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    The Computer Audiophile

    Weiss Engineering DAC202 Review

    DAC202-front-thumb.jpgOver the last couple years I’ve listened to people utter the phrase, “I’m waiting to see how it all shakes out." Without context it’s entirely appropriate to assume we were discussing the global economic meltdown. However these conversations revolved around music servers, interfaces, and differing computer audio technologies. People were frequently delaying the purchase of a new DAC because of their uncertainty about the future of the marketplace. Specifically uncertainty about interfaces such as USB, FireWire, Ethernet, AES/EBU, and S/PDIF. These interface options have caused serious hesitation from the same people who eagerly accepted Compact Disc technology as if it offered perfect sound forever. Equally hesitant are audiophiles feeling a bit burned by SACD and DVD-Audio. Audiophiles shouldn’t let the past halt their potential heightened enjoyment of this wonderful hobby. There’s no format war going on. Many different interfaces and technologies will flourish in the years to come. Falling victim to <a href="http://en.wikipedia.org/wiki/Analysis_paralysis">analysis paralysis</a> or suffering from <a href="http://www.urbandictionary.com/define.php?term=Alligator%20arms">alligator arms</a> are two easily curable conditions. Ambivalent audiophiles, It’s time to <a href="http://en.wikipedia.org/w/index.php?title=Fish_or_cut_bait&redirect=no">fish or cut bait</a>.

    [PRBREAK][/PRBREAK]

     

     

     

    <b>What’s The Hold Up?</b>

     

    There’s little doubt that computer based audio is the future of high end playback. In a nod to <a href="http://www.youtube.com/watch?v=Kn6uqwSjDjY">Rusty and Audrey Griswold</a>, the only remaining question is “Are we there yet?" The answer to that question is yes, as long as the right combination of software and hardware are selected. The perpetual naysayers who won’t be satisfied until a music server is easier to operate than a toaster should also look at a traditional dCS system with three or four separate boxes and say the spinning disk isn’t there yet because they can’t operate the dCS system with these ease of a cassette player. I’ve never heard anyone suggest the latter and I don’t see why the argument should hold true when it comes to music servers. Music servers, like most technology, can be placed on a continuum from simple to complex. Logical factors in the “Are we there yet" analysis should be related to sound quality, sample rate support, feature sets, interface design, and bit transparency.

     

    What does all this have to do with the Weiss Engineering DAC202? The DAC202 could easily be the component to knock audiophiles off the fence and on to the next phase of high end audio. The DAC202 may be the best antidote for the aforementioned audiophiles suffering from alligator arms and analysis paralysis. The sound quality, sample rate support, feature set, interface design, and bit transparency testing built into the DAC202 should satisfy audiophiles from the most jaded old schooler to the early adopters looking to replace an existing DAC.

     

    <b>Weiss Engineering DC202 Evolution And Lineage</b>

     

    Computer audiophiles who’ve been using music servers for weeks, months, and years are likely familiar with the name Weiss Engineering and eponym Daniel Weiss. Professional engineers, even more familiar with Daniel Weiss, have used his components for decades. In fact a recent visit to Paul Stubblebine Mastering in San Francisco demonstrated Weiss Engineering’s penetration into the “audiophile" facilities where many of our favorite albums are mastered. Needless to say Daniel Weiss is one of the best engineers in the business at designing components that have made and played high quality music.

     

     

    <a href="http://images.computeraudiophile.com/graphics/2010/0617/Stubblebine/IMG_0178.JPG" class="thickbox" rel="stubblebine"><img src="http://images.computeraudiophile.com/graphics/2010/0617/Stubblebine/IMG_0178-small.jpg"></a>   <a href="http://images.computeraudiophile.com/graphics/2010/0617/Stubblebine/IMG_0179.JPG" class="thickbox" rel="stubblebine"><img src="http://images.computeraudiophile.com/graphics/2010/0617/Stubblebine/IMG_0179-small.jpg"></a>   <a href="http://images.computeraudiophile.com/graphics/2010/0617/Stubblebine/IMG_0180.JPG" class="thickbox" rel="stubblebine"><img src="http://images.computeraudiophile.com/graphics/2010/0617/Stubblebine/IMG_0180-small.jpg"></a>   <a href="http://images.computeraudiophile.com/graphics/2010/0617/Stubblebine/IMG_0181.JPG" class="thickbox" rel="stubblebine"><img src="http://images.computeraudiophile.com/graphics/2010/0617/Stubblebine/IMG_0181-small.jpg"></a>   <a href="http://images.computeraudiophile.com/graphics/2010/0617/Stubblebine/IMG_0182.JPG" class="thickbox" rel="stubblebine"><img src="http://images.computeraudiophile.com/graphics/2010/0617/Stubblebine/IMG_0182-small.jpg"></a>   <a href="http://images.computeraudiophile.com/graphics/2010/0617/Stubblebine/IMG_0183.JPG" class="thickbox" rel="stubblebine"><img src="http://images.computeraudiophile.com/graphics/2010/0617/Stubblebine/IMG_0183-small.jpg"></a>   <a href="http://images.computeraudiophile.com/graphics/2010/0617/Stubblebine/IMG_0184.JPG" class="thickbox" rel="stubblebine"><img src="http://images.computeraudiophile.com/graphics/2010/0617/Stubblebine/IMG_0184-small.jpg"></a>

     

     

     

    In June 2008 I reviewed DAC202 predecessor the <a href="http://www.computeraudiophile.com/weiss-engineering-minerva-firewire-dac-review">Minerva</a>. It was a great component but at the time options for computer audiophiles were much more limited. The Minerva was a big fish swimming in a little pond. That certainly doesn’t diminish the Minerva’s performance but it places proper perspective on my assessment. In December of the same year I reviewed the Berkeley Audio Design <a href="http://www.computeraudiophile.com/Berkeley-Audio-Design-Alpha-DAC-Review">Alpha DAC</a> and subsequently crowned it my favorite DAC. I placed the Alpha above the Minerva for a few reasons namely soundstage, volume control / preamp capability*, HDCD indicator**, and sample rate display.

     

    Nearly two years later Weiss Engineering has responded in true leapfrog fashion. The DAC202 was not built to equal the competition or as a minor tweak of the Minerva. The DAC202 was built to surpass the competition and previous Weiss DACs. After investing well over two hundred hours actively listening through the DAC202 in every sensible configuration I unequivocally state Weiss Engineering has handily surpassed the competition and all previous Weiss DACs in its class.

     

    <FONT SIZE="-2">* At the time of review the Minerva did not have volume control. Weiss Engineering did enable volume control in later releases of the Minerva, but the implementation was clearly an afterthought and awkward to use.</font>

    <FONT SIZE="-2">** The HDCD indicator on the Alpha DAC is a rudimentary indication of bit transparent audio reproduction. When playing an HDCD encoded file the indicator should illuminate. If the indicator remains dark this signifies playback is not bit transparent. However, there remains a slim chance that the indicator will illuminate without bit transparent playback. In other words, if the indicator is off and it should be on something is wrong. If the indicator is on there is a good chance playback is bit transparent, but bit transparency is not guaranteed. I have successfully played an HDCD encoded file that produced major distortion and short drop-outs yet consistently illuminated the HDCD indicator. Thus the rudimentary categorization of the HDCD indicator. </font>

     

    <b>Weiss Engineering DAC202 In Detail</b>

     

    At $6,670 USD the Weiss DAC202 has increased in price as much as performance over its predecessors. I’ll leave judgements of value up to individual readers as each of our monetary decisions involve vastly different variables. I will say a significant percentage of audiophiles have spent many times the amount of the DAC202 price premium on “upgrades" with far less overall impact.

