Article: C.A.P.S. v2.0

[Paul R]

Correct me if I am wrong, but my reading of the original description indicated the USB card was there primarily to provide a non-shared USB port for the DAC. <br />

<br />

This is pretty well accepted as a best practice already - on Macs we check to see which port is <i>not</i> being shared with the keyboard, trackball, iSight camera, etc, and use that port/buss for a DAC. <br />

<br />

Actually, the truth is that we check to see which USB buss in the machine is not being used, but that is a bit of a technical nit. The point is, adding in a separate USB card guarantees the DAC does not have to contend with other USB devices. <br />

<br />

Which actually, at least in my experience, does improve the sound, if only because it reduces or eliminates interruptions in the audio stream due to buss contention. <br />

<br />

-Paul<br />

[audiozorro]

For testing purposes and doing A/B comparisons I built two virtually identical music servers except for different Gigabyte motherboards and operating systems (XP Professional and Vista Ultimate 32-bit).<br />

<br />

I expected them to sound identical, but they don't. What's worse is that the Vista music server has problems playing 24/176.4 and higher resolutions without distortions. The XP Professional music server plays all resolutions perfectly.<br />

<br />

So my initial conclusions are that either the different Gigabyte motherboards sound different, or the OS imparts a different sound. The other possibility is that either motherboard in the Vista server or some otherwise identical component in the Vista server has a variation that negatively affects the sound.<br />

<br />

We all know that all products are manufactured to certain tolerances and I am not convinced that low cost components will not sound different if built to specs that have lax tolerances and little or no testing requirements for the fully assembled product.<br />

<br />

So both computers work perfectly as computers and as music servers if playing 24/96 and lower resolutions (perhaps at lower resolutions any real sonic differences are inaudible), but at 24/176.4 or 24/192 the Vista music server is not acceptable. One of these days I will probably just try another motherboard and Win 7 Ultimate to see if the distortion disappears.

[Bob D]

Chris,<br />

I really feel am intrigued by your 2.o design. If possible, I'd like your input and others regarding a few requirements I've thought about.<br />

<br />

HDMI & USB 3.0:<br />

I have need for HDMI and perhaps USB 3.0. I'm thinking about using the ASUS AT5IONTI motherboard which has native USB 3.0 support. http://www.asus.com/Motherboards/Intel_CPU_on_Board/AT5IONTI/<br />

<br />

1) Do you think connecting USB 3.0 External Drives (used for flac file storage and retrival) would be an issue as it pertains to server performance of any kind? If so, how so?<br />

2) Do you think using a SOtM power supply filter on the external USB drives would be of value even though I can/would comment them into my PS Audio Premier Power Plant?<br />

3) How did you install the SOtM Power Supply Filter in the M10 case?<br />

4) Is anyone aware of other alternatives to consider for motherboards that would meet the HDMI need and have USB 3.0?

[internethandle]

I'm a bit confused as to why you're dismissive of ADuM4160-based USB isolators due to their speed limitations. I've never seen this objection brought up elsewhere in discussions of said isolators (on head-fi, Computer Audio Asylum, etc.), and it was my understanding that most USB DACs don't require anything in terms of signal speed above what ADuM4160 isolators like Circuits@Home's or Olimex's can provide. Am I wrong? Granted, my particular USB DAC is not asynchronous (or adaptive, for that manner), so maybe that's where the issue lies, or maybe I'm not aware of some SQ improvement that "full-speed" USB 2.0 can provide for USB DACs of all varieties.<br />

<br />

I also had an unrelated question for anyone re: the SATA noise filter by SoTM - is this a PCI-based device as well, or if not, how would one go about mounting it in a given PC case?

[1audio]

The ADI isolator chip handles up to 12 Mbps. Fast enough for 24/96 but not enough for 24/192 (its just shy of the requirements for 24/176). The firmware won't support the data rate unless the system can run at "high speed", and the ADI chip won't run at high speed. <br />

<br />

The SoTM SATA filter plugs into the back of the drive and the data and power cables connect to the filter. It doesn't go near a PCI or PCIe interface.

[Bob D]

Noel, <br />

<br />

Thanks for the response. As I stated the big driver for me in using the Asus board is the HDMI and native USB 3.0. I think swapping it for Chris' design makes sense for me unless I'm missing something. I've read on the ASUS site the board is particular about memory brand. I need only 1 PCIe slot for a firewire card since I'm using the Weiss DAC202. <br />

<br />

I did have a question for anyone regarding the use of External USB drives for flac file storage. I don't think retrieving file from a NAS via ethernet vs a attached but external USB drive should matter. Do you?

