• C.A.P.S. v2.0

    Early in 2010 the original Computer Audiophile Pocket Server design was published on CA. At the time I wasn't sure if readers would be interested in building their own servers. I thought it would be a great thing if many computer audiophiles used the exact same music server. This could ease troubleshooting and enable the sharing of successful tweaks among all C.A.P.S. users. I had no idea the C.A.P.S. server would become incredibly popular among computer audiophiles. Many CA readers commented on the original build with suggestions to make it better while others were delighted someone else had done all the work. I was very happy to read both types of comments. After the original Pocket Server debuted I began fielding questions about it at every computer audio seminar I attended. A few months later in true computer audiophile fashion everyone was asking about the next C.A.P.S. server. The inquiries were a double-edged sword. I was thrilled so many people expressed interest in the server. At the same time pressure was building to create something better. After nearly 18 months I believe I have something better. It is with great pleasure that I reveal the Computer Audiophile Pocket Server version 2.0!




     

    C.A.P.S. Version 2.0

    I was originally going to release version 1.5 as a minor update to the first Pocket Server. I was underwhelmed by some of the "upgrades" available from computer component manufacturers and couldn't justify calling it version 2.0. However, I have since scrapped the design of v1.5, wiped the slate clean, and built new version 2.0. This is not a minor upgrade to version 1.0link. I have tentative plans for version 3.0 but readers should not hold their breath waiting for this version. The current plan is very different, complicated, and will need a new set of requirements. Thus, if you like v2.0 don't wait for v3.0 as you might be disappointed and waiting quite awhile.

    My goal in publishing C.A.P.S. v2.0 is the same as it was for the original Pocket Server, "[T]o put together a hardware and software music server solution that I would actually use and the Computer Audiophile readers could actually use. I would do the leg work, test & listen to everything, and provide the information for CA readers to put together the exact same music server."

    Readers unfamiliar with history behind these servers are likely asking why the name Pocket Server? Here is a brief explanation copied from a comment response to version 1.0. "The title does not reference the literal size of the music server. The name Pocket Server is no less accurate than the name Compact Car…Along the way this server was named the Pocket Server by a colleague who was very surprise at its small size when I pulled it out of my carry-on luggage. The server is a bit larger today than it was at that time but the name hasn't changed. This colleague named the server because it was so small not because it actually fits into a pocket. I elected to keep the name, going with the spirit of the name not the letter of the name."

    Many CA readers realize standard off-the-shelf computers don't make the best high-end audio music servers. Sure a regular Dell built with nothing but price in mind, with commodity parts and software from any company willing to fork over enough cash, can work as a music server. Such a computer is usually good as a proof of concept machine but literally nothing else that has to do with high-end audio. Don't believe me? Try it and report back in the comments section below. The prevalence of USB DACs in high-end audio has made the need for a quality computer even greater. A quick glance at most computers built today usually reveals a few internal USB hubs to which devices like IR receivers, Bluetooth controllers, keyboards, trackpads, memory card readers, and built-in cameras are all attached. Most users have no clue computer are built this way. Computer audiophiles frequently avoid using external USB hubs like the plague. Little do they know they're using internal USB hubs for their USB DACs. Evidence of one problem related to this can be found by using a USB DAC with a pre unibody MacBook Pro. If the DAC is not connected to the correct USB port the listener will experience audio drop-outs. The trouble stems from several internal devices sharing the same USB bus, namely the keyboard in this situation. In layman's terms there are too many cars on the highway. The audio car should be in the dedicated high occupancy vehicle lane cruising by itself. In reality this is rarely the case.

    Throughout the history of consumer electronics the massive mainstream consumer base selects a technology because of its convenience. The niche high-end audio industry perfects this frequently less than desirable technology. Think optical S/PDIF - TosLink. Audiophiles are always striving to improv technology whether it be turntables, CD players, or music servers. The C.A.P.S. v2.0 design is no exception. This is a USB based design that's unlike almost every other music server. C.A.P.S. v2.0 addresses potential USB issues by providing the USB audio data its own autobahn in addition to other leading edge customizations. 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.