     

    <img src="http://images.computeraudiophile.com/graphics/2010/0617/index-66.jpg" style="padding: 5pt 10pt 5pt 5pt;" align="left">The <b>fit and finish</b> of the DAC202 has been improved nicely over previous Weiss DACs. The new headphone socket, volume control, and LCD display elevate the look of this unit to the audiophile standard. The Minerva and to a much greater extent the DAC2 look very utilitarian even though their lackluster form doesn't enable enhanced function. The rear of the DAC202, although very compact, is laid out ergonomically. I had no problems during the review period inserting and removing all types of cables. The addition of a gold headphone socket to the DAC202 raises the versatility of the unit to another level. Most manufacturers don’t offer a headphone output on products at this price point. Weiss Engineering has wisely considered the continually growing high quality headphone market with the inclusion of a standard quarter-inch (<b>T</b>ip, <b>R</b>ing, and <b>S</b>leeve connector) headphone output. The addition of a rotary encoder knob, referred to here as a volume control, was a must not only to improve upon previous designs but to enable menu navigation with ease. The knob itself is of high quality and spins in the overly obvious clockwise and counter-clockwise directions using detents for every half or full db adjustment. These detents, unlike the new Antelope Zodiac DAC controls, enable the listener to recall an exact volume level when desired. In addition the volume control is used to select menu items by pushing the knob inward. The DAC202’s three inch LCD display (measured diagonally) is somewhat easy to see from a nine to twelve foot listening position and a appropriately understated when when automatically dimmed. Significant information such as volume level, phase, and filter are easily visible while the active interface and sample rate may be more difficult for some listeners to read at a distance. The display is nicely recessed into the solid aluminium faceplate. This faceplate that will also be available in black once the second production run is underway. The DAC202 ships with a nicely built substantial but not over engineered remote control. After a few hours of use the important buttons such as volume and power can be memorized as they are not lost in a sea of useless buttons. The DAC202 remote offer ten buttons, all of them either discreet or toggle selectors with the exception of volume up and down. It’s very nice to select a specific interface instead of scrolling through the list of available interfaces.

     

     

    <center><a href="http://images.computeraudiophile.com/graphics/2010/0617/DAC202-front-large.jpeg" class="thickbox" rel="dac202-hardware"><img src="http://images.computeraudiophile.com/graphics/2010/0617/DAC202-front-small.jpeg"></a>   <a href="http://images.computeraudiophile.com/graphics/2010/0617/DAC202-back-large.jpeg" class="thickbox" rel="dac202-hardware"><img src="http://images.computeraudiophile.com/graphics/2010/0617/DAC202-back-small.jpeg"></a></center>

     

     

     

    The <b>feature set and technical capabilities</b> of the Weiss DAC202 are extremely good. Directly addressing three of the four reasons I previously selected the Alpha over the Minerva are the new volume control, bit transparency check, and seemingly mundane sample rate display. In addition to these three features and capabilities the Weiss DAC202 offers a critically and consumer acclaimed asynchronous FireWire interface. The DAC is also capable of sending word clock out to an audio card in an asynchronous-like fashion. Either way the Weiss DAC202 retains the critical role of master clock.

     

    <a href="http://images.computeraudiophile.com/graphics/2010/0617/dac202-remote-large.jpeg" class="thickbox" rel="dac202-hardware"><img src="http://images.computeraudiophile.com/graphics/2010/0617/dac202-remote-small.jpeg"style="padding: 5pt 10pt 5pt 5pt;" align="left"></a>More and more audio systems consist of digital only sources and are less dependant on a traditional preamplifier. Digital to Analog converters with <b>volume control</b> have thus become increasingly popular. In 90% of audio systems this popularity (bypassing an analog preamp) serves the system well. It’s a rare occasion when inserting a preamp improves sound quality but it does happen. The volume control implemented in the Weiss DAC202 may increase that percentage to 99% because of its flexibility and superior design. The DAC202 features a coarse analog / fine digital volume control on both the main and headphone outputs. The DAC is capable of four selectable coarse settings via relay in the analog domain and fine level adjustments in the digital domain. Listeners who insist on using a preamp can defeat this level control on the main output only. One of the beauties of coarse analog level control is the capability to closely match the input sensitivity of an amplifier. My McIntosh MC275 has a sensitivity of 1.2 volts via unbalanced RCA inputs and 2.5 volts via balanced XLR inputs. Using the balanced XLR outputs of the DAC202 I set the coarse analog level to 2.12v With a closely matched voltage setting the digital volume attenuation does not have degrade the sound quality like it can with an unmatched pair of components. This matching allows use of the digital volume control over its entire range. The maximum bearable listening volume is reached at 0 db, not a level near -12 db of attenuation. For example a DAC with fixed output voltage of 6v feeding 2.5v MC275 power amplifiers will require either a preamp or major volume attenuation at the DAC to achieve proper listening levels. DACs with well implemented 32 bit or 24 bit digital only volume controls and proper dithering techniques can handle quite a bit of attenuation without deleterious effects to the sound quality <a href="http://files.computeraudiophile.com/2010/0617/Digital_Level_Control.pdf">[Digital Level Control PDF]</a>. However a coarse analog / fine digital volume control allows the ideal balance of analog voltage matching with limited or no digital attenuation or sonic degradation. The 7.6 db difference between 6v and 2.5v may seem minimal at first blush, but consider the difference just 1 db can make during listening evaluations. The DAC202’s four selectable coarse analog settings are 1.06, 2.12, 4.15, and 8.15v. The fine digital level adjustments are full db steps from -60 db through -20 db and half db steps for levels between - 20 db and 0 db of attenuation. The coarse analog / fine digital volume control is by far my favorite feature of the Weiss DAC202.

     