[jacobacci]

Great article, Chris, thanks a million. This site continues to be a great source of insights.<br />

Since a few months the AMD Fusion 'Zacate' motherboards have been on the market. While the ITX boards don't offer Firewire, the ASUS mATX variant does (e.g. http://www.avsforum.com/avs-vb/showthread.php?t=1313541). They all have full HD capable HDMI.<br />

The Zacate boards were probably out a bit too late for CAPS V2, but they could potentially be very suitable for firewire (e.g. Weiss) systems, as a separate firewire card is not needed. VIA firewire chipsets are listed as compatible with the Weiss interface.<br />

Have you looked at Zacate boards?<br />

Does anyone else have any views?

[johniboy]

i still like this one more. at least for systems (like mine) that require a soundcard for spdif out. <br />

<br />

http://www.ichbinleise.de/Media-PCs/ichbinleise-HFX-M27-Intel-luefterlos::3801.html<br />

<br />

it is more powerful than the atom based systems (much more powerful), has hdmi out for video (if required), a board with a very good power management, no moving parts, an external power brick with which delivers sufficient and clean power, PCI slots, ssd, network and so on. it might be possible to tweak this a bit more but i think it delivers 90% max performance out of the box.

[89reksal]

Hello,<br />

I live in Canada and have been unable to find a Canadian supplier for the spec'd Jetway motherboard. Ordering anything from US adds considerable expense. In looking at alternate possibilities I came across this board which based on my limited knowledge looks like a viable replacement at less than half the price: Intel D525MW Mini-ITX Motherboard<br />

<br />

Here's a link to a review:<br />

<br />

http://www.missingremote.com/review/intel-d525mw-mini-itx-motherboard<br />

<br />

I've added this link as well which is a comparison of this board and the spec'd Jetway:<br />

<br />

http://compare.logicsupply.com/matrix/?id=90&id=78&id=92&component=mainboard<br />

<br />

I'd be very interested in hearing any thoughts on using this as a replacement. Thanks in advance.<br />

<br />

Bill<br />

[The Computer Audiophile]

Hi Guys - Thanks for the great number of responses both positive and negative. I'm happy people are talking about version 2.0. I wanted to wait a bit before responding as some of the questions just seem to flesh themselves out on their own. First a few thoughts then some responses to direct questions and comments.<br />

<br />

In general this is not a movie or video player. It's an audio only build.<br />

<br />

I'm not really going to comment on other boards now other than to say I looked at all of them and even contacted manufacturers about boards not released while designing version 2.0. Most other boards that appear to meet the CAPS requirements actually don't because they require a full blown power supply, different case, and can quickly lead to fans etc…<br />

<br />

 <br />

<br />

Eloise - <i>However, I would argue that if you did this then your machine would not be a CAPSv2 machine... CAPS v2 is a complete recipe set down by Chris that he has found makes a great machine (for USB or FireWire DACs). Anything else is just an Atom based computer custom built to your own specifications. Nothing wrong with that, just it's something else! … While it's great to discuss alternative recipes for servers; remember anything outside of Chris's suggested items is no longer a CAPSv2 server.</i><br />

<br />

Thanks Eloise well said :~)<br />

<br />

 <br />

<br />

quest - <i>3. You don't have to copy Chris's build entirely. I don't think many readers have experience with things like the USB card to be able to quantify the difference (I'm trying to fit one in though I do not have PCI), so just go with what you feel is right. Either way am sure if you follow general guidelines you will get 90% of the way there.</i><br />

<br />

Thanks quest well said :~) Discussions about other builds are more than welcome in other threads.<br />

<br />

 <br />

<br />

Eli - <i>Can you pls share with us the JRMark of the CAPS 2 ?</i><br />

<br />

Score = 471 with 50,000 tracks and all storage on a NAS.<br />

<br />

 <br />

<br />

Dan Hackley - <br />

<i>1. Is there a GPU built into the motherboard? Will this be powerful enough to render covers etc in JRiver? The reason I ask is that when I browse covers in JRiver (Sony Vaio laptop) in the "cover wall" mode it's a bit slow and jerky when rendering all of the covers.</i><br />

<br />

Version 2.0 has no problems at all rendering covers. I know what you mean when talking about version 1.0 and its jerky response in this area.<br />

<br />

<i>2. What are the video-out options? I have a 24" TFT monitor at a resolution of 1920 x 1200 ; would the CAPS be fine with this? The Vaio's output to the monitor is slightly blurred for some reason.</i><br />