     

    Requirements

    The requirements for version 2.0 are identical to the original Pocket Server. The requirements are both objective and subjective. When necessary I'll do my best to explain how or why my component selections meet these criteria.


    1. Absolutely silent.

    2. Capable of great sound.

    3. Great looking.

    4. No moving parts.

    5. Fairly inexpensive.

    6. No legacy components.

    7. Easy to operate.

      1. Directly or

      2. Remotely



    8. Easy to assemble / install

      1. Assembly / installation by one's self or

      2. Assembly / installation by local computer shop, son, daughter, neighbor, or friend.



    9. Small size.

    10. Low power consumption.

    11. Low heat.

    12. Accept an add-in card for audio or additional capabilities. Hardware & Software must accept appropriate add-in cards.

    13. Play 16/44.1, 24/44.1, 24/88.2, 24/96, 24/176.4, and 24/192 all bit perfect.



     

    Hardware

    Motherboard
    The main component of every computer is the motherboard. Selecting the right one is the toughest part of designing a server. It's very easy to go overboard with features and wind up with a board that requires so much cooling it sounds like the Space Shuttle. On the the end of the continuum are the boards without any features. These low power featureless boards are interesting but not for a C.A.P.S. design. My motherboard selection for C.A.P.S. v2.0 is the $167 Jetway NF96FL-525-LF. One thing to note about this board is its large heat sink. There is no way to use a full height PCI card, even with a riser, without hitting the heat sink. The main features of this board are a dual core 1.8 GHz Intel Atom D525 fanless processor, capacity for four GB of RAM, Integrated graphics, PCI slot for expansion, an eSATA port, and built-in DC 12-volt power. The dual core 64-bit Atom processor is a major improvement over the original server design. C.A.P.S. v1 was very close to maxing its slower single core 32-bit Atom processor. Like the previous design this processor requires no fan to assist in dispersing heat and satisfies the no moving parts, absolutely silent, low power, and low heat criteria. The other critical component for a silent fanless design is built-in DC power. This enables use of a small external power supply that connects to the rear of the server. Finding a "regular" fanless power supply is not impossible but can severely limit one's case options due to size and heat dissipation. The Jetway's support of 4Gb of memory is another major improvement. Mainstream operating systems and applications continue to take "advantage" of more memory every release. The eSATA port on this motherboard was one of the features that elevated this board over all others. I realize not every computer audiophile has or wants a Network Attached Storage (NAS) device. These users require direct attached storage. It has been my experience that the speed of eSATA disks is a great benefit to music servers. The annoyance of waiting for an external hard drive, even if it's only a second or two, can drive users nuts over time. Using eSATA this annoyance should be reduced considerably. The remaining feature that is imperative to the C.A.P.S. v2.0 design is the PCI expansion slot. The PCI slot may seem like old technology when compared to new blazing fast PCI-express slots. However, many PCI-express cards such as the Lynx AES16e are actually bridged PCI cards made to work in PCI-express slots. The advantage of PCI-express may be moot for most music servers. Plus, C.A.P.S. v2 requires a PCI slot for its superior USB implementation discussed elsewhere.
           


     

    Ancillary Components
    The remaining ancillary components aren't as exciting but required nonetheless. The memory used for version 2.0 is 2x2GB (4Gb total) modules of DDR2 667 from Transcend. The motherboard front side bus runs at 667 as well. The fact that this memory is standard size as opposed to "laptop" size memory is a plus. It should be easier to find other options and cost less than the smaller modules. There were a few options when selecting the power supply for this C.A.P.S. server. I ruled out using a linear supply for many reasons such as cost, size, complexity, scarcity, and logicality given the standard onboard switching power supplies. The three main PSU options were either 60, 80, or 102 Watts. This server is not power hungry so I followed the less is more path by selecting the Casetronic PW-12V5A-L5 60w supply. The solid state drive selected for version 2.0 will probably surprise many readers. I usually select OCZ drives as they are my standard go-to SSDs. This time I selected the very inexpensive $100 64GB Micro Center brand drive. The Micro Center drives are manufactured by ADATA using the SandForce 1222 Controller. I've used this very good performing drive over the last few months without any issues.
           