    A very popular question on the Computer Audiophile forum is, “How do I check for bit transparent output?" Until recently a true test of bit transparency required very expensive and sophisticated engineering test equipment. Now this test can be accomplished with a couple mouse clicks and absolutely no engineering knowledge. The Weiss DAC202 features a <b>built-in bit transparency check</b> that works in conjunction with Weiss Engineering supplied test WAV files. This feature is easily the most underrated and most needed feature in all of computer based high end audio. If the source signal is not perfect there’s no way to make it perfect down the line. Sound quality can only get worse when starting with a sample rate converted or reduced bit depth digital signal. Bit transparency is akin to playing lossless files. Most people easily realize the sonic consequences of ripping, storing, and playing lossy MP3 files. But, many people don’t realize when their bits are butchered because they’ve never heard their system produce bit transparent audio. Depending on the level of processing done to the digital signal by the computer operating system or playback application there may be no difference between the sound quality of a lossy MP3 and heavily processed non-transparent digital signal [bit opaque :~)] . Perhaps injured equally by the lack of bit transparency in user’s systems are the DAC manufacturers. Countless times I’ve talked to people who’ve completely written off great sounding DACs because of perceived poor sound quality. Yet these same users had no way of knowing if playback was bit transparent. Judging the quality of a component further down the chain with irreversibly broken, terribly processed music is a disservice to the listener, the manufacture, and anyone who comes in contact with the user’s opinion whether verbal or written online. The Alpha DAC has its HDCD indicator and as I’ve already mentioned it’s far from infallible. The Weiss DAC202’s built-in bit transparency check works because Weiss Engineering supplies audiophiles with the test audio files. The DAC202 is programmed to look for the exact bit pattern delivered in these files only when playback is bit transparent. Running the bit transparency check is quite simple. All that’s required is setting the DAC to a specific sample rate, selecting Run from the Transparency Menu on the LCD, and playing one of the test files from a computer. When playback is bit transparent the DAC202 indicates the bit depth of the given test file either 16 or 24 bits. If something on the computer isn’t configured correctly the DAC202 simply displays the word Fail. I tried to trick the DAC202 into displaying the bit transparent indicator, but I was unsuccessful after many attempts. Weiss Engineering supplies test files in both 16 and 24 bit word lengths at 44.1, 48, 88.2, 96, 176.4, 192 kHz sample rates.

     

    The third feature that formerly put the Alpha DAC over the top is a simple <b>sample rate display</b>. This seemingly mundane feature can actually help indicate software configuration problems on the fly. Displaying the sample rate of the current track is far from a perfect way to indicate bit transparency, but it’s a step in the belt and suspenders direction. This feature is mainly helpful when an audio output device such as the DAC202 is not configured for Exclusive Output Mode in Windows Vista or 7. As I recommended in my <a href="http://www.computeraudiophile.com/content/Windows-7-Audio-J-River-Media-Center-14-Configuration">Windows 7 / J River Media Center</a> article, it’s wise to set the default Windows sample rate to something like 24 bit, 48000 Hz (Studio Quality). This default format is only used in Shared Output Mode as opposed to Exclusive Output Mode. Shared Output Mode equals compromised sound quality for audiophiles. Thus, when there is an output mode software misconfiguration the Weiss DAC202 clearly indicates 48kHz on the front LCD display no matter what sample rate is actually being played. Since there is virtually no content available at 24/48kHz this is a nice indication that something is wrong.

     

    In high end audio master clocking has traditionally been reserved for the extremely exclusive components from companies like <i>d</i>CS and Esoteric. Now that computer based audio continues to gain in popularity more audiophiles are able to experience and afford a properly master clocked system via asynchronous interfaces on D to A converters. The Weiss DAC202 FireWire interface, when used in conjunction with the internal DAC202 word clock, operates asynchronously. This means the DAC202 is the master clock when playing files from a computer. Currently asynchronous interfaces are all the rage and rightly so. <b>Asynchronous transfer mode</b> can reduce timing inaccuracies by a factor of 100 in well designed DACs. The sonic benefits of certain asynchronous interfaces are well documented by listeners the world over. These positive listening experiences are also backed by solid engineering principals. In the simplest terms timing is critical to the reproduction of recorded sound involving digital to analog conversion. More accurate timing can produce more accurate sound. As of this writing all DACs using FireWire interfaces require third party software to function. The Weiss DAC202 uses a Dice FireWire chip from <a href="http://www.tcelectronic.com/">TC Electronic</a>. Weiss Engineering supplies the Dice software on a CD with the DAC202 and offers the newest versions of the Dice software via its website (password required). Installation of this software is simple frequently requiring a couple clicks and a restart. This software is completely independent of all playback applications like iTunes and J River Media Center, and doesn’t require user intervention after installation. It’s also very important to note that not all devices with FireWire interfaces operate asynchronously like the Weiss DAC202.

     

    In addition to using the DAC202 via asynchronous FireWire in master clock mode it’s possible to use the DAC202 as the <b>master clock</b> with high quality audio cards such as the Lynx AES16, RME HDSPe AES, and Merging Mykerinos. Many engineers that I’ve talked to about word clocking suggest the master clock should remain as close to the DAC as possible. Yet others are adamant about externally clocking all digital devices with a separate word clock. The DAC202 can accommodate either configuration as it offers word clock input and output. When using the word clock output the DAC202 is the master clock and sends a word clock signal to the audio card. These “slaved" audio cards are simply configured to acquire clocking information from an external source instead of using an internal clock. This method keeps the word clock as close to the DAC as possible in an asynchronous-like fashion. Listening through the Weiss DAC202 for hundreds of hours I determined this configuration sounded nearly as good as using the FireWire interface. More on that later. Like all good DAC designs the Weiss DAC202’s audio interfaces are all galvanically isolated. The BNC word clock input is not galvanically isolated.

     

    Two <b>additional differences</b> between the Minerva and the DAC202 are the newly designed analog output stages and newly designed D to A converter. Peaking inside the DAC202 one can see the nicely segregated main analog output stage. The DAC202 offers separate output stages for the main and headphone outputs. Weiss elected to use very good operational amplifiers (opamps) with a high slew rate, and a low impedance topology. According to Daniel this makes the DAC202 even more impervious to cabling and impedance mismatches between DAC and amplifier. The new redesigned D to A converter uses two converters per channel as well as separate converters for the main and headphone outputs.

     

    <b>Using The Weiss Engineering DAC202</b>

     

    There are a number of <b>DAC202 options</b> available via the front LCD display. The DAC202 User Manual is very thorough and offers a detailed technical description of each of the following options. Here is a list of the options in order and some of my notes that correspond to each option.

     

    <b>Main Screen</b>

    <ul>

    <li>Volume: -60 db to 0 db

    Full or half db steps depending on attenuation level. Matching my MC275 input voltage allowed me to listen at or near 0 db.</li>

    <li>Input Source: FireWire, AES (XLR), SPDIF (RCA), SPDIF (TOS)

    Changing the digital source is easily accomplished via the discrete remote commands, and is available via the front panel. This is done right on the main screen without any menu navigation. Software switching of the input source is not available.</li>

    <li>Sample Rate Indicator: 44.1, 48, 88.2, 96, 176.4, 192 kHz

    The sample rate cannot be changed as this is simply an indicator of the current sample rate.</li>

     

    <b>Options Menu</b>

    <li>Abs. Phase: + or -</li>

    <li>Upsample Filt.: A or B</li>

    <li>Sync Source: XLR, RCA, Toslink, WC BNC, 1394 Bus, Internal

    When using the FireWire input I use the Internal word clock exclusively. The 1394 Bus option is only used when multiple DAC202s are connected to the same computer via FireWire. One DAC would be set to Internal and the other would be slaved by setting its sync source to 1394 Bus. Using Lynx AES16 and AES16e audio cards I used both the Internal and WC BNC sync sources. Using the Lynx to send clock to the DAC202 (WC BNC) is not recommended when other options are available. The reverse, sending clock to the Lynx from the DAC is very good sounding. I also set the sync source to XLR but the auto sample rate adjustments by the DAC202 necessitate a one to two second mute while the DAC changes rates. Missing the first couple second of a track can get annoying.

