• Music Server Enhancement Ideas

    I continually research methods and products to improve sound quality, music server performance, and convenience all with audiophiles in mind. This research includes, among other things, talking to many manufacturers, engineers, dealers, and CA readers from around the globe. It's always nice to hear what other people are doing to improve their music listing experience. As some readers know I've been researching isolation devices to isolate the computer from audio components, shared power sources, and noisy switching power supplies. Like everything else in life I found there is more than one way to get the isolation job done. My conversations with engineers have ranged from those who recommend as much isolation as possible to those who recommend virtually no isolation other than what's built into the components. Using these conversations and my own searches I've put together a handful of products Computer Audiophile readers may want to investigate. As always, don't take any one person's word about the effectiveness or ineffectiveness of these products. Read information from as many sources as possible and try out the products for yourself if feasible.


     

    HyperMac External Battery $200-500

    This external battery connects to a MacBook / Pro via the laptop's standard power port. Using a HyperMac external battery enables the MacBook to remain disconnected from a wired power source for 30+ hours. There's nothing better at isolation than completely disconnecting from the wall outlet. This alleviates all possibilities of ground loops and power related computer noise getting into the audio system. I've done several listening tests and believe in my system running on battery power results in improved sound quality. I hear the improvement even though I have a dedicated power sub-panel and circuits for my listening room and a copper ground rod going directly into the earth from my sub-panel. The HyperMac batteries come in four sizes with varying watt-hour capacity.

     

    Oyen Digital MiniPro Portable Hard Drives $100-245

    I've been using an Oyen Digital MiniPro 750GB hard drive connected to my MacBook Pro for a few weeks. I have nothing but great things to say about this portable drive. I'm using a FireWire 800/400, USB model that receives power from a FireWire or USB port, or an external power supply. I power the drive via FireWire or USB (single USB port) without any issues. One great thing about this is it removes a noisy switching wall wart power supply from the system and keeps my music server completely isolated from the power source used by my audio system. Again, complete disconnection is the best isolation available. The Oyen Digital MiniPro portable series drives use all 2.5" (laptop) disks and range in size from 160GB to 1TB with speeds of 5200, 5400, and 7200 RPM. The smaller 2.5" disks use less power and produce less noise than standard 3.5" (desktop) disks. The solid aluminum enclosure is well built, looks nice, and dissipates heat first and foremost. The drive enclosure does heat up during periods of heavy use, but hopefully this means the enclosure is dissipating the heat well. The MiniPro series does not require a fan to stay within the specified operating temperature range. In addition to these nice features the MiniPro uses the Oxford 934 chipset (OXUF934SSA). More geeky audiophiles will realize the significance of this chipset. The 934 chipset is featured in many external drives used by engineers with applications like ProTools and Avid that have very exacting external drive performance requirements. The MiniPro series drives also spin up/down depending on the computer's status (awake or in sleep mode).

    The drive works equally well on Windows and Mac platforms. I currently have music storage for a J River Media Center library and an iTunes library on the 750GB version. My complete library doesn't fit on this drive but a large number of my "most listened to" albums do fit on the drive. Maybe I need the 1TB version. I could also purchase a couple of these drives and daisy chain them together using this built-in capability of FireWire interfaces. During my review of the Weiss DAC202 I connected this drive to my MacBook Pro's FireWire 800 port and the DAC202 to this drive's other FireWire 800 port with a FW800/400 cable. I didn't experience any show stopping performance issues. I also brought this drive with me to local coffee shops and connected it to my MacBook Pro via FireWire while my Wavelength Proton was connected via USB. This is a great combination for the audiophile on the go.
    NOTE: Oyen will release a USB 3.0 version of the MiniPro drives very soon.