    The one piece of C.A.P.S. v2.0 that remains unchanged from v1.0 is the $320 Origenae M10 computer case. I simply haven't found a better case for the job that meets all the requirements. The M10 is great looking, small, and is compatible with PCI add-in cards. There are literally hundreds of computer cases available that could have been used for this design. Unfortunately almost all of them are hideous looking compared to the M10. The Origenae M10 has form and function.
           

     


     

    Audiophile Add-ins
    The next two pieces of the C.A.P.S. v2.0 puzzle will never be found in an off-the-shelf Dell, HP, Apple, etc. The SOtM tX-USB and SOtM In-Line SATA Power Noise Filter are as far removed from standard commodity computer hardware as it gets. The inline SATA noise filter connects directly to a hard drive whether it's solid state or standard spinning disk. Regular SATA data and SATA power cables are then connected to the filter. No special cables required. The installation could not be simpler. The SOtM filter has individual 12V, 5V, and 3.3V RF noise filters in addition to ripple noise filters. I was skeptical at first but after seeing objective measurements detailing the positive effect this filter has on a computer system and placing this filter in the new C.A.P.S. server I'm sold. Add to cart for all my servers. The SOtM tX-USB is a half height PCI to USB card that fits perfectly in the Origenae M10 case as it's delivered with both short and long PCI trim plates. The design of the SOtM tX-USB is an all-out-assault on PCI to USB cards. The tX-USB has its own power line noise filter, individual ultra low noise regulators to power up to two attached USB devices, onboard ultra low jitter clock, onboard PCI host controller, and separate power connector. This enables the card to be powered by an external linear or battery PSU. Many computer audiophiles like to experiment with cutting the power leg from USB cables or special ordering cables without the power leg. The tX-USB has an easily accessed manual switch, next to the USB ports on the card, that enables/disables sending power over the USB cable. Users will have to check their DACs to determine if USB power is required. Some USB DACs require USB power even if the DAC itself is powered by a separate supply. The tX-USB is 100% compliant with USB 2.0 Hi-Speed and all prior USB specifications and speeds.
     


    Low quantity high quality components are never inexpensive. The SOtM components are no exception. The inline SATA noise filter retails for $65 and the tX-USB PCI card rings up at $339. Powering the tX-USB with the Jetway motherboard requires a SATA to LP4 Molex adapter (Photo 1) (Photo 2) as the motherboard ships with two SATA only power connectors. The $6 Nippon Labs SATA 15 Pin Male to Molex 4 pin female adapter should work great with C.A.P.S. v2.0 and the tX-USB. During the build process I was itching to get the server running so I created my own cable using spare parts from my music server graveyard. I recommend simply ordering the inexpensive adapter. Much easier and better looking. As a side note, Linux users will be happy to learn the tX-USB PCI card supports Hi-Speed USB 2.0 devices when used with the correct kernel.

    The most likely question CA readers are asking themselves as they read this article is, "How does it sound?" I unequivocally state the SOtM products improved the sound quality of my system when placed into the C.A.P.S. v2.0 server. In fact I was so interested to hear if these products made a difference I placed the tX-USB in the server then connected a Wavelength Audiolink WaveLink converter to a main motherboard USB port instead of the tX-USB. Old habits are hard to break. I was sorely disappointed as I heard absolutely no change with only the tX-USB installed and my USB converter to the main board. After a couple tracks I mentally retraced my steps and realized my error. Like any wise Golfer I gave myself a mulligan. With the WaveLink connected to the tX-USB (power enabled as required by WaveLink) I listened to the same tracks that I had played using the previous misconfiguration. I was pleasantly surprised to hear such a nice difference. I understand what has gone into engineering the SOtM components but I also understand far better how computers operate. How can there be a sonic difference? USB is USB isn't it? Bit transparent is bit transparent isn't it? Unfortunately there's much more to computer audio than meets the eye or the ear. While working on C.A.P.S. v2.0 a CA reader posted the following link to a discussion on Audio Asylumlink. The discussion details some of the problems associated with USB audio and the difficulties in addressing the issues. A phrase that comes to mind after reading such informative discussions is, "The more you know, the more you know you don't know."
           