    <li>Sync Rate: 44.1, 48, 88.2, 96, 176.4, 192 kHz

    This option switches the sample rate of the DAC. Manually navigating the menu is the slowest way to accomplish these changes when not running in an auto sample rate switching mode. The simplest method of changing the sample rate is via the Weiss software interface. Simply click the drop-down menu and select the desired rate. The software interface requires a FireWire connection operate although the FireWire interface doesn’t have to be used for audio. During my listening sessions with the Lynx cards running into the DAC202 via AES I always used the Weiss software interface to change the sample rate. It really made no sense to have an XLR connection if a FireWire connection is already present, but this shows the ease of which the software interface works.</li>

    <li>LCD Bright: 0-30 (15)

    I used the 15 setting as it was just bright enough to read in my rather dark listening room. This setting is only active while the LCD is in use for menu navigation or when a setting on the panel (Volume, Sample Rate) is changed. The LCD switches to the LCD Dim Level after around ten seconds.</li>

    <li>LCD Dim Lev.: 0-15 (0)

    I used this setting at 0 as I had no need to continually read the display. During settings changes the LCD illuminates so there is no need, other than aesthetic, to keep the Dim Level above 0.</li>

    <li>Dual WIre: Enabled or Disabled

    Not used for this review. The DAC202 handles all sample rates via single wire.</li>

    <li>DW WCLK: Halfrate or Audiorate

    Set to Audiorate during this review.</li>

    <li>Insert Mode: Disabled, ret. XLR, ret. RCA, ret. TOS

    This is a anti-audiophile option more likely to be used by professionals. It enabled the insertion of external devices like equalizers between the source and the DAC.</li>

    <li>Main Out Att.: Engaged or Bypassed

    I used the Engaged setting exclusively as I had no need to use a preamp between the DAC202 and amp. When set to bypassed the main volume attenuation does not work.</li>

    <li>XLR Out Lev.: 1.06, 2.12, 4.15, 8.15

    This is the very nice coarse analog setting for the main output. As I stated earlier the MC275 sensitivity is 2.5v so I set this level to 2.12.</li>

    <li>Phones Lev.: 0.2, 0.9, 5.2

    This is the coarse analog setting for the headphone output. The default is 0.2v. I used Sennheiser HD600 headphones during the review. these headphones required the 2.7v setting for comfortable listening levels while keeping full use of the fine digital volume control.</li>

    <li>Transparency: Run or Stop

    This is where the built-in transparency check is run. Selecting the Run setting and playing a Weiss supplied file is all that’s required. It’s very easy to use, but was not extremely intuitive. I did have to read the manual.</li>

     

    <b>System Info</b>

    <li>Firmware ver: 1.0.0.3</li>

    <li>SDK Version: 3.5.3.8786</li>

    <li>Model DAC_202 (0x7)</li>

    <li>Weiss OUID: 23</li>

    </ul>

     

    <b>Music Servers, Storage, And Source Material</b>

     

    During the review period I used three main music servers and three types of storage. Two Windows 7 machines, one Mac OS X computer, a NAS drive, external bus powered drive, and internal SSD.

    <ol>

    <li>The Computer Audiophile Pocket Server (C.A.P.S.) <a href="http://www.computeraudiophile.com/content/Computer-Audiophile-Pocket-Server-CAPS">[Details]</a> Since the C.A.P.S. machine does not have a FireWire port I purchased an internal PCI FireWire card to connect to the DAC202. Some CA readers have reported issues using certain FireWire chipsets. The card I purchased uses the VIA 6307 PCI to FireWire IEEE1394a controller chip and worked flawless. There was no software installation required under Windows 7. The card is manufactured by SYBA, model number SD-VIA-FW1E1H. The best part about this card is the $7.99 price from NewEgg <a href="http://www.newegg.com/Product/Product.aspx?Item=N82E16815124034">[Link]</a>. This card offers a single external FireWire 400 port and a single internal FireWire 400 header to connect a FireWire port to the computer case if necessary.

    <li>MacBook Pro 13" [Model Identifier: MacBookPro5,5] running Mac OS X 10.6.3 and 10.6.4 Snow Leopard. An Intel Core 2 Duo processor running at 2.26 GHz and 4 GB of RAM. The internal Solid State Drive (SSD) is a 120 GB OCZ Vertex Turbo (MLC). Amarra version 2.0, iTunes 9.2 (61), and Songbird 1.7.3 Build 1700. To connect the DAC202 I started by using a noname FireWire 800 to 400 converter and a Monster Cable FireWire 400 to 400 (6 pin to 6 pin) cable. Most of my listening through this MacBook was done on battery power only and wired Ethernet or no network connection at all.</li>

    <li>MacBook Pro 13" [Model Identifier: MacBookPro5,5] running Windows 7 Ultimate 32 Bit. An Intel Core 2 Duo processor running at 2.26 GHz and 4 GB of RAM. The internal Solid State Drive (SSD) is a 120 GB OCZ Vertex Turbo (MLC). J River Media Center v14 and v15. Started using a noname FireWire 800 to 400 converter. After a few issues where the DAC202 disappeared from the computer I switched to a single FireWire 800 to 400 cable. This did not resolve the issue 100% but I am currently unable to reproduce the issue at the time of this writing. The issue was only present under Windows 7. According the Weiss FireWire software the following informatioin is available about the drivers and FireWire chipset in my MacBook Pro. Drivers - Microsoft 1394ohci.sys [6.1.7600.16385], Microsoft ohci1394.sys [6.1.7600.16385] (legacy), Microsoft 1394bus.sys [6.1.7600.16385] (legacy). I tried all three even though they look awfully similar. OHCI 1394 Host Controller - Vendor : (11C1) LSI (Agere, Lucent), Chipset: (5901) FW643, Revision: 07, Status : Active, Details: Subsysten VendorId: 11c1, Subsystem DeviceId: 5900, Max # isoch Rx contexts: 8, Max # isoch Tx contexts: 8, Max 1394 Speed Capability: S800, Support: Compatible, no known issues. Most of my listening through this MacBook was done on battery power only and wired Ethernet or no network connection at all.</li>

    <li>I used three different NAS drives during this review. A. Thecus N5200B Pro, B. QNAP TS-559 Turbo NAS Pro, and C. Synology DS710+.</li>

    <li>The external drive used was an Oyen Digital MiniPro 750GB 5400RPM External 2.5-in FireWire 800/400, USB Portable Hard Drive <a href="http://oyendigital.com/hard-drives/store/CB2-54-750-M.html">[Link]</a>. This drive is powered from the USB or FireWire bus and uses the Oxford 934 chipset (OXUF934SSA). A switching power supply is available but not recommended for high end audio applications. I had success using the daisy chain capability of FireWire when connecting this FireWire 800 drive directly to the MacBook Pro and connecting the DAC202 via FireWire 400 to 800 cable to the drive. Note the faster FireWire devices should be connected closer to the computer when daisy chaining with devices of differing speeds.</li>

    </ol>

     

    Much of the source material used during this review was either 16/44.1 kHz or 24/96 kHz, with a small dusting of 24/176.4 kHz HRx material. 90% of the files were encoded in FLAC and copied to memory before playback in J River Media Center. The main Windows audio output method used was WASAPI. ASIO and Kernel Streaming both worked just as good as WASAPI through JRMC v15. I was unable to discern a sonic difference during the review period between either of the three output methods.