<br />

I think you'd be pushing it with the analog VGA output on version 2.0. No other video out options without an add-on unit.<br />

<br />

<i>3. Is this wifi-enabled? I use an iPad as a remote control, and JRiver would have to be able to utilise its DLNA server & renderer abilities to allow this.</i><br />

<br />

No. A WiFi card can be placed in the mini-PCIe slot on the motherboard if needed. I simply connect the server to my Gigabit network that all my wireless devices access as well.<br />

<br />

 <br />

<br />

Audiozorro - <br />

<i>1. Mitigating the sonic problems with USB in the computer require a $331 solution whereas firewire has no similar sonic problems and an $8 card is all that is necessary.</i><br />

<br />

If I knew of a FireWire card that worked with DACs like the DAC202 and was built to the specs of the SOtM I would have tested it in this build. I think it's a giant stretch to suggest FireWire has no similar problems.<br />

<br />

<i>2. The USB ports built-in any and all computers are sonically compromised and require something like the SOtM tX-USB and SOtM In-Line SATA Power Noise Filter in order to achieve the ultimate in sonics.</i><br />

<br />

For the most part yes. Computers built to the lowest price using commodity parts so the Housewives of Orange County can shop online and print photos aren't as good. Manufacturers can't cost justify anything else. Ask Gordon Rankin about his experience designing motherboards etc… He had bean counters over his shoulder constantly cutting back his designs to meet price points.<br />

<br />

<i>3. While USB to SPDIF solutions may do an excellent job in mitigating the sonic problems inherent in SPDIF and allow legacy DACs to be used, the best solution will generally be using something like the SOtM tX-USB and SOtM In-Line SATA Power Noise Filter in any computer with an excellent USB DAC.</i><br />

<br />

There is no single best solution for all systems.<br />

<br />

<br />

<i>4. How any of the above fits in with the upcoming Auralitti (sic) L1000 File Player which claims AES/EBU output for best low noise interface to DAC or would the L1000 be sonically superior with USB or firewire?</i><br />

<br />

Again, there is no best solution for all systems.<br />

<br />

 <br />

<br />

jrobbins50 - <i>In CAPS1, I've been successfully using the ASUS Xonar Essence ST audio card. Is this incompatible with CAPS2?</i><br />

<br />

Not without a different case.<br />

<br />

<br />

<i>CAPS2, it would seem, is a more audio purist version</i><br />

<br />

Yes.<br />

<br />

 <br />

<br />

spright - <i>What changes if any are you running within J River now that you're outputting with USB?</i><br />

<br />

I'll detail my J River setup in a follow up email with screenshots etc… Thanks for asking.<br />

<br />

 <br />

<br />

lasker98 - <i>First off, is USB sound out as implemented in CAPS2 "better" sonically then what would obtained from using digital out from a sound card such as the Juli@, Lynx or ASUS Sonar Essence?</i><br />

<br />

In my system yes.<br />

<br />

<i>If yes, would it be worth while for me to use the CAPS 2 as spec'd, and then use a USB to S/PDIF converter such as the Halide Bridge to feed my dac digital input?</i><br />

<br />

I would go this route in my system, but that's not your system.<br />

<br />

 <br />

<br />

ecwl - <i>I almost got a feeling that Chris is implicitly saying that in the CAPS v2 server, on his system, the SOtM tX-USB + Wavelink sound better than Lynx AES16.</i><br />

<br />

I tried to be very explicit about this in the article :~)<br />

"The most critical improvement to v2.0 is the replacement of the Lynx AES16 with the SOtM tX-USB card."<br />

"The performance and sonic quality of Pocket Server 2.0 has truly surprised me. I believe the Computer Audiophile Pocket Server version 2.0 is better than version 1.0 in every respect. Yes, that unequivocally means sound quality. Period."<br />

<br />

 <br />

<br />

bob - <i>I'd be utterly astonished if a USB add-in card made a difference to the quality of sound coming out of any sort of USB dac. If it does, then the likely answer is that the dac manufacturer needs to go back to the drawing board!</i><br />

<br />

There is so much more than goes into DAC design than meets the eye. Supplying a cleaner signal to a DAC doesn't say anything for how a DAC is or should be designed.<br />

<br />

<i>If there is a technical justification for such a card, then every existing USB equipped audio device has just been rendered inadequate.</i><br />

<br />

I can't think of a single reason any DAC would be rendered inadequate because of improvements to a transport. If anything improvements to a transport should give DACs a longer life span. A better source doesn't invalidate a product further down stream.<br />

