a Fireface800 to do it the best way thinkable back then, but today I'm using a PCI card just the same because net it works out the best. This doesn't mean it is the most optimal, and for a longer time I indeed thought about the PCI extenders. This is just theory though, but already 20 times more practice when it is affordable to begin with (thinking commercial here ).