     

    During the course of the review I up the firmware and Weiss software once. The process was simple. A rare software bug that only manifest itself under a twisted concoction of configuration changes was fixed and there was no change in sound quality.

     

     

    <a href="http://images.computeraudiophile.com/graphics/2010/0617/weiss001.PNG" class="thickbox" rel="dac202"><img src="http://images.computeraudiophile.com/graphics/2010/0617/weiss001-small.png"></a>   <a href="http://images.computeraudiophile.com/graphics/2010/0617/weiss002.PNG" class="thickbox" rel="dac202"><img src="http://images.computeraudiophile.com/graphics/2010/0617/weiss002-small.png"></a>   <a href="http://images.computeraudiophile.com/graphics/2010/0617/weiss003a.PNG" class="thickbox" rel="dac202"><img src="http://images.computeraudiophile.com/graphics/2010/0617/weiss003a-small.png"></a>   <a href="http://images.computeraudiophile.com/graphics/2010/0617/weiss004a.PNG" class="thickbox" rel="dac202"><img src="http://images.computeraudiophile.com/graphics/2010/0617/weiss004a-small.png"></a>   <a href="http://images.computeraudiophile.com/graphics/2010/0617/weiss005.PNG" class="thickbox" rel="dac202"><img src="http://images.computeraudiophile.com/graphics/2010/0617/weiss005-small.png"></a>   <a href="http://images.computeraudiophile.com/graphics/2010/0617/weiss006.PNG" class="thickbox" rel="dac202"><img src="http://images.computeraudiophile.com/graphics/2010/0617/weiss006-small.png"></a>   <a href="http://images.computeraudiophile.com/graphics/2010/0617/weiss003b.PNG" class="thickbox" rel="dac202"><img src="http://images.computeraudiophile.com/graphics/2010/0617/weiss003b-small.png"></a>   <a href="http://images.computeraudiophile.com/graphics/2010/0617/weiss004b.PNG" class="thickbox" rel="dac202"><img src="http://images.computeraudiophile.com/graphics/2010/0617/weiss004b-small.png"></a>

     

     

     

    <b>Weiss DAC202 Sound Quality</b>

     

    During the several weeks I spent listening to the DAC202 there was nothing more I wanted to talk about then its sound quality. I enjoyed being contacted by Weiss dealers, who had yet to receive their DAC202s, to discuss how good this DAC sounds. The DAC202 actually takes the cake for the component I’ve spent the most time listening through. Even after removing my reviewer’s hat for the evening I often felt compelled to listen to more music. I’ve had other components in here that enabled me to listen to a lot of music, but nothing like the DAC202 that compelled me to listen. Listening critically to more music that sounds fabulous elevates the whole experience to another level. It seems like every time I listened it was critical and in a good way. I was sucked into the music, yet I could explain the detail that I was hearing in every instrument. At no time did I listen to the DAC202 and get sidetracked by life’s daily distractions. After listening to several other components over the years I clearly remember not being able to answer sound quality questions until I sat down with a notebook and scratched a few words on paper. The music definitely leaves an imprint on one’s mind when listening through the DAC202.

     

    The two sonic characteristics that won’t leave my mind for a long time are full, vibrant, and cohesive soundstage, and fabulous, full, nonbloated, midrange that’s to die for. The aforementioned adjectives are what the music sounds through the DAC202, not what the DAC202 sounds like. It just doesn’t seem right to discuss the sound of a component when the music is all I could thinnk about. I won’t even suggest the DAC202 is without a sonic signature. In fact all of this describes its sonic signature. It’s just that the music is what sticks in my head. The DAC202 has a way of presenting the music instead of presenting itself. Listening to the 24/96 download of <a href="https://www.hdtracks.com/index.php?file=catalogdetail&valbum_code=HD00731454330428">Ella and Louis</a> over and over again caused me to chuckle a bit in my listening chair. When something sounds good it’s hard not to get giddy. The coherency and illusionary image presented when listening to this album was astounding. Shelby Lynne’s new album <a href="http://www.amazon.com/Tears-Lies-Alibis-Shelby-Lynne/dp/B0039ZF86E/ref=sr_1_1?ie=UTF8&s=music&qid=1276821794&sr=1-1">Tears, Lies, and Alibis</a>, mixed by Al Schmitt at Capitol Studios in Hollywood and mastered by Doug Sax & Sonny Nam at the Mastering Lab in Ojai, California, sounded superb through the DAC202. I felt as though I could hear everything. Like nothing was really between me and the music. The midrange detail that came through reminded me of the Shelby Lynne concert I attended May 2nd, 2010 at the small Dakota Bar and Grill in Minneapolis. In no way was my system producing sound as real as the concert, but the thought to compare live v. recorded Shelby Lynne entered my mind several times.

     

    Since the DAC202 supports all reasonable sample rates including 176.4 and 192 I could listen to my Reference Recordings HRx material in its native resolution. My go-to album Crown Imperial by the Dallas Wind Symphony (<a href="http://www.referencerecordings.com/HRxORDER.asp">HR-112</a>) revealed a bit more about the Weiss DAC202. The higher frequencies are smooth yet accurate as far as I can tell. This smoothness is possibly rounding the leading edge of transients. I say possibly because my McIntosh MC275 tube amplifier isn’t known for tack sharp transients and ear piercing pings. The bottom and mid to lower frequencies appeared to be right-on. I didn’t notice any annoying bass exaggeration or emphasis. I’m guessing the low jitter FireWire interface has a lot to do with this low end clarity and appropriate punch. Listening to Marcus Miller’s Silver Rain album, specifically track one, through the Weiss DAC202 is enough to solidify anyone’s opinion that this DAC has great control in the bottom end.

     

    The best sounding interface to listen through was FireWire. Using a Lynx AES16 card into the DAC202’s AES/EBU input and slaved to the DAC202’s word clock was a close second place. The externally clocked Lynx configuration just wasn’t as cohesive as listening through the FireWire interface. The Lynx was a bit sloppy sounding. Plus, the FireWire interface is incredibly convenient compared to a Lynx card and only requires a computer with a FireWire port not a PCI slot.

     

    The fourth factor I considered back in December 2008 that sunk the Minerva in my mythical rankings was its soundstage. In the Alpha DAC review I said, <i>“In my opinion the major sonic difference between the two [Alpha and Minerva] is soundstage...The Minerva has a much more focused soundstage that may be narrow to some listeners. On the other hand this focussed and tight soundstage is exactly what some listeners are seeking. In a way the Minerva is like plugging into the soundboard to make a live recording and the Alpha DAC is like placing microphones elsewhere in the venue. “</i> Comparing the soundstage of the Alpha to that of the DAC202 was almost painful for me. The Alpha has been my old faithful for a couple years. It’s always been an overachiever. After listening to the DAC202 for long enough it was time to face the music. The DAC202 has a much more cohesive soundstage than the Alpha and has lost any overly narrow characteristics present in the Minerva. Comparing recording after recording revealed the same results. The appropriately sized and high cohesivity of the DAC202’s soundstage and its superior imaging schooled the Alpha DAC.