     

    Opticis Optical USB Extender M2-100-XX $189-345
    Opticis FireWire Repeater M4-200 $795 & Fiber Cable $35+

    The next two products not only provide an additional layer of isolation they also enable USB and FireWire devices to be placed far beyond the limits of standard USB and FireWire cables. A few high end manufacturers have used the optical USB extender at audio shows with very good results. Using the USB extender with an asynchronous device is ideal because the clock is located after the signal has traversed the optical link, thus does not increase the jitter. The USB extender consists of four internal glass fiber cables with a single USB port on each end. The computer is totally isolated from the DAC and offers mmunity from EMI and RF signals, but there is no free lunch. The extender does require a small power supply on the DAC end of the cable. I talked to a couple well respected audio engineers who have used this device. One simply built a linear power supply to replace the stock switching supply. The other said the switching power supply was better than the power derived from the computer's USB port and was not a show-stopper. Opticis does offer a USB extender (M2-200-XX) with USB power eliminating the need for the external power supply but as I said there is no free lunch. This device removes the galvanic isolation between the computer and the DAC. Thus, it's only an extension not an isolation device. NOTE: These USB extenders are USB 1.1 compliant and will not work correctly with USB 2.0 devices.

    The Opticis FireWire Repeater is somewhat simulate to the USB repeater but the cost is several hundred dollars more than the USB device. This repeater is RF and EMI resistant as it uses industry standard fiber optic cables with LC terminations. The FireWire repeater can be daisy chained in a number of configurations with optical cables up to 500 meters each. The FireWire repeater may require the included external power supply if the FireWire device opposite the computer requires bus power from the FireWire port and the built-in power indicator is not illuminated. The FireWire repeater is completely compatible with FireWire 400 and 800 chipsets. I haven't' used this device yet so I can't comment on any performance benefits or issues. This is simply an FYI to readers looking to try some possible system enhancements using solid engineering principles.

    Both devices work with Most versions of Windows, Apple OS X, and Linux.

    USB Optical Extender Product Page Link | USB Data Sheet PDF | USB Applications PDF

    FireWire Repeater Product Page Link

     

    Baaske Network Medical Isolator 5kV MI 1005 $190

    This last product definitely uses the belt and suspenders approach. It's built for the medical industry to filter out "leakage currents and voltages" over a standard copper based network. This network isolator is the only one I could find that is fully 10/100/1000 Gigabit Ethernet certified without cable length limitations. Even though twisted pair Ethernet cables have built-in galvanic isolation (belt) one never knows when they'll need up to 5000 volts of AC isolation (suspenders) . I believe the device is more beneficial for use with shielded Ethernet cables as the shield itself is not galvanically isolated. Use of shield cables is a rare occurrence in a home network.

    Product Page Link | Additional Product Page Link

    General Information PDF | Technical Information PDF

     


    There you have it, a few products that have at least peaked my interest when it comes to isolating my audio components from my music servers. Fortunately most of these products are less expensive than the sales tax on many audiophile cables :~)


     


     