<br />

<br />

<br />

<br />

<br />

<br />

[BobH]

....."There is so much more (that) goes into DAC design than meets the eye"<br />

<br />

As I said, the signal specification is quite clear. If it is so very 'dirty' as to justify an 'audiophile' clean up job in the computer, then I would expect the designer of my audiophile dac to build said clean up circuity into my dac. <br />

<br />

....."I can't think of a single reason any DAC would be rendered inadequate because of improvements to a transport."<br />

<br />

I can. Because to accept that an audiophile usb card is justified is to accept that dac manufacturers have not paid enough attention to the usb inputs of their products.<br />

<br />

A quick perusal of Ayre Acoustics white paper, written to support the release of their QB-9 dac, would certainly seem to indicate that they gave the subject much thought - as indeed they should.<br />

<br />

What you are effectively saying is that their dac will perform better from a server equipped with the SoTM card, than it will from a standard computer. If this is true then the input circuitry in the QB-9 is, by definition, not as good as it could be. I would imagine Ayre, Naim, dCS, et al, are all very interested in this new learning! <br />

<br />

The Ayre white paper states quite clearly how they have completely isolated the usb receiver section, using high speed opto-isolators. If it is, indeed, completely isolated, then how is cleaning up the signal first going to help?<br />

<br />

I'm sorry, but audiophile usb cards deserve the same credibility as audiophile network cables and tube motherboards - there is simply no technical explanation that justifies them. Give the money to charity.

[firedog]

Really interested by this Chris. <br />

<br />

I already own a fanless server, so I think I may order the SATA noise filter and see if I hear a difference. Sounds like an inexpensive way to improve quality of power in a music system.<br />

<br />

The USB card is also interesting, but I'm still using a Squeezebox system, so I don't need it. But in the future, if I want USB, it would definitely be a consideration.

[The Computer Audiophile]

<i>"What you are effectively saying is that their dac will perform better from a server equipped with the SoTM card, than it will from a standard computer. If this is true then the input circuitry in the QB-9 is, by definition, not as good as it could be. I would imagine Ayre, Naim, dCS, et al, are all very interested in this new learning!"</i><br />

<br />

<br />

I think everyone at Ayre would happily admit the QB-9 is not as good as it could be. Given an unlimited budget the QBQ-9 and most other products can be improved. Interesting you mention Naim. It highly recommends using Toslink into its components because of what it believes are issues with dirty USB connections. Many manufacturers are on their first or second DAC with a USB input compared to many DACs with the long-used S/PDIF interfaces. I don't think anyone has taken the USB interface as far as it can be taken on any front. In addition there's no free lunch. Every step taken to clean something up after the fact can have negative consequences down the road. <br />

<br />

Your statements make it seem like there is no connection between the internal components of a DAC and the computer. There is most definitely an electrical connection otherwise many of the USB chips inside DACs wouldn't function. Many require power from the USB bus even though they are powered by other means elsewhere in the unit. In addition to power there's a great advantage to separating the USB DAC on its own "private USB bus" for lack of a better term. Hence my MacBoo Pro example.<br />

<br />

It really seems like you're saying that you've mastered everything there is to know about USB audio and the different forms of USB communication. That's quite a bit more than everyone I know including the leading USB DAC engineers. <br />

<br />

I'm not out to get you Bob. A good constructive conversation is always beneficial. I just feel very strongly about these products. We merely disagree on this one and maybe other items as well. Who knows? I really hope you have a chance to listen to the SOtM products.<br />

<br />

<br />

[EuroChamp]

Hello Chris!<br />

<br />

Well done!!! I enjoyed reading the article of CAPS1 and now of CAPS2. I think, almost everyone can get new informations in building an audio computer - or can build exactly this C.A.P.S. v2.0.<br />

<br />

PC and Microsoft and network and firewalls are my business and in my opinion I would not disable the windows firewall and at the same time not install antivirus software. As a compromise I would have the firewall running, opening only the really necessary ports: RDP or VNC, filesharing and the JRMC Ports. Then "never" browse the web, never use IE, Firefox, Chrome, ...<br />

And finally I would not install any av software.<br />

In my opinion this is a good practice in the case you want to run the server for some years und never worry.<br />

"AUDIO PC IS NOT FOR INTERNET SURFING - NEVER"<br />

<br />

In all other points i agree to you :-)<br />

<br />

And finally:<br />

Have you ever compared mainboards with these small 12V psu's against the other ones with ATX power connectors?<br />