     

    <b>Are We There Yet?</b>

     

    <a href="http://images.computeraudiophile.com/ca/cash-logo-black.png" class="thickbox" rel="cash"><img src="http://images.computeraudiophile.com/ca/cash-logo-black-thumb.jpg" style="padding: 2pt 5pt 2pt 2pt;" align="left" alt="CASH-List"></a>Back to the hovering question. Are we there yet? The combination of a good Windows 7 or Mac server and the Weiss Engineering DAC202 is enough to transport anyone into the world of high end computer audio. The DAC202’s support of all reasonable sample rates via a ubiquitous and low jitter asynchronous FireWire interface, impeccably implemented coarse analog / fine digital volume control, built-in transparency checking, sample rate display, and sound quality to plan this year’s bonus around make it the vehicle that gets anyone “There" and well beyond the capabilities of traditional transports. The DAC202 not only offers all the features required for the foreseeable future it’s the sound quality valedictorian of its class and the latest entrant to the <a href="http://www.computeraudiophile.com/content/Computer-Audiophile-Suggested-Hardware-List">C.A.S.H. List</a>. Now that we’ve answered the “are we there yet" question it’s time to ask, What are you waiting for?

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

    Product Information

    <ul>

    <li>Price - $6,670</li>

    <li>DAC202 Product Page - <a href="http://www.weiss-highend.ch/dac202/index.html">Link</a></li>

    <li>DAC202 Product Brochure - <a href="http://files.computeraudiophile.com/2010/0617/dac202-brochure.pdf">Link</a></li>

    <li>DAC202 Manual - <a href="http://files.computeraudiophile.com/2010/0617/dac202-manual.pdf">Link</a></li>

    </ul>

     

     

    Associated Equipment:

     

    <a href="http://files.computeraudiophile.com/2010/0418/Brochure_Fidelio.pdf">Verity Audio Fidelio loudspeakers</a>, <a href="http://www.mcintoshlabs.com/products/mcintosh-mc275-vacuum-tube-power-amplifier.asp">McIntosh MC275 amplification</a>, <a href="http://www.richardgrayspowercompany.com/products.aspx?type=accessories">Richard Gray's Power Company High Tension Wires</a>, <a href="http://www.berkeleyaudiodesign.com/">Berkeley Audio Design Alpha DAC</a>, <a href="http://www.usbdacs.com/Products/Products.html">Wavelength Audio Proton</a>, <a href="http://www.ayre.com/products_detail.cfm?productid=12">Ayre AX-7e Integrated Amp</a>, <a href="http://www.computeraudiophile.com/content/Computer-Audiophile-Pocket-Server-CAPS">C.A.P.S. server</a>, <a href="http://www.belcantodesign.com/Product_USBlink.html">Bel Canto USB Link</a>, <a href="http://www.halidedesign.com/bridge/">Halide Design Bridge</a>, <a href="http://www.dcsltd.co.uk/product/debussy-dac"><i>d</i>CS Debussy DAC</a>, <a href="http://www.dcsltd.co.uk/product/puccini-u-clock"><i>d</i>CS Puccini U-Clock</a>, <a href="http://www.kimber.com/products/interconnects/digital/usb/bbus/cu/">Kimber USB Cu</a>, <a href="http://www.kimber.com/products/interconnects/digital/usb/bbus/ag/">Kimber USB Ag</a>, <a href="http://www.benchmarkmedia.com/system1/digital-analog-converter/dac1-pre">Benchmark DAC1 PRE</a>, <a href="http://www.kimber.com/products/interconnects/analog/select/singleended/ks1011/">Kimber Select KS1011 Analog Cables</a>, <a href="http://www.kimber.com/products/interconnects/digital/select/ks2020/">Kimber Select KS2020 Digital Cable</a>, <a href="http://www.kimber.com/products/loudspeakercables/monocle/x/">Kimber Monocle X Loudspeaker Cable</a>, <a href="http://usa.asus.com/product.aspx?P_ID=SPZfqXDJvadmFPoh&templete=2">ASUS Xonar HDAV 1.3 Slim</a>, <a href="http://www.apple.com/ipad/">Apple iPad</a>, <a href="http://www.amarraaudio.com/">Sonic Studio's Amarra</a>, <a href="http://www.m2tech.biz/products.html">M2Tech hiFace</a>, <a href="http://www.weiss-highend.ch/dac202/index.html">Weiss Engineering DAC202</a>, <a href="http://www.lynxstudio.com/product_detail.asp?i=13">Lynx Studio AES16 Digital I/O Card</a>.

     

     

     

     

     

     

     

     




    User Feedback

    Recommended Comments



    Hi Chris, i think your review is very good. It is obvious to me that it has taken a great deal of effort to write it.<br />

    <br />

    Was there no negative aspects of the sound in your opinion?<br />

    In my experience, a dac is usually a compromise, and is not normally best at everything.<br />

    <br />

    And how was this dac in comparison to the dcs gear?<br />

    <br />

    Thanks:)

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    Dear fand1<br />

    I am glad you liked Chris's review. I did not. I am sure the 202 is an excellent product. I have no axe to grind. I would be delighted to have a 202 in my system.<br />

    Regards<br />

    Andrew

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    <em>"I'm responding to the comment that for 1/4 the price you can get 3/4 the performance. I claim that you can get 99% of the performance for 1/4 the price. I have no idea how the poster intended to quantify 3/4, so I gave one possibility for my 99% claim: 99 out of 100 people can't hear the difference"</em><br />

    <br />

    I think I made that comment...<br />

    <br />

    The figures of 3/4 of the performance as pretty arbitrary figures. There is just no objective way to apply numbers to the performance of a piece of audio equipment so they can be compared in this way - however the 3/4:1/4 ratio is something thats often commented on. To (significantly) improve on a good £200 CD player - there's no point spending £500, you need to spend £800. Equally to improve on a £1,500 DAC that means spending £6,000 or so. Not that there aren't some products that are absolute bargains!<br />

    <br />

    As for if £6,000 is expensive - well you can buy a small car for that yes - but then you can equally spend £60,000 on a car which isn't much bigger and for day to day use won't get you "there" any quicker. <br />

    <br />

    Eloise

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    Chris,<br />

    <br />

    Sorry for being late to the party... Have been at NAMM showing my new guitar amps. Great show... utterly crazy music.<br />

    <br />

    Anyways... I did a lot of development with Oxford Semiconductor back in 2004 with their OXFW970 Firewire controller and then the 971 which is the basis for the DICE II as the Oxford stuff was sold to TC when Oxford wanted to work primarily on their USB/Firewire bridge products.<br />

    <br />

    In looking at the DICE data sheets I really cannot see how this can possibly accomplish an Asynchronous link. First how is feeding a word clock back to the computer going to accomplish this. This is only a reference the DICE chip locks the output I2S signal on the incoming stream which means... even if you do the word clock feedback that the resulting I2S clock going to the dac will not be exactly the same as the word clock output. Second as I can tell from the work I have done with sound groups for both MAC and PC that this is a generalized concept and not a finite one.<br />

    <br />

    Does the Weiss have fixed Master Clock oscillators?<br />

    <br />

    Really the only true way to accomplish an Asynchronous method for a dac is to have fixed oscillators at the dac chip and use these oscillators to derive the I2S feed going to the dac chip. Therefore the only real protocol between the Computer and the DAC would have to have some inherent feedback or flow control to make for an asynchronous link.<br />

    <br />

    Please explain???<br />

    <br />

    Thanks<br />

    Gordon

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    Gordon: I cannot help thinking that at best it is inappropriate to question a reviewer about the technical possibilities of a product. At worst it is disingenuous-verging on a shill for you or your products. If I were Chris, I'd have pulled that comment and strongly warned you...