     
    Comments 38 Comments
    1. Tipper's Avatar
      Tipper -
      Good job Chris.<br />
      Just seeing if it's cost effective to have one sent to England after postage and Tax.<br />
      Would you be happy to use this as your main storage given your experience of it so far?<br />
      Just love the Ethernet Isolator. Talk about bullit proof.
    1. MR's Avatar
      MR -
      Following a hint from Chris, I tried this out with some mixed results. I used both the standard supply and a 5V li-ion battery. For USB devices that are having problems with grounds, power, or RFI, the Opticis improved the sound -- a lot.<br />
      <br />
      For a USB interface device (ART Legato) that already achieves galvanic isolation and has its own internal power, I got some improvement until the manufacturer supplied a USB cable with no internal power wires -- this sounded better than the Opticis.<br />
      <br />
      Where I was hoping to hit a home run was with the HiFace USB->S/PDIF interface which uses USB power. The Opticis cable and the battery seemed like the perfect combination since the HiFace would have complete galvanic isolation as well as a solid DC source. Unfortunately, the Opticis cable appears to the system as a USB hub and the HiFace drivers could not find the HiFace; the device could not be selected for playback even though it was known to Windows.<br />
      <br />
      It was, however, a nice theory.<br />
    1. proth's Avatar
      proth -
      Furman Sound makes a Reference line of home theatre products that feature symetrical balanced power. In addition, the large transformer that creates the balanced power (via a precision center tap), has separate windings for each duplex outlet on the unit, and additionally floats the ground. I've spoken at length with the designer, Garth Powell, and he certainly knows a lot about power, electrical engineering, music, relevant compromises, and the fact that in audio "everything matters." Furman claims that due to their approach, each duplex has isolation at least as good as running a dedicated circuit from the breaker box to each outlet. In my experimentation, this has been true. With a plasma hooked up to one duplex, and my MacBook / external hard drive plugged into another, there is no discernable effect on the rest of my system (i.e., the same results as when the plasma is unplugged and I'm running the MacBook from battery power with files on its internal hard drive).<br />
      <br />
      The 4-outlet (2-duplex) unit (IT-Reference 7i) is great for creating a Chinese Wall of power to separate switching power supplies and the nasties they generate from you audio system. Something to consider.
    1. sheppard's Avatar
      sheppard -
      I've only been using this hard drive from OCW the past few weeks and haven't had any issues with it. <br />
      http://eshop.macsales.com/shop/firewire/EliteALmini/eSATA_FW800_FW400_USB<br />
      <br />
      It appears to be quite similar to the Oyen Digital MiniPro (chipset, cost, size)
    1. wgscott's Avatar
      wgscott -
      The external drives look great. I am now glad I have procrastinated.<br />
      <br />
      A couple of basic questions:<br />
      <br />
      1. Bigger ones seem to rotate slower. Is this ever an issue with music? I want to get the 1 TB firewire 800.<br />
      <br />
      2. Is there any disadvantage to powering it via firewire vs. the DC power supply?
    1. JR_Audio's Avatar
      JR_Audio -
      Chris, nicely written, about some toys for us audiophile geeks.<br />
      <br />
      Juergen<br />
      <br />
      PS: @MR: The HiFace won’t go with the Opticis, not because of the introduced hub, but because of the needed USB 2 interface for the HiFace, instead of the USB 1.1 of the Opticis.
    1. breadvan's Avatar
      breadvan -
      I have also taken the advice of other users on the forum and gotten an Oyen Digital MiniPro FW800 external drive, the drive works as advertised, however, there are issues that notebook and Windows 7 users might want to be aware of. I use a HP Elitebook 2530 NB.<br />
      <br />
      1. If you have an onboard FW400 port it might not provide enough juice to run your portable drive, in my case I used the Oyen supplied DC to USB cable, problem solved but one more cable running around;<br />
      <br />
      2. There is known issues regarding the default Windows 7 FW driver, in my case, even switching to the suggested 'legacy' FW driver my Oyen still would not work. After getting an FW400 ExpressCard with TI chipsets solved my problem, a bit more to haul around, nothing big deal, but not from a simplicity angle.<br />
      <br />
      The Oyen runs hot, but I guess like what Chris says it is doing its job but I would say proper ventilation is a must, unless you don't worry about hard drive failure.<br />
      <br />
      All in all, a much better solution for me than streaming music from my NAS, one less thing to worry about.
    1. The Computer Audiophile's Avatar
      The Computer Audiophile -
      Hi breadvan - Thanks for the information. I'm a little surprised you needed the FW400 TI ExpressCard. The Oxford chipset on the Oyen drives should be no problem for Windows. I guess the key word is <u>should</u>. Did you talk to anyone at Oyen about the issue? They have been very helpful to many other readers. <br />
      <br />
      Anyway, thanks again for the info.
    1. breadvan's Avatar
      breadvan -
      Hi Chris, there is nothing wrong with the Oyen drive, as I said, they work as advertised and like you said their tech support is first rated. <br />
      <br />