           


     

    Optional Add-ins
    FireWire DAC users are also in luck with C.A.P.S. v2.0. The PCI USB card can be excluded from the design by substituting an $8 SYBA SD-VIA-FW1E1H PCI FireWire card. This card works perfect with the Weiss Engineering DAC202. The total savings is $331.
    Manufacturer Linklink | Newegg Product Pagelink

    I did not include an internal ROM drive in Pocket Server version 2.0. If needed one can use an external drive or a $90 Panasonic SATA Slim drive or a $169 Sony Optiarc Blu-ray drive. Many slot loading drives feature drive eject buttons that are not compatible with the Origenae case. Please look closely before purchasing another drive. A $5 mini SATA cable is likely required for the slot loading optical drives.
    Panasonic SATA Slim drivelink | Sony Optiarc Blu-ray drivelink | Mini SATA Cablelink

     

    Software

    Operating System
    During the design of the original Pocket Server I researched and tested a few different operating systems including Windows 7 and Voyage Linux. I've closely followed Voyage's development since that time and noted the rise of other Linux based servers aimed at audiophiles. Given the C.A.P.S. v2.0 requirements and the fact that companies such as Simple Designlink can design and build a better Linux system than I ever could I elected to bypass Linux for the Pocket Server design once more time. Linux is great but like everything in life it has an appropriate time and place. Linux is not the right fit for the C.A.P.S. v2.0 design.

    I selected Windows 7 Ultimate SP1 64-bit as the version 2.0 operating system. Most of the same reasons used for the v1.0 design hold true for v2.0. Windows 7 meets all the software based requirements for a Pocket Server. Quoting the C.A.P.S. v1.0 article, Windows 7, "[I]s capable of great sound, [is] a current OS, easy to operate and install, works with more hardware than any other OS, and is capable of bit perfect playback at all required sample rates when configured properly." CA readers familiar with the original design will likely wonder why I selected the 64-bit version when previously I saw no benefit to a 64-bit OS. The main reason I went with the 64-bit OS is I wanted the new C.A.P.S. design to be forward "thinking" for lack of a better term. It's clear the personal computer industry is moving toward 64-bit hardware and 64-bit operating systems. In fact most hardware has supported a 64-bit architecture for years. The C.A.P.S. v2.0 hardware is no exception, it fully supports 64-bit software.

    Playback / Library Management Application
    J River Media Center 16link is by far the best choice for the playback application running on C.A.P.S. v2.0. JRMC has the best mix of file format support, good graphical user interface, database functionality, customization, and most importantly audio output modes such as WASAPI - Event Style, WASAPI, Kernel Streaming, and ASIO. In addition to a great application J River has very good support for the computer audiophile community. I recently had the opportunity to visit the guys at J River, once again, and test the new $FREE Android remote control app Gizmolink. Readers with Android devices would be remiss not to give Gizmo a shot. I really like the functionality of the app and its ease of use. Currently iPhone users can control JRMC via a plain web interface or use an app such as BitRemote ($10)link.

    After everything was installed and configured I began paring down the Windows operating system including applications and services. I uninstalled nearly all of the Windows "Features" including Games, Indexing, Search, Printing, etc. Within the Windows System Properties - Performance Options I selected "Adjust for best performance". this disables all the animations and graphically intense pieces of the operating system. I also disabled System Restore, Windows Defender, Windows Firewall, and Windows Update. Obviously there is no anti-virus software on the C.A.P.S server. I also removed everything from the startup folder and Registry startup entries via MSCONFIG. As a precautionary measure I installed the Google Chrome Internet browser for the rare times I need to find album art online. This browser appears more secure than many of the Microsoft Internet Explorer versions.

    A default Windows 7 Ultimate 64-bit installation has over 140 services some of which run in the background whether or not they are required by the user. The C.A.P.S v2.0 server is currently running 33 of 144 possible services. It's certainly possible to stop or disable more of the remaining 33 services. It has been my experience that these remaining services provide a good mix of stability and software usability. I've included a list of services, status, and startup type in the document below.