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    Obviously 4est, you need to read Chris' review again. Chris mentioned that the Weiss 202 used an asynch interface with the computer. Gordon asked how this was accomplished.<br />

    <br />

    Why don't you answer this question for us?<br />

    <br />

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    Wow,<br />

    <br />

    I am more than interested in the issue this question has arisen.<br />

    <br />

    I am right now testing the weiss int202 on my dCS rig, and there is no benefit at all against my belcanto usb link.<br />

    <br />

    Could that be an explanation ? (I am desperate to find one).<br />

    <br />

    Elp

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    You missed my point. I do not feel it is appropriate for Gordon to draw attention to himself and draw speculation towards his competitor. Chris is not an engineer, but a reviewer.<br />

    <br />

    It smells funny to me. I do not know the answer, but question the reason why it is asked in this fashion. It seems self promotional. He may have asked how this was accomplished, but only after touting his own expertise.

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    "If I were Chris, I'd have pulled that comment and strongly warned you..."<br />

    <br />

    <br />

    <br />

    Gordon made not one but two very cogent, and appropriate comments about specifics in Chris's review, although admittedly Chris might not have the answer at hand (to Gordon's questions), nor should he be expected to.<br />

    <br />

    1) He pointed out that Weiss' Firewire DAC might not be operating asynchronously (per the definition normally used by posters here on CA). This is important due to the fact that Firewire is not always Asynchronous, and, in fact, requires effort by the manufacturer to implement it thusly.<br />

    <br />

    2) He also pointed out (or rather, reminded all of us) that Asynchronous transmission is not the best manner in which to describe the design characteristic that is normally attributed to Async - i.e. use of fixed oscillators by/in the DAC (as the master clock).<br />

    <br />

    In other words, a DAC might be using an Async interface, but NOT be using fixed oscillators as the master clock, and thereby not be benefiting from the gains many here associate (incorrectly) with Async interfaces.<br />

    <br />

    Clay<br />

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    Jeez- Come on, Weiss doesn't need me to promote his products, nor defend them. It just seems a bit bush league to have done it in this fashion. Rightly or wrongly, there was a less self promotional way to ask this question.<br />

    <br />

    If I am the only one whom feels this is a bit "off", then please forgive me.

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    I'm not sure how relevant this is, but my Weiss AFI1 uses the 'DICE' chip, and not the 'DICE II' chip. I suspect the DAC202 uses the former.<br />

    <br />

    Gordan, do your comments apply to the 'DICE' chip also?<br />

    <br />

    Mani.

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    has brought up some relevant points here, and I for one would like to know the exact answer. Does the Weiss 202 use fixed frequency oscillators for the firewire input, or is the clock derived from the PLL circuit? In other words, is the Firewire interface used in a truly asyncronous fashion (as understood by those here to mean fixed frequency oscillators, controlling both the flow rate of data from the computer and the DAC chips)?<br />

    On the other hand, Gordon's post does seem a little self serving (even more so if he is incorrect) and it would probably have been better for him to contact Chris, and/or Daniel Weiss through private e-mail to discuss whether there is an error in the review, and then allow Chris to make revisions if necessary.<br />

    Ultimately a Stereophile review of the DAC 202, with a measured jitter spectrum would likely be the best answer, as then the measured jitter performance could be compared directly with that of the Ayre QB-9 (as also measured by John Atkinson, Stereophile).

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    <br />

    This from the DAC202 manual, explaining how the DAC202 suppresses jitter.<br />

    <br />

    <br />

    "... the D/A converter has to run synchronous to the incoming digital audio signal and thus the frequency of the internal sampling clock generator has to be controlled so that it runs at the same sampling speed as the source (e.g. CD transport). This controlling is done by a Phase Locked Loop (PLL), which is a control system with error feedback. Of course the PLL has to be able to follow the long term fluctuations of the source, e.g. the sampling rate of the source will alter slightly over time or over temperature, it will not be a constant 44.1kHz in the case of a CD. But the PLL should not follow the short-term fluctuations (jitter). Think of the PLL as being like a very slow-reacting flywheel.<br />

    <br />

    In the DAC202 we employ a two-stage PLL circuitry, which very effectively suppresses jitter."<br />

    <br />

    Doesn't seem like either Asynchronous transmission OR fixed rate oscillators are in use to me.<br />

    <br />

    Further in the section of the manual referring to Sync Sources are details on using the DAC's Clock as Sync SOurce (i.e. Master)<br />

    <br />

    "- Internal: The DAC202 generates the sampling rate clock internally. Note that in this mode the source has to be synchronized to the internally generated sync. With Firewire as input source this is done automatically via Firewire. With the other inputs the source, e.g. a CD transport has to by synchronized via e.g. the sync out<br />

    BNC connector at the back of the DAC202."<br />

    <br />

    Kudos to Daniel Weiss for putting together a great manual, complete with details on the theory (as seen by Weiss).<br />

    <br />

    clay<br />

    <br />

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    Hi guys - I don't want to hinder any discussion but I do want readers to carefully think about posting armchair engineer "answers" to this developing async question. This statement is not directed at anyone in particular.<br />

    <br />

    I asked this exact async question before publishing the review to exercise due diligence. I am now working hard to find a definitive answer for the CA readers.<br />

    <br />

    Please be patient.

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    >> $500 and Async USB. I just know someone can produce this stuff for this dollar amount. <<<br />

    <br />

    Yup.<br />

    <br />

    Just make it in China and use only op-amps instead of discrete circuitry.<br />

    <br />

    Those things aren't good or bad except to an individual user. But that's how you make things for $500. Heck, Gordon's Proton is Async USB and it's only $900. It's made in the USA and uses only op-amps. Starting to see a pattern? It's called "there's no such thing as a free lunch".<br />

    <br />

    Clearly there is a demand for less expensive DAC's. I don't think the DAC Magic is what most people are looking for. For many people the Arcam will fill the bill quite nicely. But don't pretend that you are getting a $2500 DAC for $500.