      The issue is with the default Windows 7 FW drivers not working with every FW devices out there, the issue has been noted and discussed online since Windows 7 RC version.<br />
      <br />
      Hopefully other users will not be disheartened if they ran into the same situation, and know there is a workaround. Now my Oyen drive works flawlessly after using the 'Legacy' driver and the transfer speed is MUCH faster than USB2.0 on my NB.
    1. rayhil's Avatar
      rayhil -
      These bus powered drives look very nice; particularly with the advantage of avoiding another power supply and cable. A few questions:<br />
      Has anyone compared the two drives?<br />
      Any advantage to the 5400 vs 7200 versions in terms of drive noise?<br />
      Finally, on the Oyen site, they push Shadow 4 as a backup solution with the drives; any experience or advice on this versus another backup program?<br />
      <br />
      Great job Chris.
    1. ericuco's Avatar
      ericuco -
      This might be a silly suggestion but could you use a simple timer box (outlet) in conjunction with HyperMac battery so that you can keep it charged at all times. Set the timer to come "on" say late at night and then turn "off" during the day when you might want to listen to music. My problem with something like this is remembering to plug it into the wall. This way could always have the battery plugged in but it would only be connected to the power grid when you would not be listening to music.<br />
      <br />
      Just a thought.
    1. The Computer Audiophile's Avatar
      The Computer Audiophile -
      Hi Eric - That appears to be a decent idea but I don't know enough about how the timers operate to know if they would defeat the purpose of total isolation. Hopefully someone can chime in here with more info.
    1. tarquineous's Avatar
      tarquineous -
      I think the timer is a great Idea. I have an older Panasonic and a Sansui that I picked up at a garage sale. Both work fine, with the Sansui being the nicer made unit. It's good enough to place in a high end rack.<br />
      <br />
      I've looked inside, and basically the switch disconnects the ungrounded conductor(Hot), assuming its plugged in correctly. But in any case there would be no incomming noise or current from the house circuit. <br />
      <br />
      There can however be RF existing like any other wire. Whether it can get in through the battery circuit is another question. Probably not, but what you can do is put a large ferrite on the cord where it enters the battery pack. There may be one in the charger if it was designed that way, but most likely not. <br />
      <br />
      If you have one of those Furmann units, or equivalent, plug the timer into it.
    1. woodcans's Avatar
      woodcans -
      I have had the OWC 1TB drive for several months. It's a great drive, quiet and has performed flawlessly for me. It's my main source now and I can keep my entire music collection in lossless format, with the exception of my hi-res stuff that has enormous file sizes. I ordered the Oyen this week from the Amazon deal. <a href="http://gallery.me.com/jjudger#100102">Here are some comparison pics.</a> <br />
      <br />
      I have only had it for a couple of days, but so far I like the Oyen form factor much better and its LED is much less intrusive. Both run hot and after copying my 500+GB music collection over they both were of similar temp at the heatsinks. The oyen also has an additional fw400 port which is handy for firewire dacs, thereby leaving an open fw800 port. I do like the rounded edges of the OWC, makes it easy to slide into a pouch in my messenger bag. And the drive in the OWC is cushioned by rubber bumpers for a little added shock protection. <br />
      <br />
    1. rayhil's Avatar
      rayhil -
      Thanks for this valuable feedback. <br />
      Is there much size difference between the two drives or much noise difference - as I'd like to use one as my primary storage (no power cable) and retire my 3.5 OWC drive to backup use.
    1. ggking7's Avatar
      ggking7 -
      Has anyone considered the Ultravox+battery combo? It's perfect USB isolation.<br />
      <br />
      http://www.computeraudiophile.com/content/USB-isolation-experiment-great-success
    1. wgscott's Avatar
      wgscott -
      Amazon appears to have a <a href="http://www.amazon.com/MiniPro-External-FireWire-Portable-Drive/dp/B003AXYA28/ref=sr_1_15?ie=UTF8&s=electronics&qid=1278639689&s r=1-15">a real good deal</a> on one of these firewire drives.<br />
      <br />
      Bummer. They fixed the decimal problem. I guess someone decided $18K was too much to pay.
    1. woodcans's Avatar
      woodcans -
      I do not detect any difference in noise, both are very quiet, but can be heard if close to your ears.<br />
      <br />
      As for size, the OWC is slightly bulkier in all three dimensions. <br />
      <br />
      Of note, when I have both drives running, there is more vibration (as detected by putting my hand on the drives) coming from the Oyen unit.
    1. realmassy's Avatar
      realmassy -
      What's the actual difference between 5400 and a 7200 drive, when used as simple music storage, via firewire? I understand the 7200 rpm drive is faster, but what about noise and heat?<br />
      Thanks
    1. wgscott's Avatar
      wgscott -
      I'm trying to decide whether to get a mini drive and power it via firewire 800 from my mac mini, or to get an ordinary drive with an external power supply.<br />
      <br />
      The thing that concerns me is that if the external drive draws power from the mini, which now has a built-in power supply, it might cause the mini to heat up more, which might be more harmful than whatever noise might be generated by an external power supply.