I'm using this fanless example - but I've never compared to your solution.<br />

http://www.seasonicusa.com/NEW_X-series_Fanless.htm<br />

<br />

Enjoy listening,<br />

Bernhard

[BobH]

Chris - thank you for responding <br />

<br />

I'm certainly not trying to claim I know everything, as I'm sure neither are you. It would be fair to say that, with regard to the technical need for boutique audiophile computer components, I am firmly unconvinced by anything I have so far either read or heard.<br />

<br />

My real point here is that the place to cure any 'ills' of the usb bus is in the dac, not in the computer. Computers, both physically and in specification, are changed and updated regularly, for all sorts of reasons. An individual's 'high-end' dac is not. <br />

<br />

The usb specification dictates a minimum acceptable performance. This gives a dac designer a known minimum level - if the dac is designed to this level then it will perform as it should regardless of the computer it is attached to. That seems, to me, to be the correct approach to the 'problem'.

[The Computer Audiophile]

Hi Bob - Thanks for the response.

[The Computer Audiophile]

Hi Bernhard - Thanks for commenting. I did look at the Seasonic PSUs very seriously. However, due to the size and heat dissipation I opted for other components. Granted the heat dissipation isn't too bad it's still nothing near an external PSU like I selected. <br />

<br />

If I were to build a larger server using something like the Corsair 600T I would certainly use the Seasonic PSU.<br />

<br />

Thanks again for posting :~)<br />

<br />

[SKoo]

Wow, great post! I've been looking forward to this for months. Really amazing how the CAPS has stirred things up, and how many people are posting back. I'm definitely going to give it a try, once I finished the speakers I'm currently working on, and will get back with the result.

[SBright]

Hi Chris et al,<br />

<br />

So is the wavelink or equivalent a required part of the CAPS v2.0 picture? If this is the case shouldn't it be listed as an item? If so, this makes CAPS v2.0 considerably more expensive and on par with some of the more expensive music servers.<br />

<br />

In CAPS v1.0 you detail the external cables that you tested. Can you please elaborate on this for this version?<br />

<br />

Out of curiousity which DACs are you testingrunning it with?<br />

<br />

Thanks<br />

<br />

SBright

[The Computer Audiophile]

Hi SBright - The WaveLink or similar is not required. I'm also using version 2.0 with the dCS Debussy, Audio Research DAC8, and Meitner MA1 all via USB directly. Numerous cables are in use, none of which are part of this version 2.0 formula. <br />

<br />

As I said in the article I'm not looking to compete with any manufacturer or current products. If the price of version 2.0 is <I>"on par with some of the more expensive music servers"</I> then so be it. C.A.P.S. has traditionally been for readers looking to build something on their own. <br />

<br />

[SBright]

Thanks for the additional details, much appreciated.

[Quest]

Just to add on to Chris's comments, I personally am using the Seasonic X series. You'd need a larger chassis like what I am using (hfx classic) to ensure adequate airflow. With a large fanless casing like that, even with higher loads, my PC rarely hits above 40 degs.<br />

<br />

The ripple rates and other specs for them are very good so I'd still keep them within consideration if they could be accomodated.<br />

<br />

Like Chris, I also evaluated other options such as external psu but did not do so just because of additional cabling which I felt was not so great for the PC, even though I could go for a good linear PSU.

[extracampine]

Thanks Chris for helpfully answering my questions!<br />

<br />

You said the JRMark in Jriver was 471. Isn't this quite a low score? <br />

<br />

According to the JRiver site:<br />

<br />

STANDINGS:<br />

Best: glynor JRMark (version 14.0.83): 2867<br />

Worst: rick.ca JRMark (version 14.0.83): 264<br />

<br />

Dan

[Quest]

What does this JRMark tell us?<br />

My fanless PC scored 2578.

[The Computer Audiophile]

Here's a snippet from the J River site about JRMarks. <br />

<br />

http://yabb.jriver.com/interact/index.php?topic=54396.0<br />

<br />

"Matt added a Benchmark program in build 83 that measures overall system performance. It gives you a way to compare machines. It also gives us a way to measure changes in the code and look for new ways to enhance performance.<br />

<br />

Your results will change over time for several reasons:<br />

<br />

1. A faster machine -- overclocking, for example<br />

2. A newer version of MC with performance improvements<br />

3. Power settings of the machine<br />

4. Other programs running<br />

<br />

STANDINGS:<br />

Best: glynor JRMark (version 14.0.83): 2867<br />

Worst: rick.ca JRMark (version 14.0.83): 264"