    · C.A.P.S. v2 Services PDFlink

     

    Comparison C.A.P.S. Version 1.0 and 2.0

    Comparing the original Pocket Server to version 2.0 reveals this new design as the clear winner. Not only is v2.0 less expensive it offers better performance and sound quality. The motherboard, CPU, and RAM received a needed upgrade that leaves v1.0 in the dust without requiring a massive cooling apparatus or spinning fans. The most critical improvement to v2.0 is the replacement of the Lynx AES16 with the SOtM tX-USB card. This card in combination with many of the new USB DACs should make CA readers very happy. Running a USB DAC from a C.A.P.S v1.0 built-in USB port simply doesn't measure up. C.A.P.S. v2.0 is also a great system for FireWire users who will save $339 off the USB server price.

    After publishing the original Pocket Server design a few readers asked why not simply purchase a Mac Mini for $699 and call it a day? A Mac Mini doesn't meet the stated requirements of the C.A.P.S. design. Absolute Silence, no moving parts, and the ability to use an add-in card for expansion are not possible with a Mac Mini. Plus, the C.A.P.S server has increased computer audiophiles' engagement in this wonderful hobby through many user tweaks and customizations simply unavailable under OS X and a Mac Mini. Some people like to get more involved in the server part of the system while other would rather set it and forget it by using a Mac Mini. There's no right or wrong here. Both approaches have nothing to do with one's enjoyment of music or one's credibility as a music loving audiophile. It's even more likely that many CA readers enjoy both types of systems. I currently enjoy a highly tweaked C.A.P.S. v2.0 server and at the same time a Mac server, a Linux server, and hopefully soon a Meridian-Soolooslink server. This is all about furthering one's enjoyment of great music and interest in high-end audio. Nobody should care how it's done.

     

    Wrap-Up

    CASH-ListThere you have it the Computer Audiophile Pocket Server version 2.0. I sincerely hope this server design accomplishes my goal of being a hardware and software solution everyone can and will use. I'll never make a penny from this design and I'm not looking to publish a design that competes with an existing manufacturer. This design is first and foremost for all the Computer Audiophile readers who've shown such dedication to our terrific hobby and encouraged me to release an updated C.A.P.S. server. I thought about readers' likes, dislikes, and requirements throughout the entire design process. That said I didn't compromise any part of the design by sinking to the lowest common denominator. That's simply not what Computer Audiophile is about. I'm very excited to read user comments about the design, good and bad, and to see users start building their own v2.0 servers. It really has been my pleasure to design, build, and reveal the new Computer Audiophile Pocket Server version 2.0.

     

     

     

     



    The Computer Audiophile Pocket Server v2.0 piece by piece



     

     