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    Chris,<br />

    I was in the middle of editing my post, and was unable to update it due to your reply. At risk of not heeding your comments, I am posting my updated comments below<br />

    <br />

    <br />

    "- Internal: The DAC202 generates the sampling rate clock internally. Note that in this mode the source has to be synchronized to the internally generated sync. With Firewire as input source this is done automatically via Firewire. With the other inputs the source, e.g. a CD transport has to by synchronized via e.g. the sync out BNC connector at the back of the DAC202."<br />

    <br />

    There is definitely room for interpretation here.<br />

    <br />

    The question becomes - what is meant by "done automatically by Firewire"?<br />

    <br />

    Does this mean that Firewire (in Internal mode) obviates the need for synchronization (as described above), or does it mean that Firewire drivers provided by Weiss synchronize the clocks in a manner similar to use of an external clock? <br />

    <br />

    Presumably it doesn't even matter so long as the DAC's clock is being used as Master, and is a fixed oscillator.<br />

    <br />

    As Chris says, probably only Daniel can provide the answer.<br />

    <br />

    clay<br />

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    Just a thought r.e. your question on feeding your DCS stack... <br />

    Do you convert PCM to DSD before DA or use other (a-sync) SRC? If so... you might be pretty much fixed (and async) .. :-)<br />

    <br />

    The INT202 will allow the higher samplerates over the Belcanto..<br />

    Just my 2 cts<br />

    <br />

    Hans<br />

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    Just a couple of comments from the eye surgeon who knows just enough about electrical engineering to frustrate the whole list with his questions.<br />

    1. I enjoy manufacturer's comments, and enjoyed reading those by Gordon Rankin and Charlie Hansen. We know who they are, let them talk.<br />

    2. I do not want their comments "suppressed" by direct e-mails to Chris. I want to know what they think, at least as much as I do any for the other so called "experts" on the list. If they are wrong, tell them so. If we can't do that what the heck is the net worth anyway?<br />

    3. Charlie, I know there is no free lunch, but I'll say it since you can't- the QB-9 is one fancy Ritz dinner for the price of a diner sandwich compared to the Weiss or Berkeley (that I bought). Yes, the Berkeley is better, but no where near twice as good, for twice the price, plus cost of a lynx card. You two both take some credit for that.<br />

    4. Gordon, any news on the Wavelink 24/192? I can't wait to compare the Berkeley with the Wavelink to the 202 or DCS stuff. Is the Apple software glitch fixed yet? <br />

    <br />

    I gave you the introduction- feel free to comment on your product as a response to my question, hopefully without the fear of an accusation of manufacturer bias....<br />

    <br />

    :^)<br />

    <br />

    <br />

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    Hi rlodad - If you want to discuss products unrelated to the subject of this review I encourage you to start another forum thread. That way others will certainly find it when browsing the forum for such information. The answers to your questions should see the light of day and not be buried 100 comments down in a review about the Weiss DAC202.<br />

    <br />

    Thanks for your understanding :~)

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    @Charles Hansen...<br />

    <br />

    At the risk of sounding like I'm biting the head of another manufacturer commenting on a competitors products, do you know for a fact that the Arcam R-DAC is made in China (or other Far East country) as generally Arcams products are made in the UK. They did go through a period where their AVR line was made in China but the recent (AVR600 and 500) have returned to UK manufacture. This includes (afaik) the Solo range which superficially the R-DAC is part of. <br />

    <br />

    Eloise

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    <br />

    eloise, <br />

    your question is certainly a fair one, but I didn't get the impression Charles was referring specifically to the Arcam. I took his response as general in nature. I do agree with his point (perhaps mostly implicit) that just becuase a DAC might be Async doesn't mean it will sound as good as better engineered DACs, whether Async or not. Cheaper DACs have to cut corners somewhere. Providing a low-quality Async DAC becuase it's a hot market for such will disappoint many and drag down the appeal of Async USB - neither of which is good for anyone. Mind you, I do NOT think anything Arcam does will be low quality.<br />

    <br />

    I AM interested in Arcam's products generally, esp. use of trickle down from dCS, as my last CD player was the Arcam CD23 with dCS RingDAC.<br />

    <br />

    Do you know if in fact they are licensing dCS Async USB?<br />

    <br />

    cheers,<br />

    clay<br />

    <br />

    <br />

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    "2. I do not want their comments "suppressed" by direct e-mails to Chris. I want to know what they think, at least as much as I do any for the other so called "experts" on the list. If they are wrong, tell them so. If we can't do that what the heck is the net worth anyway?"<br />

    <br />

    Suppressed, really?? This is quite a cynical comment. My point in suggesting that Gordon contact Chris directly was made in the view that Gordon was not certain exactly what is happening inside the Weiss 202, he was just raising a suspicion. In any case, I would never expect Chris to be one to "suppress" information as long as that information was confirmed to be correct. A manufacturer needs to be held to a high standard when commenting on public forums, especially if commenting about a competitors product, and speculative comments seem a little over the line to me.<br />

    <br />

    Clay: re the sections of the manual that you have refferred to, I find it unclear as to whether the PLL circuit is the clock generator only for the SPDIF inputs, or also for the Firewire input. For the SPDIF inputs a PLL is necessary, so it is understandable that there is one in the 202. In any case, I think we can relax and wait for Chris to get confirmation from Daniel Weiss as to how the clock is generated for the Firewire input.

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    Does quality really have anything to do with the cost of parts? or whether or not opamps are used? How much more can discrete circuits cost? When I see the inside of any of the top rated DACs or high end products I can't help but think the cost to make the boards appears to be minimal compared to the MSRP of any of these products. I'm thinking they spend more per unit on marketing than building the product.<br />

    <br />

    The sound probably has more to do with brilliant engineering. Some designers are more talented than others. And some of the best are more generous than others and their products are more reasonably priced. ie; Metric Halo seems to be a good example of brilliant engineering combined with generosity. You get a lot for the money. And people are raving about the sound of those opamps!

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    The TC Electronic DICE II PLL chip used by the DAC2 and DAC202 is described in US patent 7,495,516 and in the following AES technical paper (which is easier to understand than the patent):<br />

    http://www.tcelectronic.com/Media/frandsen_travis_2006_clean_clocks_tc(1).pdf<br />

    <br />

    The paper clarifies that the DICE II chip is a PLL that performs the same function as any other PLL. It is a specific PLL design, not a scheme for avoiding the PLL.<br />

    <br />

    Any use of a PLL to extract a clock from an incoming Firewire or AES audio stream is completely different from the flow control and fixed master clock used by asynchronous USB DAC’s from Wavelength, Ayre and dCS.<br />

    <br />

    Specifically, the paper states the purpose of the DICE II chip is to synchronize a local clock to the clock of an input stream, such as a Firewire 1394 isosynchronous input stream (see Abstract; sec. 1.1, last paragraph; sec. 2.3). The DICE II chip uses two cascaded PLL’s: (1) a digital PLL with a fixed master clock and numerically-controlled digital frequency divider, followed by (2) an analog PLL with a voltage-controlled oscillator. One of the stated advantages of the DICE II chip is to avoid the need for multiple fixed frequency clock chips (sec. 2.7).<br />

    <br />

    This supports Gordon Rankin’s interpretation that, in Internal Clock mode, the Weiss DAC202 acts like an external master clock that sends a clock to the computer to regulate the timing of the Firewire audio signal, but the DAC202 then treats the incoming Firewire audio no differently than an AES signal. That is, the DAC202 uses the DICE II PLL to extract the clock from the Firewire audio signal the same way it extracts the clock from an AES audio signal.<br />

    <br />

    (This interpretation is further supported by the existence of the Operation Mode / Stability setting in the DAC202 control panel software. This appears to control the parameters of the PLL. It would not be needed if the DAC202 were using a fixed master clock instead of a PLL.)

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    >> I'm curious about the Arcam also. I read somewhere that they license the asynch technology from DCS. Not that the asynch transfer is the whole DAC but it's good to know the transfer won't be the weak link in the product. Anyone know if the DAC will actually do 4X sampling rates. <<<br />

    <br />

    My understanding is that the Arcam uses the TI TAS1020B USB receiver chip. This is only USB 1.1 capable and tops out at 96/24.

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