     
    Comments 404 Comments
    1. Audio_ELF's Avatar
      Audio_ELF -
      You could put the Xonar Essense ST card in a similar computer IF you used a different case (either allowing full height cards vertically or wider with card horizonal to side of motherboard.<br />
      <br />
      However, I would argue that if you did this then your machine would not be a CAPSv2 machine...<br />
      <br />
      CAPS v2 is a complete recipie 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!<br />
      <br />
      Eloise
    1. johniboy's Avatar
      johniboy -
      and this also means that this build is pretty much useless (or at least suboptimal) for anyone who wants to use a dac with spdif input.
    1. vortecjr's Avatar
      vortecjr -
      I understand the argument for the lower power supply, but I have a few comments and suggestions. I looked for Jetway's power specifications for the CAPS v2 motherboard in there manual and in there site and I didn't find it. Anyway, most manufacturers perform a load test with a bunch of components attached to the motherboard and all running at full load at the same time. Even at full load the maximum watts used is not that much on comparable motherboards. I suspect that the power supply Chris utilized is within the recommended wattage range. However, I would recommend that you also try the larger of the three power supplies mentioned or the 105 watt unit. My tests here have shown that larger power supplies generally improve the sound especially with USB output units. Also, the specification on the tX-USB is for a max of 2 amps at 12 volts. The tX-USB may not use the full 2 amps in a typical application, but just the same that is 24 watts and a big chunk of the power supply ratting. <br />
      <br />
      Some have asked if the power supply makes a difference. I say it does! We have done tests here and some for the better and some for the worse. We also have a unit working the audio shows and it's hooked up to some very very expensive gear. I asked all kinds of questions during the build and was assured that no way the computer power altered the sound of the USB DAC. This may be true, but one thing is that the power of the computer alters the the sound of the DAC and another thing is that the power of the computer affects the quality of the signal in the first place. The manufacturers representative decided to run the server on a battery and sound improved. You could run the CAPS v2 and v1 on a 12V battery and try the on-board usb output to conduct your own tests. The issue is that a battery running the computer is not practical. The tX-USB alleviates most of the pain by cleaning the power it uses, but it can also be run on a small battery for further improvements. A smaller manageable battery is practical. Here are the parts needed to convert the tX-USB to run on an external linear power supply or a battery.<br />
      <br />
      Cables<br />
      http://www.mini-box.com/4-Pin-P4-Power-Cable_2<br />
      http://www.logicsupply.com/products/cbl_pwrpd73<br />
      <br />
      Battery<br />
      http://cgi.ebay.com/DC-12V-6800mAh-Super-Rechargeable-Lithium-ion-Battery-/220712847351?_trksid=p5197.m7&_trkparms=algo%3DLVI %26itu%3DUCI%26otn%3D3%26po%3DLVI%26ps%3D63%26clki d%3D674671822858939609<br />
      or search for 12V DC 6800mAh Lithium-ion battery if the link is broken<br />
      <br />
      Adapter<br />
      http://www.mpja.com/prodinfo.asp?number=17573+PL <br />
      <br />
      Linear power supplies for the computer I have to agree with Chris....<br />
      <br />
      Jesus R<br />
      www.sonore.us
    1. Quest's Avatar
      Quest -
      Hi Demian,<br />
      <br />
      Looks very promising and I might start with the SATA filters instead.<br />
      <br />
      I just realised the SoTM tx-USB is PCI only, and this should be a real disclaimer as some motherboards (like mine) only have PCIe. Guess I'll have to wait for a PCIe version!<br />
      <br />
      Just thinking out loud here then - is getting a PCIe usb card (non-audiophile type) still beneficial then - esp with an async dac? Since it also directly interfaces with the PCIe bus. Such usb cards also allow usage of external power supplies so that resolves the other half of the issue.
    1. 1audio's Avatar
      1audio -
      There are a number of cards available that go from PCIe to USB3(+2+1). None are "audiophile" grade, certainly not yet, but they are simple and cheap. You would probably still get some benefit from the added USB interface. If you were handy they could be modified with improved caps, power etc. but its not simple. I will make sure we note the PCI/PCIexpress issue since its has large potential confusion built in (there is also a PCIx bus, a 64 bit PCI bus). The PCI bus is considered to be obsolete but still is very useful.<br />
      <br />
    1. TimDH's Avatar
      TimDH -
      Hi Demian,<br />
      <br />
      I appreciate your no-nonsense postings in this forum. I have to say that the digital world is surprisingly hard to figure out for a rationalist like me who would like to think that digital is digital, but respects people who measure and find that it's not so simple. My question, which may be hard for you to answer: do the issues solved by filtering the hard drives and fans apply to all digital interfaces, more or less? I'm contemplating going to Peter St's DAC, after building my own PC, that uses the Juli@ PCI interface. I'm happy to put filtering in line before the sound goes out, but it'd be good to know whether the noise reduction you show in your web pages would apply to the Juli@ interface too? Thanks a lot in advance...<br />
      <br />
      Tim
    1. Quest's Avatar
      Quest -
      Well, the very last option is to use a PCI to PCIe adapter if it is really that ideal..
    1. vortecjr's Avatar
      vortecjr -
      What USB device are you planning on using?<br />
      <br />
      Jesus R<br />
      www.sonore.us
    1. 1audio's Avatar
      1audio -
      Tim:<br />
      PeterST's DAC project is really ambitious and he has put a lot of thought into solving many problems. I don't think there is anyplace on his external module that would even accept a packaged filter like the the SoTM filters. I believe he has pretty extensive power management and regulation in the DAC module. <br />
      <br />
      However the host computer would benefit from the filtering on SATA and Fan connections (if you need a fan). At a higher level you want to reduce noise at its source. Shielding noise sensitive stuff is important and necessary but the radiating noise source causes more problems and degradation and is best dealt with at the source. Its also better to design/plan for low noise that to try to reduce it later. That suggests using lower power components, with just enough power to do what you need done, since lower power means less noise.<br />
      <br />
    1. lasker98's Avatar
      lasker98 -
      Hi all,<br />
      I've been trying to read up as much as I can on this site with the goal of building my own CAPS type server. It's a fantastic site with an incredible amount of information to absorb. I had been waiting until the new CAP 2 was published before starting my build.<br />
      I have to say it's thrown me for a bit of a loop since I had been assuming I would be running S/PDIF digital RCA out from the server into my Bryston BP25DA (preamp with built in dac which has only RCA digital inputs).<br />
      This new CAPS 2 server is based on no sound card and USB outut to dac which leads to many questions for me. <br />
      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? <br />
      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?<br />
      If USB is not "better" then the digital out via sound card option, then would I be able to add a PCI sound card to the CAPS 2 and get my digital sound outout to my dac this way? Would the spec'd 60 W power supply run the additional sound card or would something else be needed?<br />
      There's also quite a cost difference in using USB out as spec'd which would require the $339 PCI to USB card plus the Halide bridge for $450, compared to using a sound card, where even using a Lynx card would still come in cheaper.<br />
      I'm sure there's many things I'm not taking into account yet but I would very much appreciate any suggestions or feedback.<br />
      I'm sure there are many others in a similar situation with a dac with no USB input. Hopefully answers to my post will be helpful for them as well.<br />
      Thanks in advance for your help and thanks as well for a great site and place to be able to learn about this topic.<br />
      <br />
      Bill
    1. Quest's Avatar
      Quest -
      Plan to use this with the Chord QBD 76 HD DAC which has async usb input.<br />
      <br />
      I already have a fanless hfx classic PC based on a i5.. just looking to maximise the performance. I think I can use a PCI to PCIe adapter to use the SOTM tx-USB but as with all adapters, will have to accept a slight drop in performance probably.
    1. Quest's Avatar
      Quest -
      Breaking this up into a few answers for you:<br />
      <br />
      1. USB sound out in CAPS2 should theoretically sound better than a generic soundcard (not the really expensive ones) just because of further isolation. My own experience is that Lynx sounds better than first gen usb/spdif converters but not second gen like the Wavelink. Furthermore, it is difficult to get the right cabling done up (or AB comparison) for Lynx due to the connectors.<br />
      <br />
      2. Regardless whether you go Lynx OR usb/spdif converter, the CAPS2 should make an improvement. Moving to fanless PC for me already gave quite abit better sound even though I was using a async usb dac.<br />
      <br />
      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.<br />
      <br />
      IMO the most critical things to get right in the PC:<br />
      - Power supply, power cord, power distributor<br />
      - Going fanless, SSD. Using the right usb slot if using motherboard.<br />
      - Software
    1. vortecjr's Avatar
      vortecjr -
      I was going to send you something left over from an R&D project to try out, but it will not work with that DAC. I might have something else, but I need to look into it. I'll let you know if I find it.<br />
      <br />
      Jesus R<br />
      www.sonore.us
    1. JR_Audio's Avatar
      JR_Audio -
      Hi Chris<br />
      <br />
      Thank you for the C.A.P.S. 2 article. Nice one, with some audiophile tweeks. Also for mentioning BitRemote as an alternative to RiverMote.<br />
      <br />
      Juergen
    1. Audio_ELF's Avatar
      Audio_ELF -
      Hey folks.. While it's great to discuss alternative recipes for servers; remember anything outside of Chris's suggested items is no longer a CAPSv2 server so (IMHO) some of this discussion would be best taken into new threads - especially any discussion off topic from commercial entities. I'm not sure anyone has broken the rules (in spirit or technicality) but some posts (IMO) have headed that way. <br />
      <br />
      Eloise
    1. Bob D's Avatar
      Bob D -
      Chris,<br />
      <br />
      Thanks for your creativity in advancing high performance and affordable music servers. <br />
      <br />
      I have a few comments and questions...<br />
      <br />
      In addition to your design requirements, I have need for HDMI and firewire for use with my Weiss DAC202. I'm considering the ASUS http://usa.asus.com/Motherboards/Intel_CPU_on_Board/AT5IONTI/ motherboard given it has HDMI. In addition, it does support USB 3.0 which may offer a very fast means to deliver music data files to the server via USB 3.0 external drive(s). <br />
      <br />
      Here are my questions:<br />
      1) Would using the motherboard USB ports attached to external USB disk storage compromise the spirit of your overall design basis? If so, how?<br />
      2) Would you suggest using perhaps a second SOtM power filter and external power supply on the external USB drives assuming the voltage rails are within operating tolerances of the drives? Currently I do have the AC-side of my USB external drive power supply plugged into my PS audio Power Plant. I'm not certain if the power supply noise is introduced during the AC rectification process or is simply noise from the originating AC. I don't know if the the idea of filtering the Power on the USB drives is necessary. Your thoughts?<br />
      3) Where in the M10 case did you mount the SOtM?<br />
      4) What brand and model of a Firewire card would you suggest for the ASUS PCIe slot?<br />
      5) What didn't I ask that I should have?<br />
      <br />
      Thanks Chris.<br />
      <br />
      <br />
    1. Valvefan's Avatar
      Valvefan -
      Hi Qwest,<br />
      <br />
      Who makes a PCI to PCIe adaptor? My MB has only a PCIe slot. Can I use the SoTM USB card?<br />
      <br />
      Valvefan
    1. vortecjr's Avatar
      vortecjr -
      FYI: SOtM advised me today that not all PCI to PCIe adaptors are compatible. I looked just for kicks today and didn't find any, but it was just a quick search. Either way SOtM is looking into making a PCIe version as well....<br />
      <br />
      Jesus R<br />
      www.sonore.us
    1. freddie40's Avatar
      freddie40 -
      1) They wanted it to be absolutely silent: I consider the Mac Mini to be that if you have a SSD.<br />
      <br />
      2) Capable of Great sound: I consider the Mac Mini to be that.<br />
      <br />
      3) Great looking: I consider the Mac Mini to be that.<br />
      <br />
      4) No moving parts. If you replace the hard drive with a SSD then it doesn't. Their machine does not have a DVD so the Mac Mini wins.<br />
      <br />
      5) Fairly inexpensive. The C. A. P. S. v2.0 is more than $1400 and only has 4GB of RAM. The MAC mini wins on this.<br />
      <br />
      All of the rest are the same.<br />
      <br />
      Except for the USB interface and the Power Supply the C. A. P. S. v2.0 is nothing real special. The processor is slower (1.8 GHZ), less RAM (4GB Maxed out).<br />
      <br />
      So, a stock Mac Mini with a SSD drive and 8GB of RAM is about $900.<br />
      <br />
      The C. A. P. S. v2.0 with a slower processor, 4GB of RAM and runs Windows is more than $1400.<br />
      <br />
      Does the USB and Power supply make up for the slower processor and less RAM? I guess I would call it a draw.<br />
      <br />
      Therefore you would go by price, the Mac Wins <br />
      <br />
      Dave (A Happy Mac Mini User)
    1. Quest's Avatar
      Quest -
      PCI to PCIe adapters are indeed available. Since I am in Asia I wrote to SOTM about it before and they recommended me this:<br />
      http://www.carpckorea.com/front/php/product.php?product%20no=4881&main%20cate%20no=141 &display%20group=1<br />
      <br />
      Can't tell which card has better build quality though.<br />
      <br />
      Jesus, wow, any idea when their PCIe version will be out? That'd be much better of course.<br />
      <br />
      Also, thanks for the thought on your 'R&D leftovers'. Always open to experiment